Archive Magazine CD 1995/Archive Magazine CD 1995.iso/text/magazine/volume_08/issue_12

Text File | 1995-08-01 | 304KB | 6,435 lines

Acorn − The New Generation
8.12
Paul Beverley
8.12
Having sold around 25,000 Risc PC 600s, Acorn has now launched the
follow-up − yes, you’ve guessed it, the ‘Risc PC 700’. Also, there’s the
new ‘A7000’ aimed to bridge the gap between the A4000 and the Risc PC.
8.12
Top-of-the-range improvement
8.12
If you look at the top-of-the-range Risc PC 700, the ACB75, and compare
it with the top-of-the-range Risc PC 600, the ACB45, you will see that
it is good news (for those who haven’t recently bought an ACB45).
Despite the price staying almost the same (£1989 instead of £1996 inc
VAT), as well as getting the ARM710 instead of the 610, the hard drive
size has doubled to 850Mb, the VRAM has doubled to 2Mb (although that is
still the maximum capability) and the sound is now 16­bit. The ROM size
has doubled to 4Mb so that it can contain all the apps (Draw, Paint,
Edit, etc) as well as !Printers, JPEG facilities and Access and TCP/IP
networking software.
8.12
The rest of the range
8.12
If you only want one slice, you can choose the ACB70 at £1599 (inc VAT).
This is the same memory size as the ACB25 (5Mb) but has double the hard
disc size (425Mb).
8.12
Going down the price scale, the next new computer is a new Risc PC 600,
called the ACB60. For £1349 inc VAT, this gives you a computer the
same as the ACB70 except that it has an ARM610 and no VRAM and no
backplane, but it is completely upgradable to the top-of-range and
beyond − all except the Risc PC 600 logo which is not upgradable. Acorn
have no plans to do a “drive­door-trade-in”, sorry!
8.12
Cheaper still...
8.12
We still haven’t finished because Acorn have provided a further range of
ARM7 computers that have an even lower price entry point. The A7000
series is a new small-footprint computer based on the ARM7500 processor,
a composite chip like the ARM250 (as used in the A4000/3020/3010) which
combines the processor core plus VIDC20 plus IOMD in one chip, reducing
the chip count to a very low level and thereby reducing the cost.
8.12
The price starts at £1049 inclusive for the AMC01 − a 2Mb computer with
no hard disc suitable (only) for use as part of a network system − it
has an Ethernet card fitted as standard. And don’t laugh at the fact
that it only has 2Mb RAM. Yes, the ACB15 with 2Mb of RAM was a non-
starter for anything serious but, with so much held in ROM, including
network software and !Printers, you can have a networked, printing ARM7
computer with about 1.2Mb available for applications. (Try THAT on a PC
or a Mac!!!)
8.12
For an extra £50 (£1099) the AMC02 is available with a 425Mb hard drive
but without the Ethernet card. The next model up, the AMC03 at £1199,
has 4Mb of RAM instead of the 2Mb of the AMC02.
8.12
The trade-off with the A7000 is that it doesn’t allow you to add any
video RAM and it doesn’t have the amazing upgradability of the Risc PC
600 and 700 computers. Like the ACB60 and 70, it has one empty 5¼“ bay
but it’s a fixed size box, so you cannot add extra slices for more
space. Also, it has only one expansion card slot and this is an
alternative to, say, putting a CD­ROM in the 5¼” bay. i.e. you cannot
have a populated 5¼“ bay and an expansion card. In terms of memory
upgradability, the 2Mb or 4Mb it comes with as standard is soldered onto
the pcb but it has a single SIMM slot which could have up to a 128Mb
RAM, taking it to a maximum of 132Mb (compared to 258Mb for the 600/700
computers).
8.12
Other add-ons
8.12
If you prefer a 17“ monitor to the 14” AKF60, you can have an AKF85 with
any of these computers for an extra £326. (The AKF85 isn’t listed by
Acorn as an option with the A7000s because it has no video RAM and may
not warrant using a 17“ monitor, but I’m sure most dealers would allow
you to mix and match if you wanted to do so.)
8.12
For CD-ROM, Acorn provide an Atapi dual speed drive which, if bought
with the computer, costs just £130 inclusive.
8.12
Even better prices?!
8.12
As explained below, Acorn have brought in a direct-selling policy for
education which means that all these computers are available to schools
and colleges at even lower prices. The following table gives the RRP and
the REP (Recommended Education Price) rounded to the nearest pound.
8.12
  RRP  REP
8.12
ACB75  £1989  £1761
8.12
ACB70  £1599  £1409
8.12
ACB60  £1349  £1174
8.12
AMC01  £1049  £880
8.12
AMC02  £1099  £939
8.12
AMC03  £1199  £1028
8.12
Acorn’s new education policy
8.12
For years now, Acorn education dealers have been waging war − on each
other! Let me explain... An Acorn dealer goes into his local school and
convinces them that Acorn provide the best option, whether it’s for
curriculum software or networking or one-per-child computing. The school
decides what it wants and then, because finance is tight these days,
they shop around to find which dealer will give the best quote for the
system(s) they want.
8.12
Often, the local dealer loses out to a box-shifting company that can
afford to sell for 2 or 3% margin − a crazy situation because it
mitigates against the well-qualified, keen, local dealers for a small
overall saving for the schools.
8.12
Acorn’s radical solution is to sell direct to schools − well, sort of!
They have appointed about 25 Acorn Agents − mostly ex-Education Dealers
who are each given a “slice” of the country including, hopefully, some
reasonably Acorn-friendly areas as well as some Acorn-opportunity areas
where there is great potential for winning schools (back) to Acorn. The
Agents make the sales (with help from the big boys at Acorn for big
contracts) and Acorn supply the computers direct to the schools at the
prices mentioned above (actually, ‘REP’ is a misnomer as they are not
“recommended”, but fixed prices). The Agents then get a commission for
every Acorn computer sold into their area, regardless of whether they
were involved in winning the sale.
8.12
Mix and match
8.12
“What if the school wants various non-Acorn bits adding into their
systems?” This isn’t a problem. All that happens is that the school
simply elects to have the computers delivered to the Agent (or a dealer
of their choice) rather than the school. The Agent then adds the
upgrades, peripherals, software, etc, and delivers them to the school.
8.12
Winners and losers
8.12
In the short term, there are going to be winners and losers in all of
this. There are a number of keen dealers (such as NCS, dare I say) who
have been selling computers into education. If they are not offered an
agency, their days of selling into education are numbered as the schools
gradually realise that they can buy more cheaply direct from Acorn (at a
price less than the dealers can buy from Acorn). I fear that this could
put some dealers out of business or, at the very least, force them to
sell PCs as well/instead in order to make a living. (NCS is NOT going to
sell anything other than Acorn − we’d rather go bust!)
8.12
The Acorn Agents, of course, will be very happy because they will get a
fair margin on what they do sell and they won’t have to be watching
their backs all the time for other dealers under-cutting them. Where
schools in their area are already convinced that Acorn is the best, the
Agent simply supplies their needs as required − which shouldn’t take too
much time and effort − and they can then concentrate on winning over new
schools or winning back those who have gone over to PCs only to find
what a pain (and a cost) they are to maintain and upgrade compared to
Acorn machines.
8.12
Price drops
8.12
The remainder of the Acorn computer range has been reduced in price as
shown below. (The two monitors, as before, are the AKF52 ‘medium grain’
monitor with dot pitch 0.42mm and the AKF50 ‘fine grain’ monitor with a
dot pitch 0.28mm. These are shown as /52 and /50 in the table.)
8.12
  RRP  REP
8.12
A4000/52 HD210  £849  £704
8.12
A4000/50  £896  £751
8.12
A3020/52 floppy  £599  £528
8.12
A3020/50  £646  £575
8.12
A3020/52 HD80  £749  £645
8.12
A3020/50  £796  £692
8.12
A3010 no monitor  † £399  † £399
8.12
A3010/52  † £599  † £599
8.12
† These prices include either the Learning Curve software or the Early
Years software.
8.12
Software packs
8.12
As previously, Acorn offers some good value software packs for purchase
with the computers. The Learning Curve is unchanged (Advance + PC Soft +
demos) as is the Home Office pack (EasiWriter + Datapower + PipeDream 4
+ demos) but the Early Years pack has been revamped.
8.12
The Early Years pack now contains Betsi (interactive adventure, reviewed
8.6 p78), Music Box (music exploration package, reviewed 7.10 p78), Spex
(2D/3D planner, reviewed 7.2 p75) and Dazzle from SEMERC, a new art
package which is simple enough for Key Stage 1 and yet can be expanded
for use up to Key Stage 3.
8.12
The Early Years and Learning Curve packs add £53 to the price of the
computer (except A3010, with which it is included as standard) and the
Home Office adds £88 to the price.
8.12
Just to confuse matters, the Home Office pack is only available with the
ACB60 and the A4000, the Learning Curve is only available with the
ACB60, the A4000 and the A3010 whereas the Early Years pack is available
with the A7000 as well as the ACB60, the A4000 and the A3010! (Spot the
logic!)
8.12
The future
8.12
Quite frankly, I had begun to think that it was the beginning of the end
for Acorn with Acorn dealers waging war on one another and PC dealers
coming in and taking over. However, with the new Acorn Agency scheme and
this new range of computers, I have renewed hope for Acorn. I know it
won’t be a walk-over, but Acorn does now have something to shout about
again and does have a future in the education market. u
8.12
4Mation    14 Castle Park Road, Whiddon Valley, Barnstaple, Devon, EX32
8PA. (01271­25353) (01271­22974)
8.12
Abacus Training    29 Okus Grove, Upper Stratton, Swindon, Wilts, SN2
6QA. (01793 723347) (01793-723347)
8.12
Acorn Direct   FREEPOST, 13 Dennington Road, Wellingborough, Northants,
NN8 2BR. (01933­279300)
8.12
Acorn Computers Ltd    Acorn House, Vision Park, Histon, Cambridge, CB4
4AE. (01223­254254) (01223­254262)
8.12
Akalat Publishing   P.O. Box 231, Barton, Bedford, MK45 4HQ,
(01582­881614) (01582­881614)
8.12
Aleph One Ltd   The Old Courthouse, Bottisham, Cambridge, CB5 9BA.
(01223­811679) (01223­812713)
8.12
APDL    39 Knighton Park Road, Sydenham, London, SE26 5RN.
8.12
Atomwide Ltd   7 The Metro Centre, Bridge Road, Orpington, Kent, BR5
2BE. (01689­814500) (01689­814501)
8.12
Avie Electronics (p5)  7 Overbury Road, Norwich. (01603­416863)
(01603­788640)
8.12
Beebug Ltd    117 Hatfield Road, St Albans, Herts, AL1 4JS.
(01727­840303) (01727­860263)
8.12
CD Circle   Desktop Laminations, P.O.Box 332, Bristol, BS99 7XL.
(0117­979-9979)
8.12
Clares Micro Supplies   98 Middlewich Road, Rudheath, Northwich,
Cheshire, CW9 7DA. (01606­48511) (01606­48512)
8.12
Colton Software   2 Signet Court, Swanns Road, Cambridge, CB5 8LA.
(01223­311881) (01223­312010)
8.12
Computer Concepts   Gaddesden Place, Hemel Hempstead, Herts, HP2 6EX.
(01442­63933) (01442­231632)
8.12
Cumana Ltd   Pines Trading Estate, Broad Street, Guildford, GU3 3BH.
(01483­503121) (01483­503326)
8.12
Desktop Laminations    P.O.Box 332, Bristol, BS99 7XL. (0117­979-9979)
8.12
Hodge Electronic Services    16 Mold Road, Mynydd Isa, Clwyd, CH7 6TD.
(01244­550803)
8.12
Hugh Eagle   48 Smithbarn, Horsham, Sussex, RH13 6DX.
8.12
iSV Products   86, Turnberry, Home Farm, Bracknell, Berks, RG12 8ZH.
(01344­55769)
8.12
Kudlian Soft   8 Barrow Road, Kenilworth, Warwickshire, CV8 1EH.
(01926­851147)
8.12
Longman Logotron   124 Cambridge Science Park, Milton Road, Cambridge
CB4 4ZS. (01223­425558) (01223­425349)
8.12
LOOKsystems   47 Goodhale Road, Bowthorpe, Norwich, NR5 9AY.
(01603­748253) (01603­740203)
8.12
Millipede Electronic Graphics   Cambridge House, Hargrave, Bury St
Edmunds, Suffolk, IP29 5HS. (01284­850594) (01284­850351)
8.12
Minerva Systems   Minerva House, Baring Crescent, Exeter, EX1 1TL.
(01392­437756) (01392­421762)
8.12
Northwest SEMERC   1 Broadbent Road, Watersheddings, Oldham, OL1 4LB.
(0161­627­4469)
8.12
Oak Solutions   Dial House, 12 Chapel Street, Halton, Leeds, LS15 7RN
(0113­232­6992) (0113­232­6993) [e-mail]
8.12
Quantum Software   35 Pinewood Park, Deans, Livingston, EH54 8NN.
(01506­411162)
8.12
Renegade Software   C1, Metropolitan Wharf, Wapping Wall, London, E1 9SS
8.12
Repair Zone   421 Sprowston Road, Norwich, NR3 4EH. (01603­400477)
(01603­417447)
8.12
Swift Software   347 London Road, Hazel Grove, Stockport, SK7 6AA.
(0161­477­8405)
8.12
The ARM Club   Freepost ND6573, London, N12 0BR. (0171­624­9918)
(0181­446­3020)
8.12
US Gold Ltd   Units 2/3, Holford Way, Holford, Birmingham, B6 7AX.
(0121­625­3366) (0121­606­1822)
8.12
Warm Silence Software   St Catherine’s College, Manor Road, Oxford, OX1
3UJ. (01865­54382)
8.12
WECC   Manor Hall, Sandy Lane, Leamington Spa, CV32 6RD. (01926­413741)
(01926­413748)
8.12
Norwich Computer Services     96a Vauxhall Street, Norwich, NR2 2SD.
(01603-766592) (764011)
8.12
       email: [e-mail]
8.12
Fact-File
8.12
(The numbers in italic are fax numbers)
8.12
Government Health Warning − Reading this could seriously effect your
spiritual health
8.12
I’m beginning to realise that I might have upset a few people (moi?!) by
some comments I made concerning the way God ‘rescued NCS’ by the fact
that the Risc PCs came out at the time they did. I think I gave you the
impression that God was saying to people, “You will buy a Risc PC from
Paul Beverley, now!” Oops!!
8.12
The facts are that if the Risc PC had not come out when it did, and if
lots of people had not bought their Risc PCs from NCS, I would have gone
bankrupt. Now, I have very little control over people’s choice to buy
from NCS, apart from trying to give you a good service and tell you
about new machines a.s.a.p., and I have even less control over when
Acorn will launch new machines and how good they will be. So what I do
is pray to God − about everything − big and little, and my experience is
that God seems to look after me. So all I can do is say thank you for
rescuing me and continue to try to trust him each time another big wave
comes.
8.12
So, will we survive this latest crisis (see above)? I don’t know but I
do know that nothing that can happen to me is as important as knowing
the love of God in my life − nothing!!
8.12
P.B.
8.12
Paul Beverley
8.12
Comings and Goings
8.12
Goodbye − After over two years with NCS, Matthew Hunter is moving on to
pastures new. Thanks for all your hard work, Matthew − good luck in the
future! Hello to James Taylor who joined NCS just in time to help mail
out the last issue of Archive. We took him on when we realised Matthew
was leaving and he’s certainly keen to promote Acorns which is just as
well because...
8.12
Bad news for (some) Acorn dealers
8.12
Acorn’s new policy of selling direct to schools and using about twenty-
five ‘Acorn Agents’ is good news for them but rather dire news for the
rest of us. Since Acorn’s education price is less than the dealer price,
it means that all Acorn dealers, except the 25, have had all their
education sales taken away over night.
8.12
The other bit of bad news for Acorn dealers is that Acorn have slashed
the dealer margin by a third, i.e. to make the same profit, we will have
to sell half as many machines again as we were doing.
8.12
Is there any future for Acorn now?
8.12
Strange as it may seem, I’m more optimistic than I have been for a while
about Acorn’s future (though not too sure about our future!) As painful
as it is to many of us, Acorn had to do it. They had to make it so that
the Acorn dealers were not under-cutting one another and then being
undercut again by box-shifters. I won’t win friends amongst the other
dealers by saying this, but many dealers were migrating to PCs anyway.
Because of all the inter-Acorn undercutting, there is often more to be
made by selling PCs than Acorns − and there is no sentiment in business.
I know of one large (so-called) Acorn dealer who sold a huge network of
PCs into a school against a local dealer who was trying to get them to
buy Acorns.
8.12
Acorn knew that, to survive, they would have to help those dealers who
were genuinely helping them, i.e. selling Acorn kit above PCs. Now that
the Acorn Agents are fighting the PC dealers rather than other Acorn
dealers/box-shifters, they can make some inroads into the PC market −
and they are doing so. There have been quite a few cases recently where
Acorns have won contracts in schools which have not previously been
Acorn schools. And with the new A7000 and Risc PC 700 machines, we’ve
got more to fight with, so yes, there is still a future for Acorn.
8.12
That’s it for now. Happy reading!
8.12
P.S. Special thanks to all who got articles in to me extra fast − I
couldn’t fit them all in after all that! Sorry!!
8.12
The New Acorn A7000
8.12
Use whichever of the two photos
8.12
you think will come out better
8.12
in black and white
8.12
ACB75 vs ACB45
8.12
Twice the HD size
8.12
Twice the VRAM
8.12
Improved OS
8.12
Improved sound
8.12
Faster processor
8.12
Slightly cheaper
8.12
!
8.12
Products Available
8.12
Archive CD − Jumping unashamedly on the bandwagon, NCS has now released
an Archive CD­ROM! The contents are as follows...
8.12
− Archive Impression Files − all of the Archive magazines from 4.5 (the
first one to be done on Acorn machines rather than Macs) up to and
including this one (8.12).
8.12
− Archive Words discs, again from 4.5 to 8.12 − these are text files of
all the articles in those magazines so you can search through for that
elusive article (or was it just a hint?) that you remember reading in
Archive... somewhere!
8.12
− Archive Products Available file − the text of all the Products
Available columns in all the Archive magazines right back to Volume 1,
Issue 1! (“Did anyone ever produce a program for Acorn machines to count
hen’s teeth?”)
8.12
− Archive Monthly Program Discs right from Volume 1 to the present
issue. It’s quite fun looking back at some of the ‘amazing programs’ we
published nearly eight years ago!
8.12
− Archive Utility Discs all eight discs as detailed in section 28 of the
Price List.
8.12
− Archive Hints & Tips Discs − the text of all the hints and tips ever
published in Archive, right back to the days of good old Arthur (the OS
before RISC OS).
8.12
− Archive Glossary − a glossary of almost 300 technical Acorn-related
words, with over 9,000 words of explanation as to what they all mean.
8.12
− Archive PD Discs − Lots of the old ‘Careware’ and ‘Shareware’ discs
that we used to distribute.
8.12
− Archive Multimedia Swap Shop − Paul Hooper has sent us all the best
multimedia applications/binders that he has collected.
8.12
− PLUS a special guest appearance of the oldest-established Archive
author, who has written articles in every single Archive magazine
(barring about two in the first volume) for eight solid years.
8.12
Our very own Gerald Fitton has sent us sample discs for his three disc
subscriptions: Z-Line for users of Fireworkz, PipeLine for users of
PipeDream and I­Line for users of Style, Publisher and P-Plus.
8.12
The Archive CD-ROM costs £15 inc VAT to non-subscribers or £12 to
subscribers.
8.12
As a special launch offer, we will make it available for £8 if purchased
at the same time as renewing your subscription. This is a special offer
strictly until Friday 15th September only. (You may take advantage of
this offer by renewing your subscription now, even if it is not due
until later in the year. You may even avoid an increase in the
subscription rate by doing so!)
8.12
AudioManager − CD Circle have produced an 8-bit mono sound card which
plugs into the parallel port of the Risc PC to offer sound facilities to
the PC card. The kit includes the dongle with through-printer facilities
(which supports all known dongles), combined speaker and microphone with
battery holder input/output/9v power socket and touch button high/low
volume control. Also included is a Windows Voice and Icon enhancement
feature and the Microsoft Home CD Sampler, with previews of over 55
programs and 8 Windows games. Windows and 8Mb of memory allocated to the
PC card, are required to use the package. The price is £85 inclusive, or
£70 to CD Circle members.
8.12
Big Ben Club Open Day − The Dutch Acorn Computer User Society, the Big
Ben Club, will be holding their 13th annual open day on Saturday
September 23rd. The event will be held at the Community Centre, “De
Kiekmure”, Tesselschadelaan 1, at Harderwijk between 10 and 4. Admission
is free to club members, Hfl. 7,50 to non-members. More information can
be obtained by contacting Big Ben Club, P.O.Box 1189, 6801 BD Arnhem,
The Netherlands. A bulletin board is also available on (31) (0)20-
6631849, and a fax machine on (31) (0)70-3663194.
8.12
Canon printers − Canon have changed their range of bubblejet printers by
revising earlier printers and adding of some entirely new products.
8.12
BJC70 − Portable colour and mono printer, 360 dpi in colour, 720 dpi
with smoothing in mono − £310.
8.12
BJ-200ex − Mono, 360 dpi (720 dpi with smoothing) − £260.
8.12
BJC-4000 − Colour and mono, 360 dpi colour, 720 dpi mono with smoothing
− £320.
8.12
BJ-600e − Colour and mono, four separate colour ink wells, 360 dpi in
colour, 720 dpi in mono, with smoothing − £445.
8.12
These printers will work with Acorn !Printers 1.28c, although some
resolutions may not be available (the BJC600 driver does not support the
720×360 dpi mode, for example). For additional speed, the Canon
Turbodriver also supports all the above printers, although again some
resolutions may not be available. Add £45 to the above prices if you
would like a Turbo Driver as well as the printer, which includes a
special printer cable. If you plan to use the Acorn drivers, and do not
have a printer cable, we can supply a standard cable for £10.
8.12
Cross Stitch − iSV Products’ cross-stitch design package allows sprites
to be used as input, to produce a full cross-stitch pattern, using up to
64 colours from 512 named industry-standard thread colours. The design
can be saved as a drawfile for importing into DTP packages, as a colour
or black and white design. It gives support for a wide variety of
materials, and provides automatic conversion of sprite colours to named
colours, automatic calculation of finished design size, definable
background colour and over 10,000 stitches per pattern. The price is
£21.50 including p&p from iSV or £20 through Archive.
8.12
DEC_dATA on WWW − DEC_dATA now have their brochure on the World Wide
Web, including product information and prices of Acorn Clipart and
multimedia products. The URL is ‘http://www.zynet.co.uk/decdata/’. The
DEC_dATA e-mail address is at [e-mail].
8.12
Digital Darkroom 2 − This is a TransGraphic viewer from Desktop
Laminations, supplied with a version of TransPCD which will read Kodak
and all Corel Professional PhotoCD-ROMs. Facilities include variable
size thumbnails and slideshow. It will recognise other Transloaders,
such as TransTiff supplied with Impression. DL also produce a set of
loaders to use with this application − see below. The price is £45
inclusive, or £35 for members of the CD Circle.
8.12
Fire & Ice is a game which has already received good reviews from other
platforms, notably Atari and Amiga. Now it’s been converted for the
Archimedes by Paul Chapman and is available from Renegade at £25.99 (£24
through Archive). For more details, see the review on page 40.
8.12
Font Trix PRO − This package from iSV is an enhanced version of the Font
Trix application supplied with their Font Designer’s Toolkit. It will
load RISC OS 2, 3 and Base0 outline fonts, make real outline fonts
(rather than transformed versions), will auto-adjust kern-pairs, make
new styles, load and save transformations, has automatic shifting of
scaffold lines and can repair faulty scaffolding, and can adjust
skeletons and bounding boxes, etc. The price is £25 (+£1.50 p&p) from
iSV (or £24 through Archive), or £15 (+£1.50 p&p) for owners of the Font
Designer’s Toolkit.
8.12
Game On! Release 2 − The ARM Club have released a new version of their
Game On! software, which allows many non-Risc PC compatible programs,
particularly games, to work on the Risc PC. The new version has a
redesigned front end and database for improved speed and ease of use.
New features include support for both RISC OS 3 and 3.1 mode extension
modules, and a method for preventing games reducing the font cache to
zero. Support is included for more games than the earlier releases, as
well as other applications such as 65Host, Satcom, and some music module
players (such as trackers) are also supported. The database has been
updated, with all games tested for compatibility with and without Game
On installed. The price is £15 inclusive from the ARM Club, or £5 to
upgrade from the earlier release.
8.12
Indigo CD-ROM drives − Cumana have dropped the prices on their Dual-
Speed Indigo CD-ROM drives for the Risc PC, the CAA300i is £125 +VAT
+p&p or £150 through Archive, the CAA300iA (with audio mixer) is £175
+VAT +p&p or £205 through Archive. The range has been extended with two
quad-speed variants, the CAA340i (£199 +VAT +p&p − £235 through Archive)
and the CAA340iA (£249 +VAT +p&p − £290 through Archive), which make use
of the IDE/ATAPI interface and do not need an additional controller
card. Alternatively, the CXX441(£199 +VAT +p&p − £235 through Archive)
is a quad-speed SCSI drive − if you do not already have one, you will
also need a SCSI card to use it.
8.12
Loaders/Savers for Impression − This is a set of extensions to Style
(3.06 or later), Publisher (4.04 or later) and Publisher Plus (5.04 and
later). When installed, they give extended facilities for importing and
exporting Rich Text Format (RTF) files (as used by Microsoft Word and
the Acorn PocketBook) and WordPerfect 5.1 files, which will be of great
help to people who regularly need to exchange files with other
platforms. It is important to note that it will only transfer the text,
and most style/effect information, but not graphics or some text
formatting information (such as multiple columns and page size details,
which are handled differently on Impression). Two other utilities are
also included which set up translation tables for fonts and characters,
so you can configure the way in which transferred documents appear. The
RTF Loader/Savers cost £29 +VAT +p&p from CC or £34 through Archive.
8.12
MacroLife − This is an excellent multitasking version of Conway’s Game
of Life that allows for huge life planes which can be viewed at any
scale and scrolled around in a window while it’s running. MacroLife has
now reached version 1.8 and is now RISC OS 2 compatible, faster to load
and even uses a little less memory. The full program can be obtained by
sending a cheque for £8 to Chris Taylor at his new address, 32 Burghley
Court, Great Holm, Milton Keynes, MK8 9EL (01908-569556). Four pounds of
that will be donated to the charity, Motivation. (See the review on page
35.)
8.12
Magpie CD-ROM − Longman Logotron have released a new ‘value added’
version of Magpie, their multimedia application. It is supplied with
ready-to-run projects created by existing users, and a wide range of
samples, clipart, and sound samples. Magpie allows pupils to create
multimedia projects by combining a variety of resources, including
words, pictures, video and sound on the same ‘page’ of an electronic
book, using simple drag and drop techniques. The single user version
costs £59, a primary site licence £190 and a secondary licence £330.
Registered Magpie users can upgrade to this latest version for half
price. All prices are exclusive of VAT and postage. (£69, £215 and £370
respectively through Archive)
8.12
Movie FS − Warm Silence Software have updated and renamed their
extensions to Replay, allowing it to playback films and samples not
normally supported. File formats include Video for Windows (.AVI),
QuickTime (.MOV), Animator Pro (.FLI), and WaveForms (.WAV). The price
is £26.42 (no VAT, including p&p).
8.12
Online Magazine − This is yet another Acorn magazine that is produced
“by enthusiasts for enthusiasts” to refute our claim in the advertising
blurb we have been sending out lately. Online Magazine has been going
for four years now as “a publication for (hopefully) light, humorous and
basically easy reading about Acorn related products. It is a decidedly
‘supplemental’, non-technical publication (as much as is possible with
the subject matter) aimed at teachers and school technicians.” says John
Hughes, Co-Editor. John is co-editing because John Hammell, the Founding
Editor is in and out of hospital for horrific-sounding operations to his
legs following a terrible road accident some years ago. Hope things are
soon improved, John!
8.12
The issues of Online Magazine that John sent to me are all 50 − 60 pages
A5, mostly filled with articles although there are a few adverts. It
seems quite good value at £17 for 12 issues. Send cheques, made out to
‘Online Magazine’ to John Hughes, 74 Kilbagie Street, Kincardine, Fife,
FK10 4QX.
8.12
PickAPic − Hugh Eagle now has an updated version of his PickAPic clipart
viewer and organiser available. It should be available from PD
libraries, including APDL. Textual descriptions can now be included, and
pictures can be displayed much more quickly, by storing thumbnails of
the images in a special directory.
8.12
Portfolio − A new presentation package from Warwickshire Educational
Computing Centre (WECC). The package will produce a slideshow from a
directory of images (including Sprite and Draw, in normal and Squashed
formats) and a number of foreign formats, including Windows BMP and
JPEG. Display is full screen, in whatever screen mode is selected at the
time, and control can be automatic, manual or by script file. To start a
display, simply drag a directory of images to the PortFolio icon on the
iconbar. Sounds can also be associated with screens. A companion
program, Gallery, allows multiple images to be printed eight to a page,
including the full filename if desired. The prices are £25 (Single user
and primary Site Licence) and £29 (secondary Site Licence) for
Portfolio, and £15 (S/U and primary S/L) and £25 (Secondary S/L) for
Gallery.
8.12
Printers 1.28c − We are now able to supply the latest version of Acorn’s
printer manager !Printers. It is supplied with two discs, and paper
documentation, so the price is £5 to cover duplication and p&p.
8.12
Proteus − Cumana have released a combination drive, which integrates a
quad speed CD-ROM drive, and a 650Mb rewritable disc, which can be
formatted and partitioned in the same way as any SCSI hard disc. The
removable discs are housed in a permanent plastic case, like a floppy
disc. The access time is 165ms, and the average transfer rates are
between 518 and 1141 Kb/s. The drive needs a SCSI interface to operate,
and is available in internal (£549 +VAT +p&p, or £635 through Archive)
and external (£699 +VAT +p&p, or £805 through Archive) versions.
8.12
Risc PC 486 cards − At the time of writing, projected availability of
the PC cards for the Risc PC is still set at the end of August. The
special price of £99+VAT will end after 31st August, unless the card is
purchased with a Risc PC. After that time, anybody who is not purchasing
a Risc PC will have to pay the full price of £199+VAT. If you have been
holding off placing an order until the cards are more freely available,
then you need to order as soon as possible, and certainly before 31st
August. (We gather that the new batch of PC cards are the same as
existing cards, i.e. they do not yet have any enhanced capabilities.)
8.12
Technology & Design (NW SEMERC) − This package allows pupils to carry
out a design brief for something within a fictional town, covering the
community, the environment, at home, at play, at school and recreation,
using a large number of Acorn Replay and photographic images. The price
is £59 +VAT +p&p, and the package requires My World 2.
8.12
Three Little Pigs (Tempest Publishing) − For children just starting to
read, this package aims to develop numeracy skills, as well as literacy,
and an awareness of their environment. It comprises an interactive
talking story and the characters and themes appear in a set of related
activities. The price is £25.49 +VAT +p&p, or £31 through Archive.
8.12
Trans-Graphic Loaders − A new set of graphics loaders for use with
Artworks, Style and Publisher, Ovation Pro and Digital Darkroom 2 (see
above). The Trans loaders are produced in conjunction with Computer
Concepts. The pack includes translators for BMP/DIB files, GIF
(including conversion of attached text), Windows ICO files, PCX and WPG
files. The price is £45 inclusive from Desktop Laminations (£35 to
members of the CD Circle).
8.12
Review software received...
8.12
We have received review copies of the following: •extASM assembler and
AOF utility (lu), •Strike (e), •Portfolio (e).
8.12
e=Education, l=Language, u=Utility. u
8.12
Archive Monthly Disc
8.12
u Addsprites utility from Andrew Clover, Doggysoft − page 21.
8.12
u Beginner’s Basic program from Ray Favre − page 56.
8.12
u C++ sample program from Tony Houghton − page 65.
8.12
u Files from Gerald Fitton’s Column − page 23.
8.12
u Sample Keystroke definitions from Stuart Halliday − page 72.
8.12
u Application/binder catalogue from Paul Hooper’s Multimedia
Column − page 15.
8.12
u Files from Keith Hodge’s Risc PC Column − page 22.
8.12
u An article from Simon Anthony − it’s fun, but it’s too general for
inclusion in the magazine.
8.12
u Two articles about installing Windows ’95 from Dave Harris and Mike
Clarkson.
8.12
Avie
8.12
New artwork
8.12
The Engineer Speaks!
8.12
Ray Maidstone
8.12
Dirty CDs!
8.12
Following on from last month’s whinge about dust, I ought to point out
that CD-ROM drives are just beginning to show similar signs of
contamination. Fans that use unfiltered air, fill up the drive’s optical
heads, scanning mechanisms and disc trays. Whilst I don’t mind being
paid to clean these, I’d rather help people to help themselves than
repair things! If you have a CD-ROM drive in your computer, fans and
filters should be fitted as described last month. CD drive cleaning kits
are in the same league as video and floppy cleaning kits, i.e. only
suitable for superficial use. Nothing replaces cleaning by a competent
engineer. CDs should be cleaned from the centre to the outside using
optical grade lint or some other soft, non-abrasive material.
8.12
IDE drives
8.12
To clarify last month’s comment about IDE drive communication, the
general rule is that cables should be no longer than 15“ (about 40cm).
The positioning of drives along the cable can lead to problems with
hardware items recognising each other. Experimentation is needed − I
have found that some set-ups like to have the motherboard in the middle
of the cable with a drive at either end, whereas others like to have the
main pcb at one end of the chain. Some 3½” removables will only operate
as the master drive, and some combinations simply refuse to work at all!
8.12
Screen savers
8.12
− the truth behind the myth! There are several screen savers on offer,
but many of these only address part of the problem. Whilst it is nice to
get maximum life from the phosphor dots of your tube, it is also very
advantageous to look after the unseen workers, namely the line output
stage and the power supply. For various technical reasons, the screen
savers that simply blank the screen do no favours to the power supply,
and certain kinds can even damage the line output stage. Some display a
variety of pretty pictures, which may draw the attention of passers-by
and prevent burn-in but, as these are usually bright enough to view
under normal conditions, they are not very effective in helping the
whole monitor. From an engineering point of view, I have not seen a
screen saver that fits all the requirements, and so I designed my own a
while back that did. If you would like to write your own, the ideal
criteria are: no phosphors brighter than 20%, between 20% and 50% of the
screen covered, and no static pixels. This looks after everything!
Basically, the display should look like an ever-shifting night sky, not
the Star Trek radial starfield type of screen saver so often seen.
8.12
Well, strike me!
8.12
Finally, on a seasonal note, we’ve been very grateful for the recent
heavy storms − repairs have flooded in! Seriously though, when there is
thunder and lightning around, please disconnect your equipment, if at
all possible. It does not take a direct strike to cause unnecessary
expense and heartache − fluctuations in power from the mains can do
quite serious damage. I have also been sent some call-logging equipment
and several modems which have been damaged irreparably by the phone
system being taken out by the storms, so don’t forget to unplug hardware
from phone sockets as well! u
8.12
New Machines − A Technical Look
8.12
Matthew, James & Paul
8.12
RISC OS 3.6
8.12
(Matthew Hunter’s article in Archive 7.8 p13, detailed the differences
between RISC OS 3.1 and 3.5. All we will do here is to cover the
advances made to reach RISC OS 3.6, as supplied in the new computers.)
8.12
Once again, the upgrade consists of an updated version rather than a
completely new system, and, at first sight, very little seems to have
changed since RISC OS 3.5, certainly not in the user interface, although
there are some subtle changes.
8.12
Apps
8.12
The Apps system has changed again. The major applications have been
moved into ROM, while some of the less frequently used applications
remain in the Apps directory on the hard disc, and are added to the
iconbar Apps folder during the boot sequence. This has the advantage
that the major applications are in ROM, and immediately accessible,
while retaining the versatility of adding applications simply by copying
them into Apps on the hard disc. The directory display shows the list of
standard applications available through Apps, of which Alarm, Chars,
Draw, Edit, Help, Paint, and Printers are stored in ROM.
8.12
With many of the applications in ROM, the memory requirements are in
some cases substantially less than in RISC OS 3.5. The table below shows
the usage on a Risc PC 700, and the old Risc PC 600. If you run all the
applications that are in ROM, they take up 280Kb compared to 1208Kb when
run from disc on RISC OS 3.5.
8.12
The applications have gone through what are, for the most part, minor
changes, although now both Paint and Draw can load JPEG images directly
(i.e. no need to use ChangeFSI). In the case of Draw, the image is
retained within the drawfile as a JPEG image and is decompressed
directly to the screen. Draw creates a “JPEG Workspace” − a resizable
dynamic area the size of which is dependent on the width, in pixels, of
the image. There is a noticeable slowing down in rendering the image in
this way over a sprite, but decompression is considerably faster than
ChangeFSI, and it benefits from the much smaller file size of JPEG
images. The only restriction is that JPEGs cannot be rotated within a
drawfile. Draw also has additional export options, as shown on the menu
below, including saving as a PostScript file. (To make use of this
option, you will need a PostScript printer driver loaded.)
8.12
CDFS and audio
8.12
For compact disc users to take advantage of the audio mixing capability,
there is a new ‘Volume’ menu item on the CDFS icon on the iconbar. This
allows you to set the volume of music CDs which are being mixed with the
computer’s sound system.
8.12
There is also an option within Configure to select whether or not to use
16-bit sound, since it could clash with software which does not access
the sound system through official ‘channels’.
8.12
System changes
8.12
In increasing the ROM size from 2Mb to 4Mb, Acorn has given itself room
to expand the facilities.
8.12
Device drivers − Device drivers are now included for PS2 type mice,
although only the A7000 hardware currently supports them, and CDFS is
now included as standard (v2.28) along with several softloadable drivers
for specific CD-ROM drives (ATAPI and the EESOX drivers for Chinon,
Hitachi, Philips, Sony and Toshiba). DOSFS has also been updated to
0.62.
8.12
Networking − There have been substantial additions to the networking
available as standard. All the Access and Ethernet modules are included,
as well as the TCP/IP modules for Internet connection (although you will
need additional software to access the Internet). All that is required
to create a working network is two or more RISC OS 3.6 computers with
Ethernet cards, and cables to connect them. Access Plus software
(allowing password protection of directories on your hard disc) and
Access CD Share are provided on hard disc.
8.12
Toolbox − All the Toolbox modules, as supplied with the Acorn C/C++
package, are included in the ROM, reducing the overhead involved in
using Toolbox applications. Unfortunately, some of the modules are
earlier versions than those supplied with the recent update to C/C++.
Even so, the improvements offered by the Toolbox outweigh the memory
overheads − and remember that, as with the shared C-Library, only one
set of modules is needed, no matter how many applications are using
them.
8.12
System resources − These have changed very little. Some of the small
utilities which were stored on disc in RISC OS 3.5 have moved into ROM,
such as addapp and repeat, and there is a new directory within Choices
which contains the options for Printers. Previously, they were stored
within the !Printers directory but, of course, that is not possible with
!Printers in ROM.
8.12
Configuration − Configure is still run by double-clicking !Boot from the
desktop. It now contains options to set the number of CD-ROM drives
available, whether to use 16-bit sound, and also a mouse type which now
includes PS2 mouse support.
8.12
How fast is the ARM700?
8.12
Following on from the JPEG decompression speed tests in the last
article, Matthew repeated them on the new machines to give some
comparisons. If you check back with the original, you will see that
there appears to have been a slight degradation in performance. This is
because these tests were carried out with the latest version of
ChangeFSI, which offers more facilities but does seem slower overall.
The MHz column gives the clock speeds of the different machines, and
therefore the maximum theoretical speed improvement.
8.12
All the tests were carried out using the sa01 image from the images
directory, and ChangeFSI v1.12. First in 480×352 resolution (remember
the A7000 does not have VRAM):
8.12
and then at 800×600:
8.12
As expected, the A7000 fails to keep up with the Risc PC 600 due to the
lack of VRAM, as shown by the large drop in performance as the
resolution and number of colours increase. The Risc PC 700 performs
better than the 600, the increase being around half of the increase in
clock speed which is not unusual since other components in the system
will not be operating any faster.
8.12
The machines used for the tests were:
8.12
(a) an original Risc PC 600 with 2Mb VRAM and      12Mb DRAM,
8.12
(b) an A7000 with no VRAM and 8Mb DRAM,
8.12
(c) a new Risc PC 700 with 2Mb VRAM + 8Mb      DRAM.
8.12
A second floating point intensive test was also carried out, which will
hopefully be of more use when the ARM700/FPA11 is released. The test was
raytracing an image 250×200 pixels using POVray 2.2. The Risc PC 700
took 12m 43s, the Risc PC 600 took 15m 45s whereas a 25MHz A5000 with
FPA10 took only 2m 52s. For interest, I have also run the test on a
number of PC cards and real PCs. The standard Acorn PC card takes around
26 minutes, the DX2/66 took 38 seconds (as did a true DX2/66), the DX2/
80 takes 32 seconds, and a Pentium 90 reduced the time to 11 seconds, so
there is still some work for Acorn to do!
8.12
RISC OS 3.6 for all?
8.12
Owners of current Risc PCs will be pleased to hear that a “RISC OS 3.6½”
upgrade will be made available, although not until the New Year. This
is, presumably, because they had to concentrate on getting a version
working with the new machines and it can take months to get ROMs blown.
Also, there are potential problems in handling hard drives which have
already been formatted with the old version of filecore, so the upgrade
is not a task to be undertaken lightly.
8.12
Hardware changes
8.12
The changes in the underlying hardware of the Risc PC have been mostly
minor ones, although the motherboard has been changed. All the main
components are in the same places, but it is obvious that some of the
sound hardware has been altered to support 16-bit sound and the audio
mixing facilities, including a new link which takes the CD-audio
directly off the CD-ROM drive to the motherboard.
8.12
The A7000 uses a completely new board, on which the ARM7500 (clocked at
32MHz) is surface mounted, as is the ARM250 on the A3010/20 and A4000.
It is housed in a metal case (to keep the cost down) but with a plastic
shroud to make it tone in better with the 600/700 machines. Service
engineers will be pleased to hear that the metalwork is more user-
friendly than the sharp edges of the A5000 case and drive shelf!
8.12
The speed of the ARM610 supplied in the Risc PC 600 has been increased
from 30 to 33MHz, while the ARM710 is clocked at 40MHz (Acorn say this
will deliver 32MIPs). All Risc PCs are now shipped with at least 4Mb of
RAM, and Conner hard drives are still used.
8.12
The ATAPI CD-ROM drive is manufactured by Sony, and is a tray-loading
drive. However, it has a mechanism to enable the drive to operate in
tower mode. There are four rubber ‘feet’, which can be swung into place
over the CD to stop it falling off. The idea is not to turn them in and
out every time you put in a CD but to use the two ‘lower’ feet,
depending on which side the machine is tipped. The A7000 does not come
with feet, so we feel it is best kept horizontally mounted or you will
block the ventilation holes. Also, since it is a single fixed-size box,
there is little point in using it in tower mode.
8.12
Wot?! No VRAM?
8.12
You may well be wondering why the A7000 has been made with no VRAM
facility at all − that sounds rather limiting in terms of the graphics.
Well, compared to the Risc PC 600/700, it is.
8.12
The first thing to note is that the ARM7500 is a monster chip with
almost 300 pins! If it had to have all the connections for VRAM as well,
it would push the cost way up again.
8.12
Why then did Acorn bother to develop a computer that had no VRAM? Well,
I’m not sure that they did! I think they developed a pcb for a set-top
box and decided that it wasn’t much extra work to put it in a computer
box and sell it as an A7000 − another example of the kind of spin-off
that ARM Ltd and Online Media can produce for Acorn Computers.
8.12
Wot?! Only 2Mb VRAM?
8.12
Yes, I’m afraid that we have not yet got the 4Mb of VRAM that some of us
were hoping for. The technical issues involved with processor speeds,
I/O speeds and operating system software were just too much for Acorn to
justify the development work needed for a relatively esoteric gain. How
many of us can afford the kind of 21“ monitor needed to do justice to a
machine with 4Mb of VRAM? One day... u
8.12
Small Ads
8.12
(Small ads for Acorn 32­bit computers and related products are free for
subscribers but we reserve the right to publish all, part or none of the
material you send. Sending small ads on disc is helpful but not
essential. Ed)
8.12
210Mb IDE HD £60. 110Mb IDE HD £40. Both have been used in a Risc PC.
Wearnes IDE CD­ROM drive (need to buy driver software at £19 +VAT) £40.
RISC OS 2 PRMs (still useful) £25. All plus £5 p&p unless collected.
John on 01328­864177.
8.12
8Mb SIMM, £200. Dave on 0181­992­1720.
8.12
A3000 2Mb computer, Philips colour monitor, LX400 printer £450 o.n.o.
Similar system but with Acorn colour monitor £450 o.n.o. Phone
01773­872927.
8.12
A3000 1­4Mb u/g IFEL £50. Hazel or Pat on 01375­375514.
8.12
A3010, 2Mb RAM, 14 months old, RISC OS 3.1, Philips colour monitor,
games inc. Flashback, Stunt Racer 2000, Lemmings, Speedball, Chocks
Away, E­Type 2, excellent condition, £425. Phone 01732­454707.
8.12
A4000, 2Mb RAM, 80Mb HD, and AKF18 monitor. Includes Advance software.
Hardly used £575. 300Mb SCSI drive, £125. CC scanner interface (card
only) £50. Phone 01736­63918.
8.12
A4000, multisync monitor, 4Mb RAM, 80Mb HD, lots of quality software,
wordprocessing, graphics, games, music, educational, etc. £550 o.n.o.
After sale help/advice available. Phone 01403­266728.
8.12
A5000, 4Mb RAM, 100Mb HD, RISC OS 3.1, Eizo 9060S multiscan monitor,
Acorn I/O+Midi podule £850 o.n.o. HP 500C colour printer £200. John
Savage on 01525­237625.
8.12
A5000, 4Mb RAM, 120Mb HD, RISC OS 3.1, with Taxan 775 monitor. Excellent
condition. £650 for quick sale. Mike on 01903­815976 after 6.
8.12
A5000, 4Mb RAM 80Mb HD, AKF50 monitor £700. Phone 0131­447­8624.
8.12
A5000, 4Mb RAM, 100Mb HD, RISC OS 3.1, Eizo 9060S Multisync monitor,
Serial Port High Speed Dual Serial Card, PC Emulator, £800 o.n.o. Paul
Moore on 01928­511060 (day) or 01606­871872 (eves/w/e).
8.12
A5000, 33MHz 80Mb HD, 4Mb memory, AKF50 monitor, PC Emulator (DR DOS 6),
EasiWriter, Datapower − all for £750. Also Ovation £30, Resultz £30.
Phone 01462­682961 (eves).
8.12
A5000LC, 4Mb RAM, 40Mb HD, original monitor & manuals, some software &
games £550. Phone 01903­893211 (not a.m.).
8.12
A540, 8Mb RAM, RISC OS 3.1, 120Mb SCSI HD, Acorn SCSI, Eizo 9060S
multisync monitor £690. Software includes EasiWriter, PipeDream 4 and
Interdictor. Phone 01342­714905.
8.12
A540, 8Mb RAM, 120Mb SCSI HD, RISC OS 3.11, no monitor. Error messages
almost unheard of. Best offer, exceeding a reserve, within two weeks of
this advert. Phone Jim on 01366­385824.
8.12
Aleph One 486SLC PC podule, 50 MHz, 4Mb RAM !PC Software v1.59, Windows
drivers, DR DOS and manual. Fits A400’s, Risc PC etc, £290. Phone
01342­714905.
8.12
Canon BJ330, A3 BubbleJet printer, as new, still boxed, with printer
cable and cartridge, £200 o.n.o. Genesis Professional, unused,
unregistered, £90. Gordon on 01899­308562 after 6.
8.12
CD­ROM offers − ProArtisan 2CD £50 (inc upgrade voucher to ProArt24),
Revelation 2CD £50, CC ScanLight 256 with latest drivers £100,
Illustrated Works of Shakespeare £10, Holy Bible £10, Sherlock Holmes
£10, Space Encyclopedia (PC only) £20. Postage extra, or collect. David
on 01752­840027, after 6 or w/e.
8.12
Epson GT6500 − A4 Colour scanner, parallel with Irlam ProI­mage
Software. £400. Phone 0114­261­9444.
8.12
Oak SCSI, external 45Mb HD & PSU cased with SCSI podule 1.16, all leads
£60 inc p&p. Risc Developments’ Hard Disc Companion, v2.52, £25. Ernie
Cobbold on 01493­740557 (eves).
8.12
Syquest 105Mb removable drive, 3½“, internal IDE with cartridge and
cable, £180. Phone 0114­261­9444.
8.12
Wanted urgently at a reasonable price, the old version of Notate (i.e.
not Notate 2) and Poster. Any good value offers: Phone 01734­666184
(don’t be put off by the ansaphone).
8.12
Wanted − Removable IDE hard drive (cheap as it is only to be used for
experimental purposes). Micro Librarian Systems on 0161­449­9357.
8.12
Watford MkII Hand Scanner, (4“) £75. Toner Set for Qume CrystalPrint inc
3 toner cartridges. £60. Steve on 0181­530­7104 (eves). u
8.12
Multimedia Column
8.12
Paul Hooper
8.12
Swap Shop − The future
8.12
The Swap Shop has undergone a major transition in the last few months. I
was aware that there were a lot more people in the Acorn world who were
producing good multimedia applications than read Archive. To publicise
the Swap Shop further, I contacted a couple of the other magazines and,
as a result, we have added over twenty new applications to the Swap
Shop, bringing the total to just under 100 different applications! It
has also lead to a large increase in the amount of post that I have to
reply to. Couple this with an increase in my personal work load, and I’m
afraid I have fallen a little behind with the letters! If you are still
waiting for a reply, please bear with me! Just to give you an update on
the applications in the Swap Shop, I have included a small Magpie binder
on the monthly disc which lists them all.
8.12
I hope in the not too distant future, to make a CD­ROM of all the
applications/binders within the Swap Shop available to all readers for a
modest cover charge. This will include all the readers for the
applications but with so many applications being created every day and
landing on my desk, I’m afraid it will never be entirely up-to-date.
8.12
(I have just suggested to Paul that they go on the Archive CD − and he
seems agreeable − so if you have contributed, we’ll see if we can
arrange some sort of special discount price. Ed.)
8.12
Ultima − The next generation?
8.12
I have always liked NW SEMERC’s Optima as a basic multimedia program. It
is simple and effective but can produce some quite stunning results. Now
the guys from Oldham have produced an improved and more advanced
version, called Ultima. I received my review copy the same day as an
urgent plea from Paul to do an article for an early release of Archive,
so I have had little time to play with it yet. But some of the example
programs provided with the package are excellent. I shall do a full
review for the next issue.
8.12
One of the most obvious changes is that Ultima has a toolbar down the
side of the window, similar to Draw, which brings me on to my next
subject....
8.12
Toolbars?
8.12
I know this is not really the place to sound off about this subject, but
if you can’t complain in your own column, well where can you complain? I
use my personal computer every day, along with all sorts of other Acorn
computers at work. During an average day, I will use Impression,
Fireworkz, Photodesk, Draw, Paint, CableNews II, Magpie, Genesis and
many other programs. The one thing I used to value about Acorn machines
was that it didn’t really matter which program you were using because
the way you interacted with the program was fairly consistent. You used
the menu button to play around with what was underneath it.
8.12
Many software houses now seemed to have abandoned the idea of using the
menu button and have, instead, implemented ‘toolbars’. I think toolbars
are a good idea, but I wish there were some sort of consistency about
them. Just taking my list above, look at the variations:
8.12
− Impression: Attached along the top of the window
8.12
− Fireworkz: Attached along the top of the window
8.12
− Photodesk: Attached along the bottom of window
8.12
− Draw: Attached down the side of the window
8.12
− Paint: Detached toolbar
8.12
− Edit: No toolbar
8.12
− CableNews II: Attached along the top of window
8.12
− Magpie: Detached toolbar
8.12
− Genesis: No toolbar
8.12
− Ultima: Attached down the side of the window
8.12
If Acorn themselves can’t be consistent (Paint, Draw and Edit) then it
is hardly surprising that other software houses don’t know which
standard to follow. If anyone at Acorn does read this, can I ask for a
definitive ruling on toolbars, please?
8.12
Acorn multimedia in action
8.12
Following the editor’s policy of trumpeting Acorn hardware and software
in action, I thought readers might like to know about a project that I
was recently involved in. Anglia TV produce a CD­ROM written by Gareth
Davies, all about Castles. The company I work for (Lindis) was
commissioned to produce three touch-screen booths for English Heritage
to be placed on some of their sites and to be used by the general
public.
8.12
These are based on Risc PCs with custom-built booths. The computers have
duplicate hard drives with a back up copy of the software on the second
drive and automatic failure detection to boot in the second drive if the
first fails. The software was authored using Key Author. With much
cooperation between Anglia TV, Gareth, English Heritage and many others,
these booths are now up and running. Two booths are in operation in
Dover Castle and one is about to be placed in Orford Castle. So if you
live near either of these locations, go along and see Acorn multimedia
in action.
8.12
There is also a Genesis application about Beatrix Potter in the Lake
District, but I haven’t any more details − if anyone does, please let me
know. Are there any other examples that I may have missed? If you have
authored, or know of, an application, please write and let me know
because I am trying to build up a portfolio of examples.
8.12
Genesis for Windows again
8.12
Having now had time to experiment with Genesis for Windows, I can at
last report some success. The first thing to realise is that the Windows
version is the equivalent of Genesis Plus or Genesis II. This means that
anything written by Genesis Professional is not going to work in the
Windows version without a lot of modification. For a Professional or
Project to run, you must not use subdirectories for storing resources,
and the ON OPEN event does not appear to work. In fact, the second page
has opened but remains hidden behind the first. One quick solution is to
use AFTER 1 SECOND rather than ON OPEN.
8.12
The other problem is the way a PC renders fonts. It will not recognise
the keyword ‘FONT’ in a TEXT frame, so this needs to be replaced with
STYLE, as shown below. First the RISC OS version:
8.12
DEF FRAME “Thu,15 Jul 1993.14:16:55;2”
8.12
TEXT “text01”
8.12
FONT “Jotter”
8.12
SIZE 480
8.12
HCENTRED
8.12
FGCOL 14
8.12
BGCOL 7
8.12
AT 832 −224 1184 −32
8.12
The PC version should read:
8.12
DEF FRAME “Thu,15 Jul 1993.14:16:55;2”
8.12
TEXT “text01”
8.12
STYLE “Jotter”
8.12
SIZE 480
8.12
HCENTRED
8.12
FGCOL 14
8.12
BGCOL 7
8.12
AT 832 −224 1184 −32
8.12
In WORD frames, you must delete the line beginning FONT completely.
8.12
To place your Genesis application into the Gen Apps directory on PC
disc, you can drag it over using RISC OS, restart Windows and your
application should be there − you don’t need to convert file types at
all. Having tried this a few times, it seems to work most of the time,
but I still have trouble making the PC recognise the new application.
Any thoughts, anyone?
8.12
The end bit
8.12
If you have any hints and tips or questions on multimedia or, if you
require a swap shop catalogue, please write to: Paul Hooper, 11 Rochford
Road, Martham, Great Yarmouth, NR29 4RL. (01493­748474) u
8.12
Networking Column
8.12
Chris Johnson
8.12
In a mad moment, shortly after reading the August (8.11) issue of
Archive, I contacted Paul and volunteered to act as editor of a new
column devoted to networking. Paul seized the offer of help with great
alacrity, and here I am. This first appearance of the column is simply
to draw readers’ attention to the fact that the column now exists, and
to seek contributions for inclusion in later issues. I see this column
covering all aspects of networking Acorn computers, i.e. when two or
more machines are linked together, with some sort of file or application
server. Most such networks will presumably be running part or all of the
Acorn AUN software.
8.12
Networking experience
8.12
Let me outline my own experience of networking Acorn computers in the
Chemistry Department of Heriot-Watt University, to set the ball rolling.
In later issues, I may amplify some of the issues, if I think them to be
of general interest.
8.12
We started with an isolated thin Ethernet system, using Acorn’s original
Level 4 Fileserver software. This proved to be very slow, little faster
than the old Econet system, and was very disappointing. We had purchased
Oak Solutions’ ClassNet cards, and when they announced their ClassShare
application server, we immediately upgraded the onboard ROMs. The
ClassShare application server was a great improvement for loading
applications − about an order of magnitude faster than Level 4 − and
this was used successfully for two years or more. The Level 4 Fileserver
was run in parallel (from the same server machine) to allow those that
wished to have their own private disc space on the network.
8.12
In recent months, the Internet and the Information Superhighway have
rarely been out of the news. It was time to get connected! This would
require us to use full IP addressing protocols on our network. The Oak
Solutions cards are easily reconfigured to be fully TCP/IP/AUN
compatible. Unfortunately, in the process, you lose the ClassShare
capability. However, all was not lost. Upgrading the Level 4 AUN
software to Release 3 brought us the Acorn Application Accelerator as
part of the suite. This does everything that the ClassShare software
did, is very fast and, as a bonus, allows more than one application
accelerator on the same network. This software was duly installed and
worked well.
8.12
Now it was really the time to get connected. We had two choices − either
use one of the Acorn computers as a gateway station, or use dedicated
hardware. In the event, the latter option appeared the more attractive.
We purchased from Atomwide a learning bridge, and a two-port repeater.
The Department’s thick Ethernet spine, linked via fibre optic cabling to
the campus LAN and thence to SuperJANET, was connected (via a
transceiver and AUI drop cable) to the bridge, the bridge was plugged
into the repeater, the second port of the repeater was connected to the
thin Ethernet segment, the repeater (which also powers the bridge) was
switched on, and bingo − we were on the Internet. (Plug and play? − Eat
your heart out!)
8.12
Acorn’s TCP/IP provides telnet and ftp capability. Downloading files
from, for example, the software archive at Lancaster University (Hensa)
is almost as fast as loading from a local hard disc and is very
impressive. Stewart Brodie’s ArcWeb gives us full access to the World
Wide Web − a fascinating way of browsing information, but also a huge
time waster as one wanders the world aimlessly from one link to another!
The amount of network traffic generated by graphics files is enormous.
Since the bridge is not hardware specific, we shall also be able to put
‘real’ PCs on the same segment of thin Ethernet (if absolutely
necessary), and Risc PC’s with PC cards should be able to talk to our
Novell servers (courtesy of Aleph One).
8.12
6 year-old server?
8.12
It might interest readers to learn that the fileserver machine is one of
our first A310s. It now has an ARM3, 4Mb RAM and an IDE hard disc. It is
running the Application Accelerator, the Level 4 Fileserver and the
!Spooler printer spooler to a PostScript laser printer, and copes very
well with all the loadings we have ever put on it. That’s not bad for a
six+ year old computer which has run essentially 24 hours a day, 7 days
a week, 52 weeks a year for the last four years!
8.12
Problems?
8.12
But wait − it’s not all sunshine and roses. When using full IP
addressing protocols, the Ethernet card cannot be booted from the
onboard software. Instead, the !Internet (from TCP/IP) and !Bootnet
(from AUN) software must be booted from hard disc before the Application
Accelerator is launched. This applies to all current AUN Ethernet cards,
whatever their source of manufacture. We still have several A3000s
without hard discs, for which a Catch22 situation exists. They need to
access the network to load the IP software, but cannot access the
network without the software. If anyone out there knows how to
circumvent this (other than booting from floppy disc), I should be very
pleased to hear about it. Otherwise, we have some A3000s, complete with
internal Ethernet card, going cheap − make me an offer someone!
8.12
How wide should we go?
8.12
Since my own networking horizons are now worldwide, I am not sure
whether any restrictions should be placed on the coverage in this
column. Should we be dealing only with local Acorn networks, or should
IP connection qualify as well? In the first instance, I am ready to
accept anything remotely connected with networks (no pun intended) −
comments, hints, tips, queries, problems (if solutions are provided to
the problems then so much the better). It will then be a case of seeing
how the column develops, based upon your feedback. (Chris, you will have
to negotiate with Adrian Bool, our Internet Column Editor, to see who
does what! He is [e-mail]. Ed.)
8.12
How to contact me
8.12
My address is Chris Johnson, 7 Lovedale Grove, Balerno, Edinburgh, EH14
7DR; I can also be contacted by e-mail as [e-mail]. u
8.12
Spreadsheet Column
8.12
Chris Johnson
8.12
I thought I would jog readers’ memories about this column. It does still
exist, just, but I need feedback and submissions to make it viable.
8.12
Eureka
8.12
The problem with the cropping of the toolbox on screen mode change,
which I mentioned in the last column, can be worked around. It requires
that you open the !Eureka application directory (by double-clicking with
<shift> held down). In it you will find a directory named Resources.
Open this directory. Load the file Settings into Edit or another text
editor (make a copy before making any changes). A few lines into the
file, you should find the lines
8.12
FullWidthControlPanel   = 1
8.12
MinimumWidthControlPanel= 0
8.12
Change the lines to read
8.12
FullWidthControlPanel   = 0
8.12
MinimumWidthControlPanel= 1
8.12
Save the new version of the file.
8.12
When Eureka is subsequently run, the tool bar produced corresponds to a
width of 640 pixels (e.g. mode 27). Thus the tool bar can never be
cropped on a mode change. It also has the advantage that, in larger
screen modes, you do not have to move the pointer all the way to the
right hand edge of the screen to toggle the tool bar.
8.12
So much for the good news. Now for a new problem. When font styles are
selected using the main menu option Format > Font... there is no
problem. Any installed font can be selected. Having been a regular user
of Eureka before the introduction of the button bar, this is the way I
normally make font style changes. However, there is also a button bar
option to change font style, but this works unpredictably. If the font
is a “standard” one, such as one of the RISC OS 3 fonts, the selection
works normally, but if you have a non-standard font, in many cases, the
selection of the font as a style does not work, and is ignored. Has
anyone found the answer? There is a file in the above-mentioned
resources directory named FontMap, which contains some font listings and
settings, but it is not clear how this file is used by Eureka, and I
have been loath to tinker with it. I would welcome comments on this
feature of Eureka.
8.12
How to contact me
8.12
My postal address is Chris Johnson, 7 Lovedale Grove, Balerno,
Edinburgh, EH14 7DR; I can also be contacted by e-mail as
[e-mail].
8.12
I am happy to receive anything in connection with spreadsheets, hints or
tips, macros, problems, solutions to problems, or just requests for
help. u
8.12
Help!!!!
8.12
Ancestry II − There seem to be problems with this new version, or am I
alone in having difficulty?
8.12
Roger Woolford, 3 Park Works Cottages, Nutfield, Surrey, RH1 4HG.
(01737-823519)
8.12
Bug reports − Dave Pantling has volunteered to be the Archive Roving Bug
Reporter! In other words, he thinks it would be a good idea to collate
known bugs and, if possible, work-arounds. I think it will involve him
in a lot of work but he seems keen to give it a go. So, if you know of
bugs or ‘features’ of any Acorn-related hardware and/or software, send
details to Dave, preferably on disc (800Kb, not 1.6Mb) to save him
retyping and, if you want a reply or your disc returned, please send him
an SAE. You will need to give clear details of what circumstances cause
the condition, how it manifests itself, complete details of your
hardware configuration, software title and version, supplier and other
software running at the time.
8.12
So, if you have ideas about this project (whether a private individual
or a software house!) send them to Dave along with your bug reports.
8.12
Dave Pantling, 31 Cornwall Grove, Bletchley, MK3 7HX.
8.12
Computer desk − Can anyone recommend a computer desk which looks smart
enough to blend in with (modern) living room furniture? Also, are there
any covers which fit the Risc PC 17“ monitor and keyboard and are made
of something better looking than the usual “plastic mac” material?
8.12
Peter Jennings, St Albans. (01727-861835)
8.12
DDE − I am having problems with an application downloaded from the
Internet. This is a program to sort sprites in a sprite file, and was
collected from Hensa. My son downloaded it using a PC and so it is on a
DOS 720Kb disc. If you click on the icon on that disc, the application,
which uses the Front End module from DDE, runs quite happily and does
the job for which it was intended. However, if I copy it to a RISC OS
disc, either hard, floppy or RAM, clicking on it produces an error
message saying that the wimpslot is not big enough to load the templates
and the program refuses to load. I have tried putting the wimpslot up to
1024Kb, but it still doesn’t make any difference.
8.12
David Wild, Hemel Hempstead.
8.12
Impression borders − I was fascinated by Cain Hunt’s tip about
‘Impression Borders’ in Archive 8.10 p14. I was thrilled to learn how
easy it is to produce borders of varying type and thickness. However, I
discovered that it is not possible to obtain curved or bevelled corners
at 3pt thickness and below. Has anyone else noticed this? There does not
seem to be an easy way around this problem. Does anyone have any ideas?
8.12
Noel Williams, Fort William.
8.12
Impression Junior wanted − Has anyone got a copy of Impression Junior
that they could let us have if we make a £10(ish!) donation to your
favourite charity, please? (We asked for this before but what we got was
one that had already been upgraded to a later version of Impression, and
so, legally, the original version should not have been sold. Oops!
Sorry, CC! Has anyone got a copy that has not been upgraded, please?
For, say, a £20 donation?)
8.12
Ed.
8.12
Laser Direct (again!) − Recently, I needed to use the ‘ŷ’ character (ALT
134). It appeared on the screen OK, but would not print on an LBP8 using
Laser Direct 2.61! However, it prints fine on the other printers I have
tried. Does anyone know why this happens, or what I can do to get around
the problem?
8.12
(I use 2.63 on an LBP8 and I managed to print out the ‘ŷ’ character, but
I had to cheat because Plantin, which I use for the body text in the
magazine, doesn’t have that character, so I have had to use Trinity for
that one character. Ed.)
8.12
Also, while printing multiple copies, or sometimes single copies, if I
ask the computer to do some intensive activity, such as opening a
directory on a floppy disc, the lower half of the page is not printed!
Is this due to some actions not being interruptible by Laser Direct when
more information needs to be sent?
8.12
(I think the two of us ought really to upgrade to the latest version,
4.03, which will cost us each £10 +VAT, but which will solve all sorts
of problems including, as pointed out by Jim Nottingham, the “squashed
line syndrome”. Ed.)
8.12
Robert Lytton, Leeds.
8.12
Pinboard problem − In order to have some of my regular programs
available whenever they are wanted, without using up the memory needed
to have them on the iconbar all the time, I have put them on the
pinboard, and then incorporated this into my !Boot file. One of these
programs is Impression Publisher, and I have found that, at first, it
takes on a slightly distorted form of the icon of the program
immediately before it in the list − and this persists until I move it on
the backdrop. It then picks up its proper icon. If Publisher is the
first item in the list, there is an error message during booting and the
tail end of the list doesn’t get done. Has anyone else come across this
problem and, if so, have you managed to solve it?
8.12
David Wild, Hemel Hempstead.
8.12
Printer character definitions − In the July Archive (8.10 p47), there
was an article, WYSIWYG for £-sign, concerned with the defining of
characters for the Epson LQ/SQ range of 24 pin printers. This jogged my
memory about an application I produced several years ago when I used an
LQ800. It allowed you to define characters for use in either draft or
NLQ mode for the printer, using a magnified Paint-like grid to set or
clear pixels. The program took care of all the calculations, checked for
adjacent pixels being set, etc. The definitions could be downloaded to
the printer immediately, saved to disc, or saved to a spool file that
could be downloaded to the printer at boot time. After a dig around, I
found the program on an old disc, and it runs on my Risc PC, so is fully
RISC OS 3.1+ compatible. Since it was written in about 1989, it does not
comply with the latest style guide but, if there is sufficient interest,
I could soon fix that! If anyone is interested in a copy of this
multitasking program, send me a disc and return postage. All disclaimers
apply, program is supplied as is. If I am flooded out with requests
(into double figures!), I may revise it and bring it up to full
standard.
8.12
Chris Johnson, 7 Lovedale Grove, Balerno, Edinburgh, EH14 7DR.
8.12
Risc-DOS Column − Simon Coulthurst has had to call it a day with editing
the Risc DOS Column and he’s even had to sell his computer −
commiserations, Simon, and thanks for all you have contributed to
Archive. Good luck for the future!
8.12
So, if that side of things is to continue, we need a new Editor. Any
offers? If so, your first query is from Charles Barraball, who wants a
Windows for Playgroups article − a sort of non-PCers survival guide. He
says that, “Those throw-away comments such as ‘running a DOS shell
within Windows’ are just so unintelligible to, presumably, many of your
readers − or is it just me?”
8.12
Mind you, I’m not keen to clog up Archive with info about PC things.
Surely, all this sort of thing is covered in the PC magazines, isn’t it?
(Thankfully, I don’t have to read them!) How about sending in
suggestions for books and articles that those who need to use PC stuff
can read? We need to confine Archive to those areas not covered
elsewhere, i.e. things relating specifically to using the PC cards and
emulators on the Acorn machines. Can anyone help, please?
8.12
Ed.
8.12
ProCAD − I am willing to swap ProCad files. At the moment, I can supply
kitchen units. Send me a formatted disc and an SAE.
8.12
Charles Barraball, 287 West Lane, New Malden, Surrey, KT3 6JE.
8.12
WIMP sprites − In last month’s Help column, Brian Cowan asked about
methods for ensuring only the first copy of a sprite is seen for
filetypes. The AddSprites utility on this month’s program disc does
this, and can also prevent the small icons loading if you never use the
full info, or small icon directory displays. Full details of its use are
on the disc.
8.12
Andrew Clover, Doggysoft. u
8.12
Programming Workshop
8.12
Colin Singleton
8.12
This column got off to an inauspicious start last month, because a
gremlin crept into my transfer of text to Paul. Every minus sign in the
Quicksort coding was mysteriously replaced by the letters ASC. The code
should have read:
8.12
Quicksort code
8.12
DEFPROCQuickSort(L$(),S%,N%)
8.12
LOCAL H%,L%,M%,F%,Z$
8.12
IF N%<2 THEN ENDPROC
8.12
F%=S%+N%−1
8.12
L%=S%−1
8.12
H%=F%
8.12
M%=S%+(F%−S%)DIV2
8.12
Z$=L$(M%)
8.12
L$(M%)=L$(H%)
8.12
REPEAT
8.12
  REPEAT
8.12
    L%+=1
8.12
  UNTIL L%=H% OR Z$<L$(L%)
8.12
  L$(H%)=L$(L%)
8.12
  WHILE L%<H% AND Z$<=L$(H%)
8.12
    H%−=1
8.12
  ENDWHILE
8.12
  L$(L%)=L$(H%)
8.12
UNTIL L%=H%
8.12
L$(L%)=Z$
8.12
IF L%>(S%+1) THEN PROCQuickSort(L$(),
8.12
 S%,L%−S%)
8.12
IF H%<(F%−1) THEN PROCQuickSort(L$(),
8.12
 H%+1,F%−H%)
8.12
ENDPROC
8.12
Date calculations
8.12
A frequent problem, particularly in commercial programming, involves
determining the day of the week of a given date, or producing a list of
dates at N-day intervals. This introduces the concept of Julian Date
which, contrary to popular opinion, has no connection with the old
Julian Calendar. The Julian date was named after Julius Scaliger, whose
son Joseph devised it in 1582.
8.12
Like all the best ideas, it is very simple. Instead of naming dates by
reference to a complex calendar, we number them continuously from an
arbitrary start date. Astronomers found it useful for cyclic phenomena,
and adopted a start date in 4713 BC. So, for them, October 25, 1995,
will be Julian Date 2,450,000.
8.12
To use the idea in software, we need to be able convert dates by program
between the Gregorian Calendar and the Julian Date, so that the latter
can be used for internal data processing. The coding given below uses
the base Julian Date 1 = 1st January 1 AD. A calendar date Day-Month-
Year (on the Gregorian Calendar) can be converted to Julian Date by the
following Basic function, or its equivalent in any other language. All
the variables are integers, but I have dropped the % symbols for clarity
− I hope!
8.12
Julian date
8.12
DEFFNJulian(D,M,Y)
8.12
IF M<3 THEN = D+((153*M+1379)DIV5)
8.12
+(1461*(Y−1)DIV4)−(3*(1+((Y−1)
8.12
DIV100))DIV4)−306
8.12
   :ELSE = D+((153*M−457)DIV5)+
8.12
(1461*Y DIV4)−(3*(1+(Y DIV100))DIV4)−306
8.12
In Acorn Basic, but not necessarily in other languages, we can combine
these two lines into a single function without an ‘IF’, by using (M<3)
as an arithmetic operation. If M is <3, this evaluates to −1, if not, it
evaluates to zero. The combined function is −
8.12
DEFFNJulian(D,M,Y)
8.12
=D+((M+9)MOD12*153+2)DIV5+(Y+(M<3))
8.12
*1461 DIV4−((Y+(M<3))
8.12
DIV100+1)*3 DIV4−306
8.12
Calculating the day of the week is now trivial. If J is the Julian Date,
J MOD 7 is the weekday (0 = Sunday ... 6 = Saturday). We also need to be
able to convert a Julian Date (J) back to the conventional Gregorian
Calendar date. This is most easily done using the following four lines
of Basic coding −
8.12
N = ((4*((4*J+1223)MOD146097 DIV4)+3)
8.12
MOD1461 DIV4)
8.12
D = 1+((5*N+2)MOD153 DIV5)
8.12
M = 1+((5*N+308)DIV153)MOD12
8.12
Y = 100*((4*J+1223)DIV146097)+
8.12
(4*(((4*J+1223)MOD146097 DIV4)+240)DIV1461)
8.12
The value N is an internal variable (it is in fact the number of days
since the last March 1st).
8.12
Easter
8.12
This month’s special offer! You won’t need this very often, but if you
do need to know the date of Easter in a given year it can be very
difficult to find out. The function given below works for the Gregorian
(present day) Calendar. Given the year, it returns the date in March of
Easter Day − if Easter is in fact in April, it returns a value greater
than 31. For example, FNEaster(1995) = 47. March 47th is April 16th.
8.12
DEFFNEaster(Y)
8.12
LOCAL G,C,E,A,W
8.12
G=Y MOD19
8.12
C=Y DIV100
8.12
Y=Y MOD100
8.12
E=(G*19+C−C DIV4−(C*8+13)DIV25+15)
8.12
MOD30
8.12
A=(G+E*11)DIV319
8.12
W=(C MOD4*2+Y DIV4*2−Y MOD4−E+A+32)
8.12
MOD7
8.12
=E−A+W+22
8.12
Comments please
8.12
I hope we have got rid of the bugs this month! Please send comments,
questions and suggestions to me at 41 St Quentin Drive, Sheffield, S17
4PN. u
8.12
Risc PC Column
8.12
Keith Hodge
8.12
A rather short column this month, I’m afraid, as I’m going off on
holiday and so my workload has gone through the roof!
8.12
Software information
8.12
Arthur Taylor has come up trumps again with a suitable 768×512 monitor
definition file for the AKF85, as requested last month. I have sent a
copy to Paul for inclusion on the monthly disc. Arthur also mentions
that he is currently working his way through the intricacies of MS-DOS
“CONFIG.SYS” and “AUTOEXEC.BAT” files and I am sure that there will be a
large amount of discussion about the configuration side of DOS / Windows
in the coming months.
8.12
Martyn Purdie has been having problems with his PC486. The bug is rather
obscure and only occurs if you place PC486 in the Tasks directory of
!Boot so that it is run when your machine starts up and is configured
with a setup such that DOS/Windows boots to single task mode when PC486
is run.
8.12
The problem which then manifests itself is that the hourglass turns on
during the boot sequence and stays on . This then leaves you with the
rather unusual phenomenon of a fully working Windows mouse pointer on
screen, which is closely followed at every move by an Acorn hourglass!
8.12
The solution is to add a line to the PC486 Run file. N.B. it must be
placed, as shown, in the run file, otherwise some strange errors occur −
as Martyn found to his frustration!
8.12
RUN ADFS::4.$.!BOOT.UTILS.HOFF.HOFF
8.12
WimpSlot -min 448k -max 640k
8.12
IconSprites <Diva$Dir>.!Sprites
8.12
|
8.12
|Run <Diva$Dir>.!RunImage > <Diva$Dir>.TraceFile
8.12
Run <Diva$Dir>.!RunImage
8.12
Software compatibility
8.12
If there is one thing that I would like to see introduced on the
Risc PC, it is a common database lookup feature which all software had
common access to. I now have three different database managers and files
on my machine! One is in ArcFax, one in Prophet and one Multistore. All
of these have almost common contents. Is it not possible for Acorn to
establish a system similar to that provided by Twain for scanners, so
that any application can have access to phone / fax number / address /
name, all from a common compliant database manager provided by the OS?
8.12
I have received a helpful letter from David Pilling, in which he says
that he has not come across the problem of the intermittent appearance
of black vertical lines on scanned images. Have any of my readers come
across this problem? I use a Canon I­4015 with Cumana SCSI 2 interface.
8.12
Hardware and software news
8.12
I have just been asked by Martyn Purdie if I have had any problems with
printing from DOS applications. My reply was that I do not use my 486
card to print − all I do is transfer files from the PC format file I
receive, across to FireWorkz for Windows, and then send the file to
FireWorkz on the Acorn platform, and then to printer via the Acorn
Printer Manager.
8.12
I have now tried to print direct from Write, the text editor provided
with Windows, but there is no printed output. Have any of you had
success and, if so, what settings are you using?
8.12
Tailpiece
8.12
As usual, I can be contacted by letter at the HES address on the back
page, by telephone after 7p.m., or by Packet Radio from anywhere in the
world, as GW4NEI@GB7OAR.#16.GBR.EU. u
8.12
Gerald’s Column
8.12
Gerald Fitton
8.12
My column is shorter than usual this month since our editor decided to
publish early! Although this month’s column has a statistical flavour, I
think that even those of you who are not statisticians will find parts
of it interesting.
8.12
Turbo Drivers etc
8.12
Let me tell you about the experience of Eddie Lord.
8.12
He wrote to Computer Concepts on 26th Feb 1995 complaining about his CC
Turbo Driver. He was having a series of problems with both his A540 and
a new Risc PC. The problems with the Risc PC were much worse than those
of the A540. His 26th Feb 1995 letter to CC finishes “I have written
about this before but not received a reply . . .”
8.12
The good news is that Eddie eventually received a reply in April
offering upgrades to Impression and the Turbo Driver. The bad news is
that these did not completely solve his problem. Eventually, he asked
for and obtained a free of charge replacement for his “old original”
dongle. In his letter to me dated 6th July 1995, he says “Apparently my
old original dongle was not bidirectional and could not cope with Turbo
Driver version 4... My version of Publisher is now v4.05 and the Turbo
Driver is 4.03”. The new dongle, together with the upgrades, has solved
his problems.
8.12
Now to Peter Boxall and his problems – they were similar to those of
Eddie.
8.12
After some correspondence with me he got in touch with CC and his last
letter to me includes the following: “I have to purchase v 4.03 of Turbo
Drivers (£10 +VAT)... As regards the bidirectional dongle... ...the
advice (is) that the one I have should be OK”. Peter concludes this part
of his letter to me with “Once I have installed the new Turbo Driver, I
will experiment”.
8.12
Printers v1.28c
8.12
I referred to these new Acorn printer drivers in last month’s column.
Since recommending them, I have had correspondence stating that things
go wrong with v 1.28c. Upon pressing my unhappy correspondents to
describe their problems in more detail, they have often been similar to
those reported by Eddie and Peter. My suggestion to these people was to
upgrade their copy of Publisher, to upgrade their Turbo Driver and to
try to get a replacement dongle from CC.
8.12
All those who have upgraded and obtained a replacement dongle are now
happy people!
8.12
If you are having difficulty with Printers v1.28c, use Publisher and use
Turbo Drivers, please don’t write to me for help until you’ve done the
same as Eddie! I am tempted to suggest that you write to Colin
Singleton, since he keeps asking me what I have against CC and pointing
out that their products give him no problems.
8.12
Let me say publicly to Colin that I have nothing against Impression,
indeed I am on record as saying that, for DTP, both Style and Publisher
are very good, I recommend them to you and Impression is my DTP of
choice. Some of you will know that I run a user group called ILine for
users of Style and Publisher. It is the fact that the package has so
many good features which leads to the viability of ILine. If nobody
bought Impression then ILine wouldn’t exist! My only complaint is that
interaction between some of CC’s products and other people’s products
does cause problems – and then people write to me (and not to Colin)!
8.12
Weighted averages
8.12
As far as I am aware, there is no spreadsheet in which there is a
formula for the calculation of weighted averages with the added feature
of ignoring blank slots.
8.12
I have to acknowledge that the inspiration for this next section of my
column is due to James Ducat who writes: “Help! I am an English teacher
trying to produce a mark sheet for my classes which is based around the
idea of a weighted average for each unit of work”.
8.12
James sent me a demonstration of what he has done towards solving this
problem. With slight modification, the file he sent me is shown in the
screenshot.
8.12
I guess that you’ll have noticed that James is using PipeDream. If you
have Fireworkz and not PipeDream, indeed if you have any spreadsheet
other than PipeDream, I’m sure that you’ll be able to make the
appropriate adjustments to the formulae I quote so that it suits your
spreadsheet.
8.12
Before taking the screenshot, I placed the cursor in slot F7 so that you
can see the formula used by James. Taking out the $ signs, used only
during the replication process, the formula reads:
8.12
((C4*C7)+(D4*D7)+(E4*E7))/sum(C$4E$4)
8.12
This is the classic definition of a weighted average.
8.12
Blank slots
8.12
A further quote from James is: “ ...when a child has been absent or not
handed in work... ...PipeDream is treating this as a zero mark, whereas
I really want it to ignore the blank cell”. In the screenshot, you will
see that the slot D7 is blank. What James wants is for the result in F7
to be 7.00 and not the 5.17 given by the formula.
8.12
If you have used PipeDream or Fireworkz for calculating ordinary (non-
weighted) averages of a range of slots, some of which are blank, you
will have discovered that the function avg(range) does not treat the
blank slots as zero but ignores them completely. Let me give you an
example using the spreadsheet shown in the screenshot. The average of
the range C7E7 calculated by avg(C7E7) will be 7.00; this is 14 divided
by 2 and not 14 divided by 3.
8.12
What we want is a function which ignores blank slots in the way that
avg() does, but which calculates the weighted average instead of the
non-weighted average.
8.12
Weighted average with blank slots
8.12
Have a look at the screenshot opposite.
8.12
Again I have placed the cursor in one of the crucial slots, I7, before
taking the screenshot, so that the formula is visible. It is:
8.12
if(D7=“”,“”,(D4*D7))
8.12
In the ‘Application of Number’ skill courses I teach at College, a
distinction is made between a formula expressed in symbols (as above)
and the same formula expressed in words. Using symbols is a higher level
skill. Indulge me whilst I practice converting the above formula into
words as: “If D7 is a blank slot then make I7 a blank slot, otherwise
make I7 = D4*D7”.
8.12
Understanding the formula in K7 is important to following why this
application works. It is:
8.12
if(C7=“”,0,C4)+if(D7=“”,0,D4)+if(E7=
8.12
“”,0,E4)
8.12
and gives the value 17. This 17 is made up of the 7 in C4 and the 10 in
E4. The 6 in D4 is replaced with the value 0 because D7 is blank.
8.12
The average calculated in slot L7 ignores the blank slots. The formula
it contains is:
8.12
sum(H7J7)/K7
8.12
and gives the value (49+0+70)/17 = 7.00.
8.12
This is the weighted average ignoring blank slots which James requires.
8.12
What is a ‘median’?
8.12
James also wants a formula for the median of each of the columns of
data.
8.12
When dealing with highly skewed (lopsided) distributions such as the
distribution of wages, you can easily be misled if you concentrate only
on the mean. One way of avoiding being misled is to think of the median
instead. The median wage is a wage such that half the wage earners earn
more and half earn less than the median wage. I notice that the media
now refer to the median wage (much lower than the mean) and Labour
politicians talk in terms of a proposed minimum wage which is some
proportion not of the mean but of the median wage.
8.12
So that you can appreciate the advantage of using the median instead of
the mean, let me relate (in much shortened form) one of the many
anecdotes I tell my statistics students and which, like all my best
stories, is almost true!
8.12
Some years ago, when much younger, my son, David, talked his way into a
salesman’s job. He was taken on a three month trial under the following
conditions. “Start at £3,000 a year and, if you do well, I’ll raise your
salary to at least the same as the other sales staff.” David asked what
the average salary was and was told it was £10,000 p.a. (This was a long
time ago when £10,000 was a lot of money.)
8.12
He did well and ‘won’ a set of (cheap) cuff links as ‘Salesman of the
Month’ in his third month. He was looking forward to at least the
monthly equivalent of £10,000 p.a. and was amazed to receive only half
the amount he expected.
8.12
After an argument, he was told that the £10,000 ‘average’ for the
company consisted of nine salesmen (including David) on £5,000 p.a. and
the ‘boss’ on £55,000 p.a.! So much for arithmetic means! The median
wage for that company was £5,000. David should have asked not about the
mean salary, £10,000, but about the median salary, £5,000.
8.12
A second, even shorter example: About ten years ago when inflation was
in double figures, nurses had a pay rise which averaged 18% (true) but
80% of nurses received less than an 8% rise (also true)! The median wage
rise was around 6%. A few on high wages received wage rises of 25% or
so, pulling up the mean to 18%!
8.12
Finding the median
8.12
PipeDream does not have a built-in function to calculate the median of a
set of data. No problem! Just write a custom function called ‘median’!
One of the lovely things about well-written custom functions is that you
don’t have to understand their inner workings to use them. Over the
years, I have accumulated a wide range of custom functions provided by
correspondents. I haven’t looked at the inner workings of some of those,
like ‘median’, which I use the most!
8.12
Back in early 1992, a contributor who shall remain anonymous (at least
so far as this column is concerned) sent me a custom function which I
have used on many occasions to calculate the median of a range of
values. Inspired by James, I studied its inner workings for the first
time last week – now I’ve improved it so that it ignores blank slots.
8.12
The modified function is on the Archive monthly disc. It is:
8.12
....function(“median”,“list:array”)
8.12
\ return the median value from an
8.12
 unsorted list
8.12
\ sort the list
8.12
...[c_sort]sort(@list)
8.12
\ define and initialise ‘local’
8.12
 variables
8.12
...set_name(“arow”,B9)
8.12
...set_value(arow,rows(A6))
8.12
\ delete blank slots
8.12
...repeat
8.12
...if(index(A6,1,arow)=“”,set_value
8.12
(arow,arow−1),)
8.12
...until(index(A6,1,arow)>“”)
8.12
\ if odd number of items, find the
8.12
 middle one
8.12
...if(mod(arow,2)=1,result(index(A6
8.12
,1,(arow+1)/2)),)
8.12
\ if even number of items, find
8.12
 middle two and split the difference
8.12
...index(A6,1,arow/2)
8.12
...index(A6,1,arow/2+1)
8.12
...result((A20+A21)/2)
8.12
The word ‘median’ on the first row is the name of the function. The
‘list:array’ is a parameter passed to the custom function and is the
unsorted array.
8.12
In the custom function the slot A6 is the slot containing
....[c_sort]sort(@list). After ‘sort’ has done its work, the slot A6
contains the sorted version of the array. I am not going to include a
textual version of ‘sort’ in this column; it is on the monthly disc and
consists of a simple sort routine containing a couple of nested
for – next loops.
8.12
At the bottom of the sorted array, you will find all the blank slots –
if there are any. I have defined a local variable ‘arow’. Initially, the
value of ‘arow’ is the number of rows in the sorted array. The
repeat – until loop which follows the heading ‘\ delete blank slots’
reduces the value of ‘arow’ until ‘arow’ is the number of items in the
sorted array which are not blank.
8.12
The median of a sorted list is the middle one. The remaining rows of the
custom function find the value of the middle item. If the number of
items in the list is even then the median is considered to lie half way
between the two middle values.
8.12
James would also like a custom function which calculates the two
quartiles. The upper quartile is a value such that 25% of the set of
data is larger than the upper quartile. The lower quartile is defined in
a similar way. Those of you in teaching contemporary uses of statistics
will know that there is a great deal of interest at the moment in the
10% of households that are either at the top or bottom of the sorted
list! Perhaps you’ll be able to modify the custom function so that it
calculates these percentiles. Anyway, if you do improve the custom
function, please let me know and send me a disc copy so that I can make
it more easily available to others such as James.
8.12
The Lottery
8.12
I knew that this item would generate much interest. I have had many
letters about the statistics, philosophy and morality of gambling,
together with many amusing and some distressing anecdotes. One piece of
philosophy which is repeated in many of my letters is “Be careful what
you wish for – it may come true!” I’m sorry but most will have to wait
for another day – but please keep writing. I’ve selected just one piece
of correspondence; files relating to it are on the Archive monthly disc.
8.12
Donald Bindon has sent me 32 weeks of lottery results, together with an
analysis of frequencies using the Poisson distribution. I reckon that
the true distribution must be Binomial (with n = 32) but a Poisson
distribution is a good approximation; the approximation improves as the
weeks go by and n gets larger. His submission includes an interesting
custom function which, almost as a throw away item, includes an
insertion sort routine which I would like to include in my ‘median’
calculations! His custom function also uses the deref() function in
conjunction with index(,,) in a way which I find most interesting. I’m
sorry I don’t have time to go into detail, perhaps another day – anyway
you’ll find it on the monthly disc.
8.12
Donald reports that: “An article in The Times newspaper of Saturday
28th Jan 1995, reported that a chi-square analysis of 12 years of the
results of the Australian National Lotto had concluded that they were
far from truly random. Anyone wanting to improve their chances of
winning could do so by following the trends”.
8.12
I can’t believe it! I would prefer to believe that something has gone
wrong with the statistical analysis. Over the years, I have had many
contributors who have sent me chi-square custom functions both for
PipeDream and for Fireworkz. I am always interested in receiving
alternative versions. If you have one which analyses Donald’s data (or,
if you’re one of my many antipodean correspondents, the Australian
National Lotto results) then let’s have it!
8.12
Finally
8.12
Thanks for your many letters. Please continue to send them to the Abacus
Training address (not to Archive) which you’ll find at the back of
Archive. u
8.12
Video Matters
8.12
Ned Abell
8.12
With the run-up to the Autumn show and with the introduction of a new
generation of Risc PCs, software and hardware manufacturers are starting
to create a queue of interesting video-related products. I have a few
details for you, but first a review of a product that is available
now...
8.12
AlphaLock
8.12
I’ve been waiting for some months now for the latest Millipede offering,
having drooled over the prototype of their new genlock card at an Acorn
World show a couple of years ago. That was to work on the Archimedes,
but then along came the Risc PC and Millipede realised that if they were
going to produce a flagship product, they would have to conform to the
new computer.
8.12
My AlphaLock arrived in a small box, beautifully packed and as soon as I
opened the lid I could see the quality. It consists of two complete
expansion cards in one, so it’s going to populate a whole slice of a
Risc PC. You need 2Mb of VRAM to run it too, so this is not a cheap
addition to a video suite. Mind you, it is built to PAL broadcast spec −
and it looks it.
8.12
You will also probably need to upgrade the RAM, depending on software,
so this whole exercise needs deep pockets, especially if you need a
second slice of case. Along with the boards come a well printed manual
and a disc of software to calibrate and demonstrate aspects of the
board.
8.12
It does...
8.12
A genlock allows you to mix computer graphics with incoming video and
output this to a video device. The genlock can be used in two ways. In
the upstream mode, it works as a source of computer generated graphics
which are then mixed with other sources through a downstream video mixer
to caption, etc. In the downstream mode, the video source from recorder
or camcorder or vision mixer is fed into the AlphaLock which is used as
an additional video mixer to overlay the computer graphics onto the
video.
8.12
The AlphaLock is software reprogrammable and, indeed, a few days after
receiving it, along came a newer manual and a disc which overwrote the
operating software on the board. It’s possible this software upgrade
service will be offered to certain customers at a later date by e­mail!
The board will accept input and output from composite (ordinary) video
as well as Y/C, that’s S-VHS to you and me.
8.12
Soon, another board called AlphaLock Studio will be on offer that offers
Y/R-Y/B-Y component for those lucky Betacam suite operators. An NTSC/PAL
version is also promised. There is also a Genlock input to lock the
board upstream in a studio and software is provided to lock to this
source as well as configuring to more jittery sources such as a tape
player. A Key output can be used to control a downstream mixer and the
software can be programmed to provide a delay. You can also route the
computer monitor via the board.
8.12
Popping in the slice...
8.12
The installation should have been straightforward, but it was installing
the second slice that was my problem as the computer power supply had to
be changed. In doing this, I disturbed the hard disc controller and the
machine didn’t boot. The AlphaLock itself went in easily, only needing a
small lead attached to a plug (PL5 by the VIDC20) on the motherboard.
8.12
Once my computer’s boots were straightened, I went on to explore the
software. This is very simple at the moment as applications are still
being developed for the board. Current software will allow the AlphaLock
to be configured in upstream or downstream mode, to generate colour bars
and to generate a simple caption sequence. The first decision is
where in the video suite will it go and I decided for downstream
operation as I want primarily to caption over video. The AlignUS and
AlignDS programs take care of this and are run as soon as the video
cables are connected up. With a colour source running into the genlock,
I was able very accurately to software-control the video phase and
timing using a mouse button and key presses. This is very impressive.
8.12
Once set − forget! It’s remembered for you because all the parameters
are stored, with the software, in the flash memory. Then the calibrate
program was set up and this automatically sets the video output to be
correct because the incoming RGB signals from the Risc PC can vary
between computers. Again, these values are stored in the flash memory
and can be reset if you move the board to another computer.
8.12
Display
8.12
Having got the system up and running, I then moved on to trying some
sequences and used the supplied demos to show overlay, fade and pixel
contrast reduction over a video source. What’s so good about the
AlphaLock is that it lets you vary the intensity of the computer pixel
compared with the incoming video, so you can fade in and out of captions
in software on the AlphaLock itself, and also reduce the intensity of a
block, so that you can make those captions where you can see what’s
going on behind the caption block. It’s ideal for subtitling.
8.12
Alpha channel
8.12
This intensity control is called Alpha channel and so it’s possible to
define the colour coming off the computer as red, green, blue and alpha
and this alpha gives sixteen different intensities for the computer
image, background image and key level. Using a lookup table in the
software, the intensity can be made to become 256 levels so the
different effects that are capable of being generated are huge. But is
the software there to support the AlphaLock?
8.12
Well, development boards have gone to a number of software houses and,
for example, CableNews2 is being expanded to provide this alpha channel
control. The software on the board, of course, can be reprogrammed to
take into account third party software development, so this is extremely
future­proof.
8.12
Modes
8.12
Because AlphaLock is providing a video signal, it has to have special
modes and can only show these modes so, in many cases, they won’t appear
on the standard Risc PC monitor − but, of course, the output will be on
the video monitor. Provisional modes supported are:
8.12
Mode  bits/pixel  resolution  interlace
8.12
Double height pixels
8.12
100  1  768×288  repeat
8.12
101  2  “  ”
8.12
102  4  “  ”
8.12
103  8  “  ”
8.12
104  16  “  ”
8.12
105  32  “  ”
8.12
Square pixels
8.12
106  1  768×576  fully
8.12
107  2  “  ”
8.12
108  4  “  ”
8.12
109  8  “  ”
8.12
110  16  “  ”
8.12
111  32  “  ”
8.12
You can see why this beastie needs 2Mb of VRAM! Indeed, in fully
interlaced modes, this is all used up. The manual does make the point
that some applications may not work properly in fully interlaced modes
and Millipede will supply details to authors of applications who wish to
modify them. Note the double height and square pixels used.
8.12
Acorn haven’t fully explained how alpha channels will work, so as
Millipede are interpreting and implementing, my advice to software
writers is to get in touch with them to provide a uniform standard. The
manual details many of the ways in which to use the alpha channel and
provides tips, such as how anti-aliased fonts should always be anti-
aliased over a black background, as the AlphaLock will then use that
information to provide a degree of transparency when the video is added.
If you are a programmer, note that all of the * calls and SWIs are
included in the manual.
8.12
Conclusion
8.12
The wait was well worthwhile and, although expensive, this product will
last and is upgradable. If you have anything to do with professional
video captions or video graphics on a Risc PC, you shouldn’t buy
anything else. Millipede’s support is also first class − I received an
unsolicited phone call checking the board had arrived and whether it
installed OK. They are also a company that’s been around a long time −
they used to make genlocks for the BBC Model B − so they have a good
track record. The Millipede board is a great leap forward in that it
provides a significant resource for the computer, provides a vision of
how to use software to cope with the adaptability of the platform, and
also has the ability to change as operating systems change by ‘re-
flashing’ the board.
8.12
Using the AlphaLock
8.12
CableNews2 will soon be providing Millipede support and the Video
Utilities also written by Paul Reuvers, are also now almost ready for
the Risc PC. The video timeclock and leader caption program are being
worked on.
8.12
Clares have received a board and are considering support with “Titler”.
Oregan Developments are also beavering away and CineWorks will support
Millipede, too. I’m told that Oregan will also be making a hardware add-
on to CineWorks to accept timecode so that video, captions and sound,
etc, within the application, can ‘Rock’n Roll’ with external pictures.
So, with a combination of packages, things are really looking up. Now
all we need is AudioWorks Professional or a similar audio editing
package, along the lines of SADiE, plus, of course, ISDN support, so the
resultant files can be whizzed around the world!
8.12
Video mutterings
8.12
Now back to other matters concerning video... One area that’s generated
some correspondence is multimedia boards like the CC’s Eagle M2 and
Irlam’s 24i16. It seems that a lot of people don’t realise that you
can’t digitise to obtain VHS standard video out of them. Well you can,
almost, but your pictures are very much dependent on compression
techniques, computer memory processor and hard disc speed.
8.12
What they do very well is to grab a whole frame to 24-bit standard as a
sprite, as well as digitise audio. They also digitise moving video to
Replay file standards, but this isn’t always full frame or 25 frames per
second. This won’t always be the case because the compression algorithms
are getting better and hardware is evolving to cope with the speed
required to shuffle all this data.
8.12
With a Risc PC 600, you can’t affordably grab your favourite camcorder
moments, edit them, add captions and sound effects, and replay to
another tape at full frame with little or no picture degradation − not
yet − but the introduction of Risc PC 700s does bring the possibility a
little closer.
8.12
There is another element in the equation that’s creeping up on us and
that is standards. VHS is in most homes worldwide and S-VHS hasn’t
really taken off because of cost, but there is a new contender available
soon − digital VHS, or D-VHS. Broadcast camera manufacturers are
starting to offer digital cameras for news, where you shoot the pictures
and sound onto a camera with removable hard disc, pull out the disc and
digitally edit in a van on your way back to base and transmit the story.
It won’t be too long before your home camcorder will be able to do a
similar job.
8.12
Panasonic have seen the light and will be offering the next generation
of VHS machine at the end of the year that stores information on a
digital VHS tape and plays back S-VHS and VHS and records as well. It
therefore shouldn’t be too much of a leap to provide in-camera D-VHS.
Also, it will have an interface enabling it to accept all sorts of
digital data in different formats, so you could probably copy a CD,
archive PhotoCD etc, or store downloaded internet pages or an MPEG
movie. The exact way in which it will do this is unclear but it will
certainly have implications for archiving computer data from hard disc.
8.12
The AlphaLock is £775 +VAT from Millipede Electronic Graphics. I can be
contacted via Archive or on 100341,[e-mail]. u
8.12
Language Column
8.12
David Wild
8.12
Because I try to keep up to date, I have been having a look at C++, in
both Acorn and Beebug versions. Many of the criticisms that I have made
of C in the past have been answered, and it would seem that quite a
number of useful features of Pascal have been brought in. I particularly
like the stream method of input and output, as this gets rid of the need
to think of the actual variable type at the time you are writing the
output statements.
8.12
It often seemed to me that, as in a number of places, some of the
compiler’s work had been delegated to the programmer, with a
corresponding increase in the risk of silly errors. In the PC field,
some of the compiler writers had compounded the problem by generating
different code for statements which should have had the same effect
according to the rules of C. (One review of a compiler in an American
magazine mentioned that you must use var+=1 rather than var=var+1 if you
wanted the most efficient code. To my mind, the abbreviated forms should
be redundant, which is not the same as saying that they should be
abolished, just as e.g. and i.e. are in written English.)
8.12
The Beebug version of C++ is not documented but seems to work correctly
in general. There were a few errors in the first release, notably with
the instream method of input for floats, but they were corrected in
later releases. The documentation for the Acorn version is much more
substantial, but there are no worked examples or real example programs.
All you get is two versions of “Hello World”, one of them with a fairly
obvious bug. A silly problem with the original release was that instream
input needed <ctrl-D> to terminate it instead of just <return>. There
was no mention of this in the documentation, but it has been corrected
with the update which is available from Internet or can be bought, for
£5, from Vector Marketing.
8.12
Because I didn’t know the language, I thought that I had better read
something about it so I looked on the shelves in the bookshops. In spite
of the title, “C++ for Dummies” seems to be an excellent book which
explains how the various features work and why they are there. The
author is prepared to admit that some of the features are not
particularly vital, while being enthusiastic about the ones that are.
8.12
I also bought “Teach yourself C++ programming in 21 days” from Sams
Publishing. It is an absolutely fascinating book, because it has not
been proof read at all. There are programs from which you are asked to
remove the bugs, when there are none, and others which are supposed to
work but contain bugs. All the listings have line numbers against them,
but in some cases comments have been added to the listing since the
explanations were written − so the explanation doesn’t tie up with what
you see. There are numerous other mistakes, the worst one being that the
software which generated the text has replaced two consecutive minus
signs by an en-dash. This is especially unfortunate in a book devoted to
a C-derived language and makes a big hurdle for a beginner. The silly
thing is that, if you know enough about the language to recognise the
mistakes, the author has had some very good ideas and gives some
excellent explanations of what is going on. The book, though, is
supposed to be for the absolute beginner and must confuse someone who
has never programmed before. If a program doesn’t work, it will be
difficult to work out whether you have made a mistake or the book itself
is wrong. It is a great shame that such a potentially good book should
have been spoiled by lack of care. u
8.12
Mice
8.12
Richard Torrens
8.12
This is a tale of rodents and Risc PCs as well as mice and older
Archies, for I now have a new Risc PC. As supplied, the Risc PC mouse is
completely interchangeable with the older creatures, so if you are
thinking of getting a new pet, read on.
8.12
My trusty old Archimedes 410/1 has been upgraded and used heavily. It
eats rodents − it is now on its third mouse. Also, I use the mouse so
heavily at times that the older Acorn mice were a pain − quite
literally, for I developed a sore spot at the base of one finger where
it rested on the old mouse.
8.12
Also, I had other troubles with mice. They are dirty creatures − mine
kept on getting a dirty ball, causing the wheels to stick. Also, the
ball tended to slip. I had effected a partial solution by dismantling
the mouse and packing it so that the ball retaining spring applied more
downward pressure but this was only a partial cure. What I wanted was a
nice new mouse with a nice comfortable feel and, if you will pardon me
saying so, some lead in its ball, for a weighty mouse ball is the secret
of a good, slip-free existence.
8.12
Alternative mice?
8.12
I looked at all the Archimedes mice I could find. I was unimpressed. Too
angular, too light in the spherical component. So I started looking at
IBM mice. Mostly, these are serial mice, quite unsuitable for Acorn use
(except, of course, with the Risc PC). But there are so called ‘Bus’
mice available with the correct 9-pin connectors and these can be
modified for Acorn use. But I was wary at first, as no one seemed to be
able to tell me the IBM connections. In the end, I found this out from a
local dealer.
8.12
So I duly purchased a Logitech Mouseman deluxe Bus mouse. This is
ergonomicly shaped and has a weighty sphere. Gone are the old sore
spots! The mouse is very light to use on the buttons: it has taken me
quite a time to avoid accidental button presses because the buttons
respond to the slightest pressure − they are, in fact, over-sensitive.
The ball doesn’t retain rubbish either. Unfortunately, it does still
pick up rubbish which it duly deposits on the pressure rollers inside
so, after some time of use, it develops a distinctly ‘gritty’ feel. Time
to clean out the mouse, a task all keepers of small rodents seem to have
to put up with. However, the ball has never seized up or slipped from
being dirty.
8.12
The instructions which follow refer to this Logitech mouse, but should
apply to other similar mice with a 9-pin mini DIN plug.
8.12
Mouse physiology
8.12
How do they work? Inside the mouse are two wheels, each one similar to
the drawing overleaf. The wheel is usually made of black plastic with
rectangular slots punched in it. I have shown slots at 60° spacing but
they are usually closer. Shining through the slots are two LEDs (Light
Emitting Diodes). Each LED shines onto a light sensitive transistor. The
two emitters are spaced so that, when one transistor can ‘see’ its LED
through the centre of its window, the other LED is looking at an edge
and is therefore switching on or off.
8.12
In my illustration, the LEDs are spaced at 105° (60° × 1.75). The output
voltage from the transistor is processed to switch rapidly from high to
low as the LED’s light is transmitted or occluded so that the voltage is
low when the transistor is lit and high when it is in darkness. In the
diagram, LED 1 is fully illuminated and LED 2 is switching. Note that
LED 2 may be switching from light to dark or from dark to light − this
depends on the rotation direction.
8.12
Now consider the second drawing. Here the wheel is shown in four
different states, each rotated 15° from the previous one. Diagram E is
equivalent to diagram A, being 60° rotated. For clockwise rotation, the
states follow each other in order A-B-C-D-E from left to right but if
you read the states from right to left, E-D-C-B-A, then these correspond
to anticlockwise rotation.
8.12
Notice that LED 2 is changing state from light to dark in diagram A for
clockwise rotation and in diagram C for anticlockwise rotation. So if we
measure LED 1 every time LED 2 goes from light to dark, if LED 1 is
light then we are rotating clockwise but if LED 1 is dark, then we have
anticlockwise rotation. The computer uses this fact to monitor
direction: each time LED 2 goes from light to dark it samples LED 1 to
determine the direction. It uses the number of transitions to measure
the distance.
8.12
In practice, the system is a little bit more clever, since there are
problems if the wheel stops on an edge. Of course, the two LEDs are
interchangeable, and it doesn’t matter which one is used as the step and
which as the direction. If, in re-wiring, you get the two signals
interchanged, the mouse will simply work upside down or left to right
instead of right to left. The diagram below shows the corresponding
electrical signals switching at 15° intervals.
8.12
There are two such wheels, one rotates for vertical movement and the
other rotates for horizontal movement of the mouse ball. If you take
your mouse to pieces, you can easily see these two ‘encoders’ as they
are called. The actual wheels have a lot more slots than I have shown.
8.12
The Logitech mouse
8.12
The diagram below shows the inside of the logitech mouse with the
connections as supplied for IBM use and as required by Acorn.
8.12
The Mouse’s tail terminates in a crimp connector which mates with pins
on the circuit board. It is necessary to disengage each crimp from the
plastic housing.The engaging mechanism varies with different makes of
connector. Sometimes, there is a tine on the metal contact, sometimes a
tine on the housing which locks onto the contact. With a pin, you can
usually depress the locking tine and gently pull the terminal out. Don’t
use too much pressure or you will bend the tine. If your mouse has a
different colour scheme or pin order to the Logitech, you will have to
get out an ohmmeter and check the continuity of each wire through to its
pin. Make a ‘before and after’ chart as above so you know what the wire
connections are, and which pin they connect to, so you can rearrange
them in the correct order. If your mouse has the correct 9-pin mini DIN
connector and three buttons, you should be able to convert it quite
simply.
8.12
And finally...
8.12
As a complete change of subject, this article, plus all the drawings,
was going to be sent to Paul via ArcFax (some few moons ago) which he
also uses. But he thought there were too many complications, so I did
not send it and it lay dormouse (sorry, dormant) until I received a
request for an article. A shame that − because it really is very quick
and easy to send files by ArcFax. Perhaps he’ll awake now and make the
facility available to everyone (hint).
8.12
OK, I can take a hint! Next article you send, Richard − you let me know
and we’ll see if we can make history! Or we could just try it anyway,
see if it works, and then you could write an article about how it was
done. OK? (To be fair, the reason it was complicated was that I use the
bulletin board line as an out-going fax line. When the BBS was
operative, it would contend with ArcFax for the privilege of answering
the phone. But now that the BBS is no more...) Ed. u
8.12
RISC OS and Windows − Part 2
8.12
Keith Parker
8.12
New machines and OS
8.12
I was pleased to learn that Acorn has launched some new machines −
namely the Risc PC 700 and the A7000 − at competitive prices! I also
found out that a new (updated) version of our favourite operating system
is onboard − RISC OS 3.6. I am not claiming that my wish list had any
bearing on Acorn’s move but it is good to see that some of my wish list
is being incorporated, namely:
8.12
New Filecore: This will allow us to address up to 4Gb of hard disc
storage. (16Gb on SCSI.)
8.12
New Paint: This will allow 24bit files to be created and edited.
8.12
Additionally, the new prices look very attractive, especially compared
to the new lower priced Apple PowerMacs − Well done, Acorn!
8.12
RISC OS 4 − More ideas
8.12
Since my last article, I have received some more ideas for RISC OS 4 −
now I do not want to put our Clan Acorn columnists out of business, so
may I suggest all further comments or ideas go to them (via Paul, if
needs be!). Having said that, these ideas are so good and apply to my
main sphere of interest, DTP. So I will detail them here:
8.12
i) LongFileNames: This is not new but something that needs to be
addressed with a major degree of urgency. I know there are some PD
programs that allow this feature but surely the Acorn programmers can
match Apple and MicroSoft − after all, they have led them so far!
8.12
ii) CMYK: The implementation of CMYK (cyan, magenta, yellow and black)
in Draw leaves a lot to be desired. Perhaps Acorn can look at this at
the same time as acquiring the rights to the Pantone library.
8.12
iii) Colour Balance for Monitors: Most monitors and computers used in
the professional markets have the ability to balance the colours and
calibrate the displays more accurately. This is, I suggest, a major job
so it may need to wait for RISC OS 5 (?).
8.12
iv) Save into directories: We need the ability to drop and save a file
into an unopened directory.
8.12
v) Alt-tab (Windows) shortcut (pt 2): I mentioned this last month, but
have since found that it allows the user to rotate through applications
without needing to keep going back to the directory display or the
iconbar.
8.12
vi) Save from within an application: When pressing <f3> in Windows, you
get a dialogue box that allows you to specify exactly where you want to
save your work. This is especially important where you have a screen
full of open windows.
8.12
CorelDraw3 CD
8.12
I received a call from a reader who was having problems converting .cdr
files (CorelDraw’s native format) to ArtWorks. For anybody else who is
experiencing these problems, or who is considering buying CorelDraw for
the clipart, here is the process involved.
8.12
1) Fire up Windows and insert CD in drive.
8.12
2) Double click on Main Folder then File Manager and select drive D (or
whatever letter you have allocated to your CD drive).
8.12
3) Open up the clipart directory and double-click on the *.cdr file you
want.
8.12
4) After waking up and seeing the CorelDraw loading banner for the
umpteenth time, click on FILE, and halfway down is the option EXPORT.
8.12
5) Click on EXPORT − this opens a dialogue box.
8.12
6) Select Illustrator 88, 1.1 and 3.0, as these seem to be the versions
that are most widely understood and stable. Also ensure that the drive
window shows c: (if your CD is drive D and the box shows d:, change it
or you get an error message).
8.12
When you have done all that, click on OK! A new box opens up:
8.12
7) I suggest that you save as v3.0 and ensure that, if your chosen file
contains text, Text as Curves is on. Illustrator EPS files with strange
font information can do strange things to ArtWorks.
8.12
8) Another box entitled ‘CorelDraw is Exporting’ opens up with a dial
telling you how much has been done.
8.12
9) When complete, quit the PC card and double-click on your drive C (in
the RISC OS “PC” directory).
8.12
10) Double-click on the Corel30 directory and you should find a file
entitled */AI. (As Windows allows longer names than RISC OS, if any part
of /AI is missing, ArtWorks will NOT load it.)
8.12
DTP packages − Is size important?
8.12
I was offered the Serif Publishing Suite on CD­ROM at the ridiculous
price of £9.95 +VAT (manuals extra) so I bought it. Quite a nice package
but the size of disc space required is awesome. Serif PagePlus v3.0
needs 10,072,991 bytes against Impression Publisher’s 3,511,820 bytes
(including WordWorks and Equasor). Tony Tolver (of T-J fame) supports
PagePlus and wrote an article for the PagePlus User Group’s magazine −
not in PagePlus but in Impression Publisher Plus!
8.12
Excellent quality publications produced on Acorns
8.12
I was asked by another reader if there were any other magazines (of
“professional” standard) that are produced using Acorns apart from Land
Mobile. The one that immediately sprang to my mind was Acorn Publisher.
8.12
This magazine is coming to the end of its first year of publication and
should be considered essential reading by anyone who aspires to using
their Acorn for DTP. It was created by that stalwart of the Acorn world,
Mike Williams − best known as editor of Risc User and as a contributor
to many different Acorn publications. This ambitious project uses Acorns
(from start to finish) to create a magazine that aims (and succeeds) to
appeal to beginners and experts alike. It contains news, reviews, hints
and tips, master classes and case studies of Acorns in the publishing
world. Articles are written by people who, in many cases, use Acorns for
their living, like Walter Briggs, past CC ArtWorks winner, Richard
Lambley, editor of Land Mobile and our own Mark Howe, editor of the DTP
column. If you want to get more out of your Acorn in dtp then get your
hands on Acorn Publisher − it is nearly as good value as the Non-
Designer’s Design Book! (We have now sold over 300 copies of NDDB,
offering complete money-back guarantee − and only one has come back!
Ed.)
8.12
Sample copies are available from Akalat Publishing, as well as a twelve
month subscription (six issues). Sample copies cost £4.50 (UK), £5.00
(Europe) and £6.00 (rest of the world), post paid to your home.
Subscriptions cost £24.95 (UK) and £34.95 (overseas).
8.12
Printers 1.28c
8.12
Following the last issue of Archive, I decided to upgrade to Acorn
Printers v1.28c. This is available from Archive for £5. Before you
complain, as previous upgrades only cost £2, if you purchase it direct
from Acorn it is £10! It seems to be much more stable and to provide
much better colour results and some new PDF’s.
8.12
One problem I have discovered occurs if you load Printers first and then
load Publisher − the Publisher loading banner goes transparent, apart
from the text that states “Licensed to …  ” and the outline border to
the banner. This does not occur if you load Publisher before Printers.
What is interesting is that it does not affect Publisher Plus! Any
ideas?
8.12
DTP Comparisons
8.12
My plans are for the following articles:
8.12
Article One: Impression Publisher Plus and OvationPro compared with
QuarkXpress (Mac).
8.12
Article Two: Impression Publisher Plus compared with QuarkXpress (PC),
PageMaker5, Corel Ventura and PagePlus3.
8.12
Article Three: OvationPro compared with QuarkXpress (PC), PageMaker5,
Corel Ventura and PagePlus3.
8.12
Article Four: “The Showdown” − Impression Publisher Plus versus
OvationPro.
8.12
Obviously, the timescale for Articles One, Three and Four depend on
Beebug, i.e. when OvationPro is launched. We all know that this vast
project is late (as was Impression Publisher) but neither of these
projects are, or will be, as late as that programming saga, Windows4,
Windows95, or whatever it is now called.
8.12
If anybody has any comments or ideas on what they would specifically
like to see in these comparisons, please do not hesitate to contact me.
8.12
Keith Parker, 33 Fieldend, Twickenham, Middlesex, TW1 4TG. (0860-919-
216) u
8.12
MacroLife
8.12
Chris Whitworth
8.12
MacroLife is a desktop version of the ‘Game of Life’. No, were not
talking about that silly board game with the annoying clicky wheel in
the middle. We’re talking Cellular Automata − well, we couldn’t call it
anything simple, could we? People might think they understood it, and
that would put scientists out of a job. For those who’ve never heard of
it before, the ‘game’ goes something like this: You have a big grid −
the life plane − within which there are a load of cells, some ‘alive’,
some ‘dead’. A rule is then applied to every location on the grid, and
the next generation calculated using the rule. The rule is then re-
applied, and so on.
8.12
The standard game follows the rules laid out by John Conway in 1970.
These dictate that a cell will be alive (ie. it will exist) in the next
generation if it has three living neighbours in the current generation.
If it has two neighbours, it stays as it is. If it has any other number,
it will be dead. Each cell has eight neighbours (up, down, left, right
and four diagonal).
8.12
What do you get?
8.12
MacroLife itself is available in two versions − the Freeware ‘demo’
version (which I believe appeared on the July Acorn User cover disc),
and the Careware ‘full’ version. This basically means that if you buy
the full program from the author, he’ll donate some money to Motivation
− a charity who provide wheelchairs for people in developing countries.
The demo is identical in almost every respect to the full version,
except when you first run the demo version, a window pops up encouraging
you to register.
8.12
What you get for your money is a single disc and a well-written manual,
covered with what looks suspiciously like cling-film. The software is
not copy-protected, and can be installed on a hard disc. However, each
copy has a licence name and number encoded within it, so any pirate
copies can be tracked down to the original source.
8.12
In use
8.12
Double-clicking on the application results in it installing itself on
your iconbar, and clicking on this icon presents you with a blank life
plane (as shown overleaf), with a toolbar along the top. It is now you
begin to realise what an amazing piece of coding this actually is − the
life plane itself is 65536 by 65536 cells in size − a quick calculation
tells us that this is over 4 billion cells. Now, even only using 1 bit
per cell, this would theoretically take up 512Mb(!) of memory, which my
A3000 hasn’t got. There’s obviously some clever coding going on
somewhere...
8.12
There are several ways of investigating life from here − you can either
insert one of the predefined patterns into the plane, and watch this
develop, or design your own. The supplied patterns are very impressive −
particularly the Microchip (see below). However, it is much more fun
designing your own patterns, and letting them grow. You can either draw
them freehand, cell by cell, or by using the ‘drawing tools’ − which
consist of filled rectangles, move and copy options, rotation and
flipping options, and a random pattern generator.
8.12
Once you’ve drawn your pattern, you can set it generating. There are
several options for this, too. You can run it in ‘real time’, step by
step, to a specific generation, at several speeds, or any combination of
the above. The generation is fully multitasking (although a faster
single tasking option is available), and it is fast − even on my ARM2
A3000. On a Risc PC at full speed, it is often impossible to make out
exactly what is going on, it runs so fast!
8.12
Options
8.12
So far, what I have described just sounds like every other Life program
available in the public domain (apart from the speed). However, what
really sets it apart from the rest of the crowd are its customisation
options: besides the ‘standard’ game of life − known as Conway’s life −
there are also several other versions implemented, and even a feature
which allows you to create your own rules. By adjusting the rules
slightly, you can create some amazing and intricate patterns.
8.12
Other options include: the ability to zoom the life plane to a variety
of (oddly chosen) sizes; to save the whole plane, or just single
objects; local, regional and global overview windows; to centre the view
on the origin of the plane; to change the cell colours; to wrap around
at the edge; to turn auto-scrolling on and off; to turn toolbar help on
and off; to have a wide or narrow toolbar; and to turn the grid on or
off.
8.12
The program is very easy to use and, in case you are in doubt as to what
the tool icons do, you can turn the help text on, which gives details of
the button the mouse pointer is over. The only criticism I have here is
that, to access the grid clear/reset functions, you have to double click
on another, completely unrelated, icon. However, once you’ve got used to
it, it actually works very well.
8.12
Conclusion
8.12
I have only really scratched the surface of this incredible program in
this review − there is so much more to it than can possibly be explained
in a single article. The only way you can get to know is to try it for
yourself. I would have no hesitation in recommending this to anyone who
is remotely interested in cellular automata − it’s fast, it’s big, it’s
incredibly user friendly, it’s got more options than a Ford Escort, and
the profits go to charity. What more could you ask for?
8.12
Sending a cheque for £8 to Chris Taylor at 32 Burghley Court, Great
Holm, Milton Keynes, MK8 9EL. (01908-569556) u
8.12
I tried it out too, and I have to say that it is a quite amazing piece
of software. I only wish I had time to play with it! I also happen to
know that Motivation is a good cause, so go for it. Ed.
8.12
JPEG in Action
8.12
Stuart Bell
8.12
For well over a year, I edited the Archive JPEG column, comparing
various JPEG applications, and providing a commentary on the increasing
use of JPEG techniques on RISC OS machines, to the point at which they
were so well established that I felt that a regular JPEG column was no
longer necessary. (JPEG stands for Joint Photographic Experts’ Group,
and is a machine-independent technique for reducing the disc space
needed to store large bit-map images. See Archive 6.9 – “First Steps
with JPEG” – and subsequent issues with the JPEG Columns, for more
information.)
8.12
However, during that period, I never needed to use JPEG for a large-
scale project! The aim of this article is to pass on the lessons learned
in a major application of JPEG compression.
8.12
Slide-tape or disc-tape?
8.12
The project started as a slide-tape programme, with an audio commentary
and soundtrack accompanying perhaps three hundred 35mm slides. Very
soon, I realised that using computer-based images (albeit with the sound
sourced from audio tape) would give greater flexibility in the use of
images, and make far simpler the production of captions, multiple images
and special effects. Anyway, it would be much more fun! Final video
output would be to a VCR, via a PAL encoder, and the audio would be
added later, dubbed onto the video tape. (I know that the sound could
also be done on the computer, but I wasn’t confident in my ability to
locate and use a package which would allow for 20 minutes of continuous
audio, whilst images are changing every few seconds.)
8.12
The next problem was to identify the software to assemble and sequence
the images. I tried Quickshow from Desktop Projects, which at £10 was
brilliant value, but rather limited. I modified it to run in mode 21
(rather than just mode 15) but was still left with images that would not
fill the full width of the screen. To modify the package to run in the
wide mode 35 (or similar wide versions of mode 21) would have needed a
major re-write, which I hadn’t the time (or the inclination) to attempt.
Jim Nottingham kindly sent me a demo version of CableNews, but – as he
warned me to expect – it had an unnerving propensity to crash, not just
itself, but the whole machine. Later versions are probably more robust,
but they’re not cheap. Hence, I used Genesis Project. It works quite
well, but I have felt that, on occasions, I was fighting its ‘stripped-
down-ness’ when compared with Genesis Professional, and it isn’t as
robust as, say, Impression Publisher. Its use as an automatic ‘slide-
show’ sequencer could take a whole article in itself – and probably
will, when the project is complete.
8.12
Scanning services
8.12
Unless you use a digital camera – increasingly available, but still
expensive, especially at decent resolutions – then the first stage in
producing such an A/V project is to get the images onto disc. As I’d
already purchased the slide film, my photographs would be on that
medium, while to them I would add photos from magazines and guides
(copyright permitting). This is where JPEG comes in.
8.12
I first approached Birdtech (33 Blackbird Close, Bradwell, Gt. Yarmouth,
Norfolk, NR31 8RT), who is an Acorn dealer, but also offers a scanning
service. There, Roy Robinson was very helpful. The trial slides I sent
for scanning weren’t wonderful, but the demo print scans he sent back
were very good. I used Birdtech for all my non-slide scans, and received
a very prompt and economical service. Some of the very large scans of A4
pictures were superb, and simply couldn’t have fitted on a 800Kb disc
without the use of JPEG.
8.12
For slides, I turned to Bluebell Software (PO Box 2923, Witham, Essex,
CM8 2SQ) who offer a very comprehensive scanning service, and also stock
related software, aimed mainly at PC users. Hence, they supply images on
PC-format discs, but that’s no problem to Acorn machines. Bluebell send
a 60­page catalogue to prospective customers with lots of sensible
advice about image scanning, and it was this that confirmed JPEG as the
ideal file format for my images. They use a Nikon film scanner, not a
transparency attachment to a flat-bed scanner, and the superb results
show the quality possible with a device that goes up to 2700dpi!
8.12
Lesson 1: Use a scanning service with a proper film scanner for best
results with slides.
8.12
Bluebell also gave me excellent service, with their “Rapidscan Level II”
640×420 pixel images at 75p a time. That may not sound very high
resolution, but it’s quite adequate for screen displays. Bluebell are
very keen advocates of JPEG image compression, and the booklet stresses
its advantages. Certainly, despite it being clear from a ‘phone
conversation that Bluebell would hardly know an Acorn from a hazelnut, I
had no problem at all with the JPEG images they produced from the slide
which I sent to them.
8.12
Lesson 2: JPEG cross-platform portability is a reality.
8.12
It was soon after I started planning the project that the Risc PC was
announced. Its 24-bit colour capability would have been nice (although
you’d be surprised how good 256 colour images can look) but I knew that
I simply couldn’t afford one before the project is due for completion.
However, what of the future? Might I want to re-master the project with
16M colours in the future? Quite possibly. One thing that I under-
stressed in the JPEG Column, perhaps because it wasn’t so relevant at
the time, was that JPEG images are 24-bit images (provided, of course,
that the scans are made at 24 bits per pixel!) At the moment, I can’t
access all those lovely colours on my A310, but as long as I keep those
images safe, some day I will. . .
8.12
Lesson 3: JPEG images are future-proof.
8.12
For safety’s sake
8.12
And so, as the photographs were taken, processed, and despatched to
Birdtech and Bluebell, the discs of images started to arrive. The 197
slide images currently run to 19Mb, and those from 42 photographs amount
to a further 11Mb. The sprites produced from them total 46Mb (which
would be 132Mb with true-colour images). Whilst it could be argued that
the JPEG images which arrived on floppy discs don’t need backing up, no
such arguments could be made for the sprite files, which have not simply
been converted from the files, but cropped and, in many cases, edited to
clean-up the images. And these are ‘mode 35’ images – true colour high-
resolution sprites would run to 264Mb. (250 24-bit images at 800×600
would total 360Mb!)
8.12
It soon became clear that backing-up to floppy disc – which is possible,
if laborious, for text, Impression files, and a few images – becomes
quite impracticable for serious image-intensive projects. I bought a
105Mb Syquest drive from NCS and, especially with ClicBack, it’s
excellent. When the project is complete, all the files will reside on
one Syquest cartridge (or two with a back-up) and will not need to
clutter up my hard disc. The 270Mb units are even nicer, but whilst
their nominal cost per Mb is lower, if you want to store less than 100Mb
for one particular project on a cartridge, the cost per Mb of data
stored becomes greater. But, whatever system you use, you can’t sensibly
use floppies to back up such huge amounts of data.
8.12
Lesson 4: A hard disc back-up device is essential for protecting the
work in a major A/V project.
8.12
Image processing
8.12
The images arrived at my A310 as JPEG files; 640×420 for the slides, and
up to 772×1114 for the photographs. I eventually decided upon a 768×256
display for the image sequence, the former giving a full-width
‘overscan’ image and the latter giving small black margins top and
bottom, whilst the aspect ratio (3:2) is the same as for 35mm slides.
What software should I use for the conversion and editing? Towards the
end of writing the JPEG column, I’d found that recent versions (I use
0.95) of the ChangeFSI utility supplied by Acorn are as quick as any
other “de-JPEGing” software I’ve encountered, and further tests showed
that the quality of the images produced is as good as any others, as
well. It also has a wide range of processing and scaling facilities. So,
ChangeFSI was used for the JPEG-sprite conversion, slightly sharpening
and scaling the images in the process.
8.12
As far as editing the sprites was concerned, colour consistency between
slide-originated images was very good, and most of the photos were of
paintings, so I didn’t need to alter the colours. Cropping and touching-
up (eg to remove telephone wires from images) were all that was
required. I ransacked a PD library for possible software, ploughed
through endless badly-written (or quite inadequate) manuals, fiddled
interminably to accommodate astronomic memory requirements, went mad
watching the hour-glass tick away as images were laboriously processed
(and this with an ARM3!), and ended up using Paint!
8.12
With Paint, cropping is trivial, once you learn to use ‘Flip’ and
‘adjust size’ rather than ‘delete’ rows and columns, and the ‘use sprite
as brush’ made the eradication of cables from skies quite simple.
Paint’s simple air-brush and ‘set/clear pixels’ proved quite adequate to
complete the required tasks. I wished I’d tried Paint in the first
place, although I recognise that for 24-bit images something more
powerful – and expensive – may well be needed.
8.12
Lesson 5: Free software like ChangeFSI and Paint is adequate for most
simple image work.
8.12
Conclusion
8.12
As I write this, the project nears completion. It’s still in Genesis
format, but I may upgrade to Genesis Professional in order to produce a
more polished final result. Similarly, the latest PAL encoders with a
800×600 display facility – like that from Pineapple – may, in the long
term, allow a move to higher resolution images. And it might just be
that I’ll wait for a Risc PC before completing the project, to get 24-
bit images. In the long-term, it might be more economic to use print
film and buy my own flat-bed scanner, but that’s another story.
8.12
Whatever happens, my investment in JPEG images, sourced from non-Acorn
scanners, and backed up, if only for peace of mind, is safe. My
experiences have proved the importance and value of the JPEG image
compression and storage system for the continually developing
relationship of computers and still photographic images. u
8.12
Pocket Book Column
8.12
Audrey Laski
8.12
Power Pack Blues forever?
8.12
I still haven’t resolved the Power Pack problems I have been muttering
about for the last three columns, and the Pocket Book itself is now
under investigation. I am again in that state of frustrated deprivation
that comes from being without one’s treasured memory amplifier.
8.12
Pocket Book pouch
8.12
Richard Derby, of Welwyn, Herts. writes about a leather pouch designed
for the Psion 3a but, of course, equally useful for the Pocket Book. He
had suffered from the tendency of palmtops to treat trouser pockets as a
form of Colditz and try to escape whenever sitting down made it
possible, and he needed his Pocket Book II with him all the time because
of its phone power.
8.12
The only case that seemed available initially cost £25 and didn’t really
fill the need, but then a friend recommended the S3 Sleeve Case, from
Systemslink Two Ltd, Incon House, 10 Stilebrook Road, Olney, Bucks. MK46
5LL (01234-711220). This is “a padded leather pouch with a belt loop”,
costing £13.95. He says, “I have been using this pouch for four months
now and find it ideal. With such ready accessibility, I am beginning to
use more Pocket Book facilities.” He has noted that a similar pouch,
from Network Solutions, was described in Products Available, Archive
8.8, but observes that it is slightly cheaper from Systemslink Two,
which may be the manufacturer. I’m thinking of getting one myself, but
not, of course, till my hospitalised Pocket Book returns.
8.12
Still more about the A-Link
8.12
Richard also takes up some issues from earlier columns about the A-Link.
He notes that “there is no difference between the PC-Link except in the
wiring of the cable from the plastic sausage to the serial port of the
computer... The consequence of this is that PC-Links will only work with
IBM compatibles whereas A-Links will work with both Acorns and IBMs − at
least mine does!” He further confirms that Pocket Book II will, as
Julian Midgely surmised, transfer data at 19200, though he warns that
this option is only recommended for use with the A5000 or later
machines, because of the nature of the serial port of the earlier
Archimedes.
8.12
Endnote
8.12
Only one correspondent this month. Perhaps a flood of letters will come
in just after I have posted this to Paul. Perhaps I shall recover from
the Power Pack blues. Perhaps a computer manufacturer will put out a new
product at the deadline originally specified. Perhaps a herd of Old
Norfolk Spotted pigs will be seen flying in perfect formation over
Norwich...  u
8.12
Fire & Ice
8.12
Chris Coe
8.12
When I first played Fire & Ice, I felt there was a certain 16-bit
flavour about it. That’s not to say that it isn’t any good. It’s a
platform game − which is good news, because it’s quite a while since a
good platform game was released for Acorn machines.
8.12
The story so far...
8.12
Suten, having used his powers over the elemental forces (fire, water
etc.) destroys an entire solar system, and is condemned, by ‘the powers
that be’, to a life in prison. Not content with this new way of life, he
escapes and travels 12 lights years to Earth. So taken is he by the
place, that he decides he’ll stay, and take it over. Meanwhile... Glemm,
a kind of intergalactic Mounty, has picked up his trail and is
determined to take him back. Unfortunately, Glemm can’t materialise on
Earth, because that would alert Suten to his presence, causing another
stellar catastrophe. Instead, he uses an agent − not a human, of course,
they’re too stupid! Instead he chooses one ‘Cool Coyote’, the hero of
the piece. CC doesn’t know that he’s an agent for justice, so sets out
on this adventure unaware that he is a pawn in a deadly game of pursuit.
8.12
Playing the game
8.12
The concept is simple − hop, skip and jump around lots of levels,
blasting baddies and collecting parts of a key which will enable you to
escape... to another level! The game is split into countries, each
country being split into a maximum of five lands. To progress from one
place to another, you’ll need to accumulate six key sections.
Unfortunately, there does not appear to be any way of skipping lands
that you’ve already completed, forcing you to play through the whole
game every time.
8.12
Actual gameplay is good. To eliminate a baddy, you have to put it in the
deep freeze, with a liberal sprinkling of ice pellets. At this point,
jumping onto it will cause it to shatter, perhaps releasing a bonus, or
one of those vital key segments. You can get additional help from any
‘puppies’ that might be hanging around in the vicinity, who will follow
you around and shoot when you do. They won’t leap across great chasms
though, so their use is limited. Another great feature is that the
levels are all literally oozing with secret blocks, platforms, rooms and
bonuses, where you can pick up extra weapons, lives and so on.
8.12
The graphics are reasonably good, although the title screen and ‘Game
Over’ sequences could have been spiced up a bit. Sound effects and music
are sufficient and, thankfully, you can switch them off.
8.12
There are a few annoying omissions. There are no in-game pause or quit
buttons, although returning to the desktop is no problem. The omission
of a level skip or password system is rather frustrating, especially
since each level is fairly large. Overall, an above average platform
game that’s definitely worth a look at £24 through Archive. u
8.12
Comment Column
8.12
Acorn’s low depreciation − I have come to understand an important aspect
of buying computer hardware: depreciation. I have a six year old A410/1
worth £400. If it were a PC, it would be scrap by now. Why?
8.12
Firstly, ARM processor based machines seem to have a longer shelf life.
They are, generally, more easily upgradeable − this is nothing unique.
They are also very compatible but you won’t understand the real
significance of that unless you’ve tried to run Windows on an 80286 or
earlier. So what is the result of this future-proofing?
8.12
Acorn machines lose value more slowly than any other machines that I
have come across. An average machine loses about 20% of its value per
year, the machines still have a market and people still want to buy five
year old machines. (Who would want a five year old DOS machine?!)
8.12
(Or how about the ten year old BBC Bs that Ray Maidstone is refurbishing
for charity? We can’t get enough to fulfil the demand! Ed.)
8.12
If you want to buy a new machine every time one is released, every two
or three years, you only need to find a few hundred pounds on top of
what your previous machine would fetch. If we all did this, it would
increase the availability of secondhand machines, reducing their prices
slightly, but it would also increase Acorn’s sales, maybe reducing their
prices too.
8.12
If you have a PC-owning friend who comes to visit and is impressed by
your A5000, why not sell it to them and buy a Risc PC? This way, we
expand the user base, i.e. Acorn’s customer base, and ensure Acorn’s
survival.
8.12
Dave Pantling, Bletchley
8.12
C++ books − I can recommend very strongly an absolutely excellent book
on C++: ‘Developing C++ Software’, Second Edition (maybe it is in its
third edition by now...), by Russell Winder, 1993. It is published by
Wiley, ISBN 0 471 93610 3. It takes a very rigorous, but gentle,
approach and introduces the fundamental principles as required. It is
definitely not a ‘hacker-style’ book, but would make a first rate
introduction for anyone interested in C++.
8.12
A good second book would be Stroustrup (The C++ Programming Language),
or Coplien (Advanced C++) for those interested in complex programming
techniques. (Coplien is NOT for the faint-hearted!)
8.12
Michael Ben-Gershon, [e-mail].
8.12
Creepy Crawlies/Living World − The Archive price list mentions that
Creepy Crawlies and Dictionary of the Living World will not work on the
Risc PC. New driver s/w is available on the Acorn ftp server, and I can
attest that it works well!
8.12
Michael Ben-Gershon, [e-mail].
8.12
Escom − Remember Amigas? Well, it looks like they’re coming back and,
from what I’ve heard, it could be very bad news for Acorn. The ‘low end’
machine comes with a 33MHz 68030 processor, either 2Mb or 4Mb of RAM, a
hard disc of indeterminate size, and the capability of running three
operating systems − Amiga DOS, Mac OS and DOS. Apparently it’s going to
be less than £300. Now, the operating systems will probably be software
emulated, and the sub-£300 model will probably only have a small hard
disc and 2Mb RAM, but with the hype surrounding it, and with the Amiga’s
established reputation within the home, Acorn stands no chance against
this new foe. Sub-£300 Risc PC anyone? I think not, somehow.
8.12
Chris Whitworth, Wreningham, Norfolk.
8.12
PCs versus Acorns − In order to show why Acorns are preferable to PCs,
we need to explain the difference between the price of a product and the
cost of a product. The price of the product is the amount you paid for
the particular system and software needed to do a specific job.
8.12
The cost of the product is the overall monies you have to pay out to
keep it capable and up-to-date over a period of time.
8.12
Let me illustrate this by looking at two systems, one an Acorn Risc PC
and the other an IBM compatible, both for DTP users.
8.12
(Keith’s figures were for a 9Mb/420Mb ACB45 but I have updated his
figures in the light of the new machines and, not surprisingly, the
comparison is even better for Acorn − more capable for less money. Ed.)
8.12
The Acorn:
8.12
Risc PC700 10Mb/850Mb − 17“  £1943
8.12
Impression Publisher  £299
8.12
Studio24  £169
8.12
Scanner  £550
8.12
3 year on-site maintenance  £116
8.12
TOTAL  £3077
8.12
(Actually, you could use a 5Mb/420Mb ACB70 upgraded to 9Mb at £1728 −
i.e. £214 better still. Ed)
8.12
The PC:
8.12
486DX4, 8Mb/420Mb  £999
8.12
17“ Monitor  250
8.12
PageMaker v5  495
8.12
PhotoShop v3  385
8.12
Scanner  400
8.12
3 year on-site maintenance  125
8.12
TOTAL   £2654
8.12
So, at first sight, the PC is cheaper by about £423. However, to keep
the PC up-to-date you can expect two upgrades to PageMaker at about £150
each and two upgrades to PhotoShop again, £150 each. Windows eats memory
so it will need an upgrade, say £300, and the programs are huge, so
another hard disc, say £120. So even though the price was £2654, its
cost would become £3674 without taking into account the cost of paying
for support to run the software.
8.12
What about the cost of the Acorn system? Well, we know that upgrades
cost much less − remember that CC charged only £29 to upgrade to
Publisher from Impression2 − so (I hope I’m right) assume two upgrades
from CC at, say, £50 each. Pineapple say upgrades for Studio24 will be
free! So the software upgrades cost £100. (Even if CC abandon the Acorn
market, we move to Ovation Pro at £169 with two upgrades at £50 − the
cost will only be £269). These programs will run on 8Mb, so no
additional memory there, and the programs and files are much smaller, so
no additional hard disc. So, after a price of £3077, the cost becomes
(at most) £3346.
8.12
The PC advantage in price of £423 has become a cost disadvantage of
£328. Makes one think!!!
8.12
(Using an ACB70, that would have read... price advantage £209 and cost
disadvantage £542. Ed.)
8.12
Keith Parker, London
8.12
PC service? − Some time ago, Paul asked how Acorn dealers compare with
PC dealers as regards after-sales service. He may be interested to know
that, in the PCW awards, a couple of months ago, Watford Electronics won
second prize in one of the awards for best PC dealer. That may give some
indication of the relative merits.
8.12
Dave Floyd, London NW10.
8.12
PCs = games − I am a loyal Acorn user and have argued until I am blue in
the face with my workmates about how archaic and steam-driven Windows in
all its forms is. But the public sees IBM as a standard and what the
public sees, the public gets. They associate IBM, PC and Windows all in
one big WordPerfect-using-Doom-playing mass. And that is the crux of the
matter. People don’t want the ease of use of Acorn machines for serious
use. They want lots of games so that when they get bored after a couple
of weeks, there is a new game to buy. Most people profess to be buying a
machine for word processing and home accounts but all end up playing
games. I can say with certainty that ALL of my workmates have gone for
IBM-compatibles, mostly because they use WordPerfect at work and can
thus take work home but, more importantly, because all the others at
work have so many games that they can ‘borrow’ before buying their own.
8.12
What am I trying to say here? Microsoft in all its forms will rule the
world until the end of silicon as we know it. Every new leap or step
that computing takes will still keep it sufficiently close to the
previous level that Microsoft will be able to ‘cuff’ its current suite
of software to be able to hook people on to its new wares in whatever
new area computing has reached. All that Apple and Acorn can hope to do
is go with it. Once a user has committed to a system, they will not
change − they will constantly bodge on more and more bits to keep up
with changes.
8.12
How can we keep up with this? We live in a fantasy world if we think
Acorn will not get swallowed up into the ‘PC’ milieu. The 486 co-
processor on the Risc PC is the first step of the rot. The next will be
a main processor, based on a Pentium, or something similar. We will see
an increase in articles on using ‘PC’ suites on Risc PCs and a decrease
in Acorn-specific software; that is where the battle has been lost. I
boast about my A310 still being as powerful as a 486 but all my friends
need to say is “Can you play Doom? Does it have Civilisation or
Transport Tycoon?” 90% of users are entertainment-driven and want the
latest shiny thing now, not in 18 months to 2 years.
8.12
I hate being this negative, especially as my job teaches me always to
finish with constructive criticism. Luckily, I think that there is a
solution. Acorn must bring out a hardware upgrade for the Risc PC that
suckers people into buying it, thinking they are getting a Super-
Pentium. It must run ‘PC’ software with more ease than current ‘PC’s.
Then when people are busy playing Doom and Civilisation straight from
the Desktop and not having to re-rig their Soundblaster cards for every
different game, they can be shown how much better an Acorn machine is
for grown-up use. The battleground for market-share is not serious
computing − it is quite simply games. Games get people hooked.
8.12
Gavin Dobson, RAF Aldergrove
8.12
Sibelius playback problems − Further to John VEG Mitchell’s request for
being able to play two staves together, it is possible in a roundabout
sort of way. The two (or more) parts can be extracted together and then
played. The parts are extracted by selecting the appropriate instruments
by using <adjust> and then the ‘Edit->Extract part’ option. Don’t forget
to save the score before extracting the parts, which must be reloaded
after the extracted parts have been played.
8.12
Ian Beswick, Manchester
8.12
Strategy games − I am a big fan of strategy games and am disappointed
that there are not more of these for Acorn machines. The Acorn games
market seems to be dominated by driving games and shoot-’em-ups or
platform games for kids. A few that seem to have taken the PC world by
storm are Civilisation (easily the best strategy game ever), Railway
Tycoon, Transport Tycoon, The Perfect General and Fields of Glory. Are
there any signs of these coming out for Acorns?
8.12
Gavin Dobson, RAF Aldergrove.
8.12
StrongARM news − No, sorry, this isn’t the latest news about these
amazing new chips, it’s a plea for someone to go out there
(electronically speaking) and get some info about them and write it up
for Archive. There was an article in Acorn User but some people felt
that it was, at best, pessimistic. Would anyone like to try talking
nicely to the PR people at ARM Ltd to see if you can get something worth
publishing? (Ask me first though − we don’t want twenty Archive
subscribers all asking ARM Ltd the same questions!)
8.12
Ed.
8.12
TRUK − Talk Radio UK − Every Monday night on Talk Radio UK, between 10
and 11pm, Caesar the Geezer presents his ‘CaesarTECH’ programme, where
he gives details of all the latest technology, and ‘advises’ people on
what computers to buy for what needs. Or so he claims. What this
actually seems to be is an attempt to push every other computer
manufacturer apart from PC manufacturers out of the market.
8.12
If it were normal PC advocacy, it would be bad enough, but a few weeks
ago, a woman called up asking about what machine she should buy for her
six year old son, who wanted one he could use for his school work, and
also for educational applications. She just managed to mention that he
used ‘something called a BBC/Arc or something at school’ when Caesar
jumped in saying ‘Oh, it’ll be a PC compatible. Buy him a 286 and then
upgrade it to a 486 at a later date.’
8.12
How can we promote Acorn as a credible computer manufacturer when there
are ignorant (or simply completely biased) people in a position of such
power, telling people not to even consider anything other than a PC?
(His is the most listened to evening show, and the most popular phone-in
show in the country, with an audience of about 12 million!)
8.12
Chris Whitworth, Wreningham, Norfolk.
8.12
Twain in parallel − I have just bought an Epson 8500 flat bed scanner
for use on my A5000. David Pilling has recently adapted the Twain Driver
to work via the parallel port. Unfortunately, it will not work with
Computer Concepts dongles and Turbo Driver cable, so you will need to
unplug cables whenever you need to swap between scanning and printing.
8.12
Stephen Wright, Stanmore.
8.12
Word Imperfect − I too have to use WordPerfect (version 5.1 for DOS) at
work, and as a regular Impression Publisher user, I find it very
frustrating. However, I must confess that I could not do my work in
Publisher, because of the lack of certain facilities for technical
writing. I recently wrote a 97 page design specification in WordPerfect,
which used a 5-level, automatically numbered paragraph structure and
made extensive use of cross-references.
8.12
Just for the record, the only way I could complete the document was to
run WP on my Risc PC, under the Software Emulator (no 486 cards left!)
because my aging PC at work ran too slowly with such a large document.
Even on my Risc PC it took about 20 minutes to ‘Generate’ the document,
which included compiling the contents pages and working out the cross-
references. (I simply didn’t have the time to wait for an index!)
8.12
I too have purchased the Impression loader/saver, but wasn’t
particularly impressed with what it made of the files I exported to it.
There were so many embedded codes in the document that WP crashed at
regular intervals. Come on CC, give us the proper facilities in
Impression, rather than forcing us to resort to using the ‘industry
standard’ WP!
8.12
Ian Beswick, Manchester
8.12
Hints and Tips
8.12
‘Bad compression field’ − We have had a number of comments on the
subject of the Bad compression field error produced by Laser Direct and
the TurboDrivers, so many thanks to everyone who wrote in − too many to
mention you all.
8.12
The main causes seem to be either a lack of memory, or a lack of disc
space. The usual memory saving techniques apply, quitting unused
applications, reducing the screen resolution or number of colours and so
on. Lack of disc space is most frequent on floppy-only machines for
obvious reasons. During printing, a file is placed in the !Scrap
directory, so to ensure that you have as much space as possible, create
a scrap disc (preferably 1.6Mb if your computer will support it),
containing only the !Scrap application, and make sure that you double
click on that version before attempting to print. This will require
additional disc swapping, but should allow printing to continue
successfully.
8.12
NCS.
8.12
Booting problems − When exchanging the 80Mb hard drives in our two
A5000s for 430Mb drives, I reset the machine to auto boot, and had the
desktop auto boot option set, but do you think it would boot? The
solution was to issue a *OPT 4,2 command, from which point everything
behaved as anticipated. There were no discernible differences on
*STATUS.
8.12
This is a known bug in RISC OS 3. When you tick the auto boot option,
this should be set, but unfortunately it is not. The reason it makes no
difference to the status is that it is not a configuration option, but,
in fact, it writes the option to the disc. (If you do a *CAT then the
top line should read something like  Dir. SCSI:: Words.$ Option 00
(Off); the option given will be the second number in the *OPT command.)
MH.
8.12
Alan Jackson, Oamaru, NZ.
8.12
‘Formatting’ hard discs − This has been covered several times in the
past but, unfortunately, we have had a number of people recently who
have experienced difficulty in preparing hard discs for use. While we
cannot provide a step-by-step description, since all the controller
cards are supplied with different software, many of the operations which
need to be completed are similar.
8.12
Remember that, for your particular system, you will need to read the
manual supplied with your hard disc controller card, or the HFORM
section of the manual if you are using a native drive (for example an
IDE drive on the Risc PC).
8.12
The most important point is that you MUST NOT actually format the drive.
If you do, you are more likely to damage the drive than make it usable!
All modern drives have the low level formatting laid down during the
manufacturing process, and trying to reformat the drive is likely to
damage the original formatting, but not completely replace it, rendering
the drive unusable.
8.12
Instead you need to initialise the drive. The precise wording will
depend on your controller card − Morley SCSI and HForm give you an
option to “Format or just Initialise the drive”, and the Cumana SCSI 2
card requires that you set up ‘partitions’ on the drive. The
initialisation process involves writing out RISC OS information about
the position of files on the drives, contents of the root directory and
so on, but does not do the potentially dangerous low level formatting.
8.12
NCS.
8.12
Quicksort − An error crept into Colin Singleton’s Programming Workshop
last month − at some point, the Basic program detokenised incorrectly.
All the ASC commands should be replaced with a minus sign to make the
program work. Thank you to all those who rang or wrote to point out the
error.
8.12
NCS.
8.12
Screenbanks − Following on from Matthew Hunter’s Programming Workshop
article on screen banking (Archive 8.8 p69), errors may not be displayed
because the error is written to the screen bank being updated, and not
the screen bank being viewed. By using the following procedure, you can
link both screens back together.
8.12
DEF PROCresetscreens
8.12
SYS 6,113,SB_bank%
8.12
SYS 6,112,SB_bank%
8.12
ENDPROC
8.12
The procedure could be called via the ON ERROR mechanism, or at the end
of the program.
8.12
Peter Prewett, Stirling, South Australia.
8.12
Snippet − Snippet is still a useful utility for screen grabs etc, but
refused to perform with my Risc PC. I queried 4Mation and obtained the
latest upgrade (in very short order and at no cost, which prompts me to
raise my hat to them), but still found the same problem of freezing the
machine when I tried to save a screen. The solution to this seems to be
to select a screen mode of no more than 256 colours, upon which, Snippet
behaves like the old friend it has always been.
8.12
Alan Jackson, Oamaru NZ.
8.12
Upgrading Video RAM − When upgrading the VRAM in your Risc PC from 1 to
2Mb, it is necessary to remove the 1Mb board and return it to be
upgraded. You should make sure that you reconfigure your computer to use
a screen resolution/number of colours which is possible even with no
VRAM, before removing the 1Mb board. If you do not do this, you will
find that you will need to reconfigure the computer ‘blind’, as the high
resolution modes are not available if there is no VRAM present, and no
picture will be displayed.
8.12
Fred Williams, Staffordshire.
8.12
Wimp bug (RISC OS 3.10) − If you are a Wimp programmer and have
experienced apparently inexplicable ‘Abort on data transfer’ and
‘Address exception’ errors ‘at’ addresses in the Window Manager module,
especially just after your program has quit, you may be interested (or,
like me, relieved!) to know that the problem may lie in a bug in the
Wimp.
8.12
According to a letter from Acorn, “there was a bug with ‘slabbed’ icons
(those with the R option in the validation flags). If you click on a
slabbed icon, and the program deletes the window it is on, or quits
before the wimp has a chance to redraw it, problems can arise.”
8.12
Hugh Eagle, Horsham.
8.12
Windows on the Risc PC − I would like to warn CD-ROM users that, due to
the fixed palette on the PC card, many CD programs will not work
properly − giving psychedelic colours which can lock up the computer. We
have found by pressing <f1> (in Windows) that the Windows help will be
opened, from which you can return to Windows. This prevents having to
reset the computer. Acorn/Aleph One are working on a fix for this
problem.
8.12
Peter Hughes, Desktop Laminations.
8.12
PD Column
8.12
David Holden
8.12
Many more Acorn computers are now fitted with CDs, and this means that
more software is being distributed on this medium. Increased sales also
means that prices are coming down to more realistic levels.
8.12
The ARM club will soon be producing a CD of PD programs at just under
£20. I don’t know exactly when it will appear, but it should be
available for Acorn World ’95 at Wembley in October.
8.12
APDL will also be producing at least two new CDs. The second Clip Art CD
is nearing completion and this looks even better than the first. No
price has yet been decided, but it should be under £25.
8.12
The second APDL CD will be PD programs. The main reason for this is that
I am fed up with people asking for it! Like the ARM Club CD, this should
be priced around £20. No release date yet but it should be available
before Acorn World.
8.12
New version of Zap
8.12
Version 1.3 of the text editor Zap has now been released. There are lots
of minor improvements and bug fixes, but the main enhancements are
concerned with making it ‘properly’ Risc PC compatible. This means that
redrawing 32 thousand and 64 million colour modes is faster, and the
dynamic memory management of the Risc PC is used, which speeds up some
operations and overcomes earlier problems which could (very rarely)
cause Zap to crash with very large files.
8.12
Instead of the System font, Zap now uses its own bitmap fonts. Dozens of
these are provided, but tools are supplied for you to make your own. (I
have already designed some for myself.) Not only does this mean that you
can have much more detailed characters in high resolution screen modes,
but the size is also variable. The Zap redraw routines are optimised for
8×8 or 8×16 pixel characters, but other sizes can be used. For example,
I am using 8×14. This gives me nicely shaped, easily read, characters,
and also puts more lines on the screen. On a Risc PC, the fact that this
is not an optimum size for speed has little effect.
8.12
This will be of particular interest to people with poor eyesight. By
choosing (or designing) a bigger font, you get larger text. For example,
using the supplied 12×24 bitmap font produces text about the same size
as 24 point anti-aliased. The advantage of using bitmapped fonts is that
they are faster, much easier to customise, and fixed pitch, which is
essential for programming.
8.12
Another nice feature is that Zap can now ‘hide’ the mouse pointer while
text is being entered. As soon as you start to type, the pointer
vanishes, but when you touch the mouse it reappears. You no longer need
to move it out of the way.
8.12
There are also lots of new ‘third party’ modes, and Zap can now load new
modes ‘on the fly’, so you don’t need to load them all when it is
started, but can select them from a menu if you need them later. In
particular, there are email modes, ‘MailMode’ for SMTP/NNTP and ‘Email’
for !TTFN and QEdit files, a LaTeX mode, and I was pleased to see a mode
for SAsm.
8.12
Of course, there are lots of other changes but, unfortunately, the
manual is still not too good. Everything is there, but sometimes it’s
difficult to find. Dominic is aware of this but he only has a limited
amount of time to spend on Zap, and rewriting the various sections of
the manual would now be a major task, so I suppose we shall have to wait
a while for that.
8.12
With all the extra ‘goodies’, Zap now fills an 800Kb disc, even when
compressed. However, a large part of this is not required just to run
it, so don’t worry if you don’t have a hard disc − it can still be used
from an 800Kb floppy.
8.12
This month’s special offer is therefore Zap 1.30. For a copy, send £1 or
four 1st class stamps to me at the APDL address and please tell me if
you can use 1.6Mb discs. u
8.12
Scrabble
8.12
Dave Floyd
8.12
At long last, the Acorn series of computers have a version of Scrabble
that is worthy of the name. There can surely be nobody reading this who
has never played the board game or at least have an idea of how it is
played. Scrabble is probably the most popular board game ever devised
and its popularity never seems to wane.
8.12
The one problem with the board game is that you need to have somebody to
play against. Not only that, but if they are not of roughly the same
skill level as yourself, the game can get boring for everyone concerned,
either being no real challenge or an exercise in masochism. The last
person I played regularly has refused to play me for months, since I
cleared my rack three times in four turns. He claimed I was lucky! The
computer is blessed with infinite patience of course, although I must
admit that after playing against it for two weeks now, I have an inkling
of how my friend felt.
8.12
The package
8.12
Scrabble comes in a printed cardboard box which contains the program
disc, a registration card and a fairly small A5 manual. Some of my
friends who have seen the manual have complained about the small type
used but I found the typeface to be clear and had no problems reading
it. (I did − but I’m older than Dave! Ed.) The manual is an important
part of the package as it is part of the protection method used for the
game. When you load the software, it will prompt you to enter a word
from the manual. This is a most sensible approach as it means that you
can back up your master disc or transfer it to your hard disc without
any problems. As an exercise, I tried to guess which word the protection
wanted without referring to the manual. After two hours I gave up. The
choice is far too wide even though the first letter is already filled in
for you. After you have typed in the word from the manual, Scrabble
loads itself onto the iconbar.
8.12
Options
8.12
By clicking <menu> over the TSP (The Scrabble Player) icon, tastefully
created from scrabble tiles, you are presented with the ubiquitous Info
and Quit, along with Options − these allow you to customise the game to
your requirements and save the settings. One option gives you the
opportunity to peek at the opposing players’ racks in practice mode − a
must for those who always sneak around the table when other human
players go to the kitchen. ‘Confirm moves’ causes TSP to delay its moves
instead of the default where the computer will place its tiles the
moment you have picked up. ‘Advice after moves’ is an option which, once
you have placed your tiles, will show you the best score you could have
attained − it can be very frustrating to see what wonderful moves you
could have done! Next, there is ‘Random choice of first player’ − which
should be obvious and then ‘Highlight last move’ which is almost
essential to see where the computer last went. Finally, you can select
‘Board markings for mono monitors’ and choose to have ‘Sound effects’
which do add to the game and are neither over-loud nor intrusive.
8.12
It is also possible to set the default skill level of the computer to
one that matches your standard of play. Available levels range from A
(‘pathetic’), with a 2422 word vocabulary, an average score of 8 and no
strategical play, to L (‘impossible’), with a mind-boggling 134855 word
vocabulary and playing strategically. The description of impossible is
not an unfair portrayal of the highest level, unless you happen to know
the entire Scrabble dictionary by heart, although I felt that US Gold
should perhaps not have used a description such as ‘pathetic’ for the
lowest level. Its main use will surely be to encourage young children to
improve their vocabulary and it could be disheartening to lose against a
level described as such.
8.12
The game
8.12
Once the options are set up to your liking, one mouse click on the
iconbar will bring up the main game screen and a new game window. The
new game window allows you to select 2, 3 or 4 players and how many are
human or computer-controlled. You can change the computer skill levels
from your default and even give each computer player a different skill
level. The default time limit of 25 minutes will be adequate for most, I
suspect, but you can make it faster if you wish. Although the timer will
always be visible during the game, it is only of importance if you
select Competition level rather than Practice, which allows you to go as
far into minus time as you like. You can also choose which level of
advice you will receive; a good way of improving your play in future
games.
8.12
You can name each human player, but not the computer-controlled ones.
This I found to be a strange omission, as other computer versions of
Scrabble I have seen, such as the BBC version, allowed you to name the
computer players too, thus giving the impression that you were in fact
playing your friends. Even us sad, pasty computer hermits like to at
least believe we are sociable.
8.12
Click on ‘Start new game’ and you are away. The game itself is
completely multitasking so allowing you to get on with other things
while you are thinking. (I cheat and use Impression’s spell-check to
help me find suitable words but beware because it sometimes crashes TSP!
Ed.) The main game window takes up less than quarter of the screen at a
resolution of 1280×1024, yet is very clear and the resemblance to a real
Scrabble board is excellent. Most of the gameplay is carried out by
selecting and dragging tiles or through the button icons at the top of
the window which can be seen on the screenshot on the previous page.
8.12
Other options are available, either through clicking <menu> over the
window or by control key combinations, the most useful being <ctrl-S> to
display an automatically updating score sheet − see opposite. Another
option, also useful for other applications such as crosswords, is <f4>,
which allows you to search through the dictionary for anagrams from a
set of letters. If you are stuck and tempted to ask the program for a
hint, this is the more sporting option as you still have to find a
position to place the word on the board. Clicking on the hint button
finds your best choice and shows you where it can be placed. Both are
really cheating though and, as such, will not be of interest to all the
fine upstanding Archive subscribers reading this. (e.g. to find out who
has the ‘Q’! Ed.)
8.12
One nice touch is that when you are playing a game with more than one
human player, you have to click an icon to display your tiles before
your go, thereby giving your opponent time to look away from the screen.
This avoids spoiling tactics being used, as can happen when you all know
exactly what the other person holds in their hand.
8.12
The flexibility with which the tiles can be manipulated is also
admirable. As well as the random shuffle option, you can drag your tiles
into whatever order you like with the mouse, just as in real Scrabble.
There is also enough room above your tile display to play around with
possible combinations of letters before selecting them all and dragging
them to the board itself. If you select a word and drag it together
rather than letter by letter, you can make them go across or down either
by clicking the icons before dragging or, while dragging, merely by
pressing <ctrl-A> or <ctrl-D>. If you are laying your letters across a
word already on the board, your selection of letters automatically
splits to include those already played.
8.12
There are two rather strange deviations from the rules which I notice.
Firstly, it is possible to pass your go while there are tiles still in
the bag. I have always thought that you could only pass when the bag was
empty and that you should exchange tiles where possible, but the
computer allows you to wait for an opening to attach your seven letter
word to without risking losing it.
8.12
Secondly, it will not allow you to exchange tiles when there are only a
few left in the bag. Mind you, this stops the cynical tactic of leaving
your opponent with Q, J and Z as the last three to pick out, which is
allowed by the rules. Neither of these detracts from the game itself,
however.
8.12
Conclusion
8.12
When starting with an idea as tried and tested as Scrabble it is very
difficult to go far wrong. The care and thought that US Gold have put
into the RISC OS implementation, however, surpasses my expectations. The
inclusion of the whole of the Scrabble dictionary avoids the computer
asking ‘Are you sure?’ whenever it does not recognise a word. I have
also not noticed any spelling errors in the dictionary, such as ‘GPLT’,
a favourite choice of the computer on the old BBC version.
8.12
My only quibbles with the game are very minor and are mentioned above.
They do not detract from the game itself or its addictiveness, although
it would have been nice to have had the option to turn off help
completely, as the temptation to use it does become great at times. It
would also have improved its scope as an educational resource. Nothing
is perfect, however, and 99.9% is not a bad strike rate.
8.12
US Gold deserve to sell many copies of this game and I hope that
interest is strong enough to make them develop further games for the
Acorn market. Other Acorn developers would do well to study their output
and the professionalism that exudes from it. The coding is so good that
the speed is blinding, even at higher skill levels. If you pit the
computer against itself with all levels set to L, the game will be
completed in about 10 seconds. I would certainly like to see what US
Gold could do with board games such as Risk and Campaign, both
notoriously difficult to find human opponents for. A brilliant
implementation of a brilliant game. I cannot praise it highly enough.
Buy it!
8.12
Scrabble is available through Archive for £27. u
8.12
I like Scrabble a great deal and so does Dave, obviously. So, on the
principle I have been applying recently, I tried to do a special deal
for subscribers. Unfortunately, US Gold are not as flexible as some of
the smaller Acorn companies − still, even at £27, it’s very good value
for money. Ed.
8.12
Windows 95 on the Risc PC
8.12
Michael Clarkson
8.12
To make Windows 95: take roughly equal measures of RISC OS and Apple’s
System 7, combine onto a rough base of DOS and (half?) bake for several
years.
8.12
August 24th sees the launch, finally, of Microsoft’s Windows 95; various
beta versions have been made available for some time and, having access
to the final one of these, I spent a weekend getting it running on a
Risc PC. (For those who also have access to a beta, Archive have a sheet
on how I got mine to run – it’s too complicated and of too narrow
interest to include here.)
8.12
(We have put this info, plus a similar article about installation sent
in by Dave Harris, on the monthly disc. Ed.)
8.12
Most important – connectivity
8.12
There are large numbers of PC magazines around which will tell you just
what Windows 95 feels like, and I will give something of a RISC OS
user’s view later, but I make no apologies for beginning with what I see
as the most important aspects of Win95 for Acorn users – how does it
affect (enhance?) Acorn/PC connectivity? This has been the subject of
much discussion in Archive recently, e.g. the text transfer series.
8.12
The very good news is that it enhances it considerably. For me, the
single most exciting package bundled with Win95 (and I trust it will be
bundled with the release version) is a package called WordPad which, for
those who’ve used Windows 3.1, is an enhanced version of Write, a basic
wordprocessor. The good news is that WordPad has the ability to load and
save both RTF (Rich Text Format) and Word for Windows files, and it can
convert between them. Thus I can take a document produced in Word for
Windows, pass it through WordPad, saving it as RTF, and load it into
Impression, Fireworkz, Ovation etc. – indeed any Acorn application which
will load RTF files, which is (slowly) becoming the standard for text
file transfer on all platforms.
8.12
WordPad doesn’t support all the features of Word for Windows (Microsoft
still want you to buy it!), but with the documents I have used, all
word-processing features have transferred correctly (as opposed to DTP
features, like embedded pictures, which do not transfer yet). The
process is reasonably quick and quite painless – I can transfer almost
any document in less than 5 minutes, and have it all correctly
formatted.
8.12
As well as being able to load Word files, WordPad can also save them, so
if you can save in RTF format from your Acorn application, you can now
create a Word6 file. Computer Concepts have recently released an RTF
saver (£33 through Archive) which makes transfer from Impression
possible, and this works just as well and just as quickly as going the
other way, and I think that Fireworkz and Ovation can also save RTF
files. As many will know, PC users would much rather have a Word6
document than some strange RTF file, even though Word can happily load
such files; passing the RTF file through WordPad enables you to produce
the Word6 file without having to spend several hundred pounds on buying
Word for Windows yourself – definitely good news.
8.12
Windows 95 therefore brings to Acorn users the closest thing we shall
get to file compatibility with what must surely be the most used word
processing filetype in the world – and it’s free (though Win95 itself
won’t be – but then you don’t get a version of Windows with the 486
card, so you’ve probably got to buy one anyway). I say this is the
closest thing to file compatibility, because Microsoft will not release
the file format of Word, and therefore a Word loader/saver for Acorn
applications is most unlikely.
8.12
The second piece of good news, as far as connectivity goes, is that
Win95 incorporates an excellent feature called QuickView. This enables
you to view a document created by an application even if you don’t
actually own the application. Thus even though I don’t own Excel, I can
view (on screen) files produced by it. This is clearly very useful to PC
users as well as Acorn users, but it is particularly so for us since we
already have perfectly good spreadsheets, wordprocessors etc. and don’t
want to spend money on buying PC versions just to run on the PC card.
8.12
However, QuickView only allows files to be viewed – not saved or even
printed, though when Win95 runs in a RISC OS window (at present, it only
single-tasks), it should be possible to grab a sprite using the Paint
screenshot facility and print it out (the appearance will be poor, but
readable), and possibly the file could be saved as text, which would be
more useful. QuickView seems to be able to cope with the following
filetypes: AmiPro, BMP, Word6, RTF, Lotus 1-2-3 (WKS and WK4),
WordPerfect 5 and 6, Excel 5 and a few others I was unable to identify.
8.12
I’ve only been able to test the Word6 (DOC) and Lotus 1-2-3 (WK1)
viewers. (WK1 is not a file directly supported, but it presumably
treated it as WKS or WK4.) Both these did what they said they would,
though the Word viewer didn’t give as good a view as WordPad, which even
showed graphics embedded in a Word document; QuickView was unable to.
However, the range included covers most of the major PC file types and
should prove most useful, if only for reading a document before deciding
to ask its author for a version in a format you can use. For comparison,
the closest application in the Acorn environment must be the Artworks
viewer, which displays files produced by Artworks but won’t alter, save
or print them.
8.12
Bad news – system requirements
8.12
All of the above is good news for Acorn users. There is, however, bound
to be bad news. First, Windows 95 eats up memory – RAM is just about
manageable, since it needs 4Mb minimum (which means having 6 or maybe 7
on your system as a whole), although it will run rather better and much
faster with more (I can only give it 5Mb at most, but am told it runs
quicker with 8 or more); hard disc space will be more of a problem for
many people, I think, since installing Win95 requires around 90Mb – and
that’s without adding any applications, each of which could well be 40Mb
or more. Of course, at present, Win95 is only in its final beta form,
and the release version may have slightly different requirements –
probably a little more hard disc space, even for the average
installation, and for a “full” installation, considerably more may be
needed. Because it is only at the beta stage, Acorn and Aleph One are
not yet supporting Win95 (the official line is that it doesn’t run), but
they will do so soon after it is launched; my version would only run in
16 colours and only in single-tasking mode, but that was better than
nothing.
8.12
Windows 95 – RISC OS user’s view
8.12
So what does Windows 95 actually look like? Time and space only permit a
brief overview, but I hope I may, in further articles, be able to
explore more deeply − comments from other readers, maybe those using
Win95 on “real PCs” would also be very welcome.
8.12
My first comment in this article does, in many ways, sum up the look of
Win95. Like RISC OS, it has an icon bar (known as a taskbar), and
context-sensitive pop-up menus, produced by using the right mouse button
(poor PC users don’t have a middle one). At startup, the taskbar only
has one item on it, imaginatively called “Start” and, from here,
applications can be launched, files opened and system settings changed –
each of these has its own submenu and corresponds closely to the Apps
and disc icons and !Boot/Configure application on the Risc PC.
8.12
When an application is launched, it is placed on the taskbar, and a
window opened automatically. As in RISC OS, the current window has its
title bar highlighted, and windows can be dragged and re­sized (though
still only in outline) and closed using icons at the top of the window;
there is still no “send-to-back” icon, the absence of which I find
annoying, both in Windows and on the Mac. There is, however, also an
icon at the top of the window which quits the application, removing it
from the taskbar.
8.12
The taskbar pop-up menu is less useful than under RISC OS, being
concerned (as far as I can see) only with the position and appearance of
the window – duplicating, in effect, the icons at the top of the window,
though it may be open to wider use by third-party applications. The
icons on the taskbar are rather wider than under RISC OS with the
application name next to the icon, not beneath it, which has the benefit
that the taskbar is less high, but fewer applications can be fitted onto
it. When its width is exceeded, rather than scrolling as RISC OS does,
each of the application names gradually gets squeezed, becoming “Media
P..” instead of “Media Player” etc., which could become something of a
problem, and is certainly quite ugly, when used on a machine with lots
of RAM running a number of applications.
8.12
Switching between applications is done as in RISC OS, i.e. by clicking
in their window or on their icon on the bar to bring their window to the
front. A rather nice feature is that the taskbar can be made to stay on
top, so that windows which are moved to cover it in fact disappear
behind in (the RISC OS iconbar can be brought to the front using <shift-
f12>, but I’m not aware of a utility to keep it at the front all the
time.) Alternatively, the taskbar can be made to disappear and pop up
only when the cursor is placed at the bottom of the screen – nice in
theory, but since the icons on it seem to be loaded from disc each time,
it takes several seconds for it to pop up (again, maybe more RAM would
counter this).
8.12
When it comes to multitasking, Win95 nearly keeps up with RISC OS, and
with a faster processor and more memory, I guess it comes very close;
background printing is certainly more effective. However, Microsoft has
not only been looking to Acorn. Win95’s icons have more of a Mac look to
them, and the way things are placed on the desktop is more akin to the
Mac than to the RISC OS pinboard, though the differences are not great.
Again, the Recycle Bin is very much like the Dustbin on the Mac and is
used for deleting programs, which are kept in a buffer until you ask for
the bin to be emptied. So if you decide you do need that file after all,
it’s still there – there are PD programs available for RISC OS which
provide a similar function.
8.12
To sum up, Win95 is certainly easier to use than Windows 3.1,
particularly for those of us who are used to a decent graphical
interface – a friend installed Win95 on his 486DX66 at the same time as
I installed mine on the Risc PC and, initially, he didn’t like it – it
was a foreign interface (it is quite different from Windows 3.1),
whereas I found it really quite natural, and ended up teaching him how
to use it – Microsoft have unashamedly been learning from Acorn, and it
shows, so if you are about to buy a version of Windows for use on a 486
card, or indeed on a standard PC, I would strongly suggest you go for
Win95 – it will be more familiar, offers more connectivity, and is also
almost bound to become the new standard, eventually.
8.12
However, although Win95 is a much more friendly operating system than
3.1, and is much closer to RISC OS, its heritage is not entirely hidden,
and the first thing RISC OS users will notice is the frequency of hard
disc accesses which take place for no apparent reason – if you want to
give your hard disc a real workout, run Win95 on it! This is because,
like DOS and 3.1, Win95 is a disc-based operating system, parts of which
are loaded from disc during startup, and parts of which are loaded as
they are needed, a bit like RISC OS modules are loaded by an application
if necessary, except that Win95 loads rather more, and takes much, much
longer. Some of this would probably be reduced by increasing the RAM
available, but the problem certainly doesn’t go away altogether.
8.12
Win95 uses a swap file, a little like the RISC OS scrap file, except
that RISC OS doesn’t use the scrap file all that often, and you hardly
notice when it does. Win95 needs a swap file of around 5Mb which is one
of the reasons so much hard disc space is needed, and you certainly
notice it chugging that amount of information on and off your hard disc
every couple of minutes.
8.12
(To get some idea of how the disc access slows the whole thing down, put
thirty applications into a directory, restart your machine and open the
directory – the machine waits while all the application sprites are
loaded – a similar effect to most operations under Win95. Alternatively,
try using the Fonts section of the Configure application to reduce
“Cache bitmaps up to” to 0 point – the system runs but looks ugly and
every action is delayed, e.g. try dragging a couple of windows past each
other. However, the delay is still not as great as when Win95 is
accessing the hard disc.)
8.12
Despite these criticisms, Win95 is much easier to use than 3.1, and may,
in fact, be a little quicker. It does run reasonably on a medium spec.
Risc PC – I have this article loaded into Impression and have Win95
running at the same time, and can swap to Win95 by clicking the PC icon
on the iconbar, and back again by clicking the middle button – try
asking a Mac user with Apple’s PC card to do that! (My PC card currently
has 4Mb of memory allocated to it, I have a (6+2)Mb ACB15 and am now in
a 256 colour 1024×768 mode running Impression while the 486 card sits
“frozen” in the background – really quite usable.)
8.12
Finally, while Microsoft have been learning from Acorn, there are things
in Win95 which Acorn would do well to consider closely. (a) The Internet
support, which I’ve been unable to test, is said to be reasonable,
though not as good as IBM’s OS/2 Warp, (b) the QuickView facility
(described above), (c) the amount of system configuration possible
(almost everything about the desktop can be changed – colours, sizes,
fonts etc.), and (d) relatively small but useful ideas, like being able
to keep the tool (icon) bar at the front. Oh, and Windows 95 supports
filenames of up to 256 characters. (DOS extensions are no longer shown
– a file called “Letter to the bank January 15th 1995.DOC” looks a bit
silly. But then, so does “Bank950115”, which is the best RISC OS can
manage.)
8.12
If you have views on this issue, write to me at Rigg’s Hall, The
Schools, Shrewsbury, SY3 7AZ. u
8.12
School Admin with Acorns
8.12
Chris Wragg
8.12
Are there any other schools out there who use their Acorns for
administration?
8.12
I guess there are a number of primary schools that do so, particularly
if PIMS is as good as Mike Tomkinson claims, but secondary schools must
be few and far between. Certainly in Norfolk, I am the only head with a
Risc PC on my desk, and I am regarded by most of my colleagues either as
a freak, or as a rare computer buff who only uses Acorns because I am an
enthusiast. For them, PCs or Macs are the only machines they know and
understand. It is curious, isn’t it, that in the education world where
Acorn have such a major slice of the market, they have generally failed
to provide for the managers!
8.12
Go for compatibility
8.12
No, my school is not 100% Acorn, but it is probably closer to 100% than
most. When I started as head in 1983, there were no computers in the
school at all − a golden opportunity to develop a coherent system, not
on Pets or Apple IIs, but based on BBCs. In spite of occasional
pressures to digress from this standard, we have stayed with Acorn to
the present day. My main argument has always been one of compatibility −
pupils and staff all know and use the same type of machines. This has
proved a much stronger argument than simply telling people they are the
best, and works well on governors too! This has had particular relevance
in two areas.
8.12
Firstly, I have always encouraged my staff to use the machines for their
own work. This means that when they are teaching IT components of the
National Curriculum, they are already familiar with the system used in
the classroom. The problems of IT literacy among staff is still a real
one, but greatly eased by using the same system in every part of the
school, and we have now even reached the stage where most staff prefer
to sit down personally at the computer to write their reports (on Cogent
Software) rather than fill in the OMR sheets.
8.12
Secondly, when we introduced Records of Achievement a few years ago, we
used a combination of Acorn software. Pupils originally prepared their
own profiles on Interword; now they do so in Style; staff prepare their
sections in the same way. When they are all collated on the network,
they are printed out using Style on the standard forms. Everyone
involved at every stage used the same system.
8.12
Non-Acorn machines?
8.12
Macs and PCs have usually been ‘given’ to us! We had a Mac given to us
as part of TVEI which was supposed to have been used for TVEI budget
administration. It was my introduction to Filemaker, and to Pagemaker. I
was impressed by the software, but I hated the poky screen and the
prices! We bought a second machine on the principle that we could not
afford to use it seriously without a second being available, and they
gave good service for a couple of years until RISC OS was born. The Mac
experience was a valuable one from which to compare RISC OS with Macs,
and there was no doubt at all which was preferable! Even now, a few
years later, whenever I have to use a Mac (they are used in all Norfolk
Primary Schools for administration) I shudder to see how little they
have moved on in terms of the operating system.
8.12
And then there were the PCs. I tried hard to persuade my Business
Studies teacher to use Acorns, and she genuinely tried for a few months.
Unfortunately, they were too good at their job, because word processing
examinations still insisted on equally spaced fonts, and although she
used Ovation for DTP, a ‘free gift’ of 12 PCs from a nearby centre that
was closing down swung the argument irreversibly towards Microsoft
Works! More recently, I have succumbed and agreed to an order for a PC
to run the ECTIS CD-ROM in the Sixth Form Library. Most Careers and
Higher Education information now comes on PC CD­ROMs and, cost for cost,
the PC is the cheapest solution for such a dedicated task.
8.12
And then there is the finance system, purchased and installed by County,
and run on the PICK operating system on a Compaq 386. (Has anyone else
heard of PICK?) The software was written in-county, and does an
excellent job, but the machine is useless for any other purpose. Like
the PC for CD-ROMs, it has become a one-task dedicated machine.
8.12
Staff issues
8.12
Being an Acorn school in all other respects does provide some
interesting opportunities for observation. For example, when new office
staff have to learn how to use RISC OS, how do they adapt? It is not
readily understood by many Acorn enthusiasts that the system is NOT so
easily picked up by your average secretary! Most clerical staff are not
interested in computers. All they want to know is sufficient to do their
work and no more. Drag and drop, and multitasking, are totally foreign
experiences that they would rather not know. The enthusiast knows that
these are key features of RISC OS that they could never be without, but
the average office worker could not care less.
8.12
In general, staff learn quickly to do the basic things. Our office uses
Ovation, Eureka, and an in-house database called Maxifile (available as
Freeware through APDL if you are interested). However, they are still
very dependent on me and other IT specialists on the staff when they
want to do anything slightly out of the ordinary.
8.12
The four other senior staff also have Acorns on their desks − one Risc
PC, two A5000s and one with an A3000. Two new deputies have had
differing reactions. One who is an experienced user of PCs has adapted
quickly and loves working in the desktop as opposed to Windows; the
other who also has strong PC experience has struggled with a particular
software package (that I will not name!) that developed numerous strange
bugs, and has been put off Acorns for life! Hopefully, we will yet
convince her!
8.12
Why use Acorns?
8.12
I sometimes wonder if I am doing my school a disservice by sticking with
Acorn. Why are all the others so happy with their PCs and Macintoshes?
Should I really be using Simms? Of commercial software, we use Eureka,
Ovation, MicroLibrarian and Cogent Software, but we also use a number of
programs I have developed myself − Maxifile, TimeDesk (a timetabling
package), Week95 (an OMR registration program), and Options (yes, for
sorting options!). Am I wrong to stick with my Risc PC? Should I start
using my PC card, which is fitted, but only used to run the (awful) SCAA
SATs program?
8.12
I would genuinely like to know if there are any other ‘freak’ secondary
heads like me who run their schools on Acorns!
8.12
(Those who had an early version of Maxifile that used to be available on
an Archive Shareware disc may like to know that it is now in version 4,
runs in the desktop, and has many enhancements since those early days.
It is available as freeware through APDL. If anyone is interested, I am
considering putting out the other programs noted in this article as
Shareware − if there is anyone out there, that is!)
8.12
If you have any ideas, comments, questions, etc, please contact me at
Charles Burrell HS, Staniforth Road, Thetford, IP24 3LH. (01842-
763981). u
8.12
Clan Acorn Column
8.12
Simon Ogilvie
8.12
Acorn’s web site online at last!
8.12
Acorn’s long-awaited World Wide Web pages finally went online on Monday
19th June and I can say it was worth the wait! Initial access to the
site is from the URL http://www.acorn.co.uk/ which brings up a
‘signpost’ page pointing to the four parts of the Acorn group (Olivetti
Telemedia, ARM, Online Media and Acorn Computers). The Acorn Computer
pages are organised as a ‘virtual village’ with a large clickable image
on the home page containing pictures of various ‘buildings’, including a
‘library’, for online documentation and past press releases, an
‘airport’, for links to international Acorn-relevant homepages and, most
importantly a Clan Acorn stand, which can be clicked on for more
information.
8.12
As mentioned in my last column, the Clan section includes some password-
protected pages, accessible only to Clan members. Currently (3/7/95)
these pages only contain copies of software and information already in
the Clan packs. The public-accessible Clan pages include forms to email
‘The Chieftain’, alias Chris Cox, information on how to join and details
of Clan events.
8.12
For those without access to graphical browsers, the pages can be
accessed using the text equivalents of the clickable images but, of
course, the feeling of a ‘virtual village’ will be lost.
8.12
The ARM pages are currently under development, but there is a link to
the ARM US pages which contains some useful information.
8.12
The Olivetti Telemedia page gives some interesting information on the
relationship between Olivetti and the various Acorn Group companies,
including who owns what proportion of each of the companies. Other than
that there is very little about Olivetti Telemedia, but there are some
links to the main Olivetti Web sites in Italy and the US.
8.12
The Online Media pages are also under development so there is only a
‘front-sheet’ with a small amount of information on it.
8.12
All the front-sheet pages are designed in the same style, which gives a
good uniform feel, and there are copious links to other parts of the
site making it easy to navigate. There has been some criticism of the
decision to use white as the background colour (which is not entirely in
line with the Acorn Style Guide recommendations!) but they certainly
make the text a lot easier to read than it would be on a textured
background.
8.12
The Acorn Computers pages are by far the furthest developed of the group
and are certainly well put together. They show every sign of developing
into an informative and useful Web site.
8.12
RISC OS version 4?
8.12
Other developments which may be of interest to Clan members include the
announcement in the Usenet newsgroups of a project called Tornado. This
is designed to be a replacement for RISC OS which the development team
aim to release in late August! The design apparently already includes:
8.12
  * Virtual memory
8.12
  * Relocatable auto-extending heaps
8.12
  * OLE and hotlinked files
8.12
  * TAOS style subtasks
8.12
  * Preemption
8.12
  * A tornado shell
8.12
  * Crash-protection
8.12
Suggestions for other inclusions are invited by the team, who can be
contacted via Niall Douglas’ email account −
[e-mail].
8.12
For those who remember the original ‘Arthur’ OS which came with the
first Archimedes machines, this project may sound familiar, as Computer
Concepts started developing an Arthur replacement before Acorn released
RISC OS 2. Acorn’s release obviously killed off CC’s project completely,
and it would seem likely that the Tornado project would also become
untenable if Acorn were to release a new version of RISC OS that
contained some or all of these features. However, with such an
aggressive timescale for planned release, the Tornado team seem likely
to beat Acorn to it and will therefore stand a better chance of
survival. We’ll just have to wait and see....
8.12
New Publisher version
8.12
One other interesting snippet of information gleaned from the Newsgroups
is that CC are apparently planning to release a new version of
Impression Publisher in time for the Acorn World show. This is in direct
contradiction to their previous stance which was that all development on
Impression had now stopped, in favour of their new PC work. The change
in position may well have been prompted by the imminent release of
Beebug’s Ovation Pro which clearly challenges Publisher for the title of
best DTP package on the Acorn platform.
8.12
Stop Press
8.12
I’m probably too late (again...) but Acorn have just put some info on
the Clan Web page about the new FileCore module. They are inviting Clan
members to apply to join a beta-test trial of a soft-loadable version of
the module. The Web page explains that they have successfully tested it
with 1Gb IDE drives and 9Gb SCSI drives, and that it should be capable
of supporting discs up to 128Gb. As this is only a beta-test, Acorn
cannot guarantee that the code is completely bug free (can they ever?!),
so Clan members wanting to enter the trial have to be aware that using
the new filecore could corrupt their hard drive. If this is seen as an
acceptable risk, then a form can be filled in on the Web page, to
register. Clan members without Web access will be sent news of the trial
with the next Clan pack.  u
8.12
Starting Basic
8.12
Ray Favre
8.12
A dozen years ago, if you wanted to learn how to program in BBC Basic on
an Acorn machine, there were at least twenty books available − including
several for beginners.
8.12
Today, there are only a handful of corresponding books for RISC OS
machines; most concentrate on Wimp programming and (necessarily) assume
that the reader is already proficient in BBC Basic.
8.12
This series will attempt to fill the gap a little. It will be aimed at
those who are new or fairly new to Basic programming and will help them
to build the skills and confidence to go on to tackle Wimp programming.
(So the series will keep the relevance to Wimp programming in mind, even
though that might not always be evident.)
8.12
The draft Contents List for the series is shown below, and my main
assumptions at the start are:
8.12
• You have a RISC OS Acorn computer with BBC Basic V available.
8.12
• You have copies of the Welcome Guide (WG) & User Guide (UG) for your
computer (and you’ve read them!). There will be frequent references to
these documents, in the form “UG (or WG) Chapter/Subject heading)”. Page
numbers wouldn’t work, as different versions exist.
8.12
• You can carry out the commonly-used operations in the Desktop mode;
such as closing/opening directories, starting applications, dragging &
dropping, etc.
8.12
If you think the Contents List needs changing, or if my assumptions are
wrong, or you’ve got specific queries, then please let me know. Things
can easily be modified to please the customer!
8.12
The only other points worth mentioning in this introduction are:
8.12
a) There’s only one way to progress − sit at the keyboard and ‘play’.
You won’t damage the computer − although you will probably ‘freeze’ it
up sometimes and lose some data occasionally − but you’ll learn faster
through your mistakes. The series will be ‘hands on’ as much as
possible.
8.12
b) There is rarely only one way of achieving an aim in BBC Basic. So,
these articles will not be ‘tablets of stone’. Let us all know when you
find a different (or perhaps better) way to achieve the same end. It
makes for a better column.
8.12
Intended series contents
8.12
1  What is a Basic program?
8.12
2  Variables (Types, Naming them), simple input and output
8.12
3  Basic keywords and tokens
8.12
4  Program structure (Wimp and non-Wimp), libraries, PROCs/FNs
8.12
5  Calculations (precedent order, standard functions)
8.12
6  Direct data storage/retrieval (READ/DATA, indirection operators)
8.12
7  Branches and conditionals (All the ‘loops’ and ‘branches’)
8.12
8  Input
8.12
9  Output
8.12
10  Files
8.12
11  Simple graphics (PLOT codes)
8.12
12  ..........
8.12
What is a Basic Program?
8.12
Any computer program is a set of instructions telling the computer to
carry out certain tasks. The particular instructions used depend on the
language the programmer is using; and this series will be using the
Basic language. More specifically, and we need to be specific as there
are many ‘dialects’, we will be using BBC Basic V (with some mentions of
BBC Basic VI).
8.12
In BBC Basic V − referred to as ‘Basic’ from now on − the available
instructions are usually single words (keywords), in more or less plain
English. They are always strictly in capital letters. Thus, PRINT, INPUT
and CIRCLE are all Basic keywords, each telling the computer to take
some action (closely matching what the word says, which makes Basic
programs reasonably easy to understand in print.) There are about 150
Basic keywords which is really a very small number for learning
purposes.
8.12
A Basic program is constructed by writing the instructions line by line,
each line starting with a number, and ending with a press of the return
key (see WG “Keyboard”). A typical line might be:
8.12
110 PRINT“Press any Key”
8.12
This line has one instruction on it, but you can put more than one by
separating them with a colon. Thus:
8.12
120 MOVE 0,0:DRAW 100,100:DRAW 512,512
8.12
contains three instructions. The only limit to this is that one line
must not exceed about 240 characters (three 80-character lines is a good
guide − an explanation of the precise limit needs to wait a while).
8.12
However, it is not good practice to use multi-instruction lines when
developing a program, so we will normally use single statement lines in
this series.
8.12
The computer deals with these lines of instructions in line number
order. However, some keywords deliberately require the computer to leave
the strict numerical sequence completely or temporarily − and thus the
programmer controls the structure and flow of the program.
8.12
Basic lines can be numbered using whole numbers (‘integers’) from 0 to
65279, which is more than adequate for all normal purposes. In fact, it
is conventional to start at 10 and go up in steps of 10 − and even that
usually copes.
8.12
First steps
8.12
To get started, switch your computer on. (If it’s not configured to
start up in Desktop mode, type “Desktop” when the Command Line prompt
appears.) At the bottom righthand corner will be the green Acorn ‘Task
Manager’ symbol (or one of its earlier equivalents perhaps) (WG ‘RISC OS
Desktop’). Click with <menu> on this symbol and then click with <select>
on ‘Task Window’. A small window with a white background will open and
it will have a ‘*’ symbol (a ‘prompt’) in its top lefthand corner, with
a thin red ‘caret’ next to it. This latter is the text cursor which
tells you where your keyboard input will next appear (WG ‘Keyboard’).
You are now in command line mode within a desktop window, usually much
more convenient than ‘true’ command line because the desktop continues
as normal in the background.
8.12
(Try things out − type some nonsense like “zzz” then press <return>.
You’ll get an error message “File ‘zzz’ not found” and the next line
will be set up with the ‘*’ again, waiting for you to type something
else. It doesn’t sigh and roll its eyes upwards!)
8.12
This time, type:
8.12
BASIC <return>
8.12
(The <return> bit means, “press the return key”.) You’ll get a short
message confirming that you are now in Basic and giving the Version
Number (worth noting, by the way) and how many bytes of RAM (WG
‘Glossary’) you have available for Basic. Also, the prompt has changed
to a ‘>’ symbol − which is the normal Basic prompt.
8.12
Now type the following, not forgetting to press <return> at the end of
each line:
8.12
10 REM>Test
8.12
20 :
8.12
30 :
8.12
40 string$=“Second Try”
8.12
50 PRINTstring$
8.12
60 :
8.12
70 PRINT60+(2*9)
8.12
80 :
8.12
90 integer%=8
8.12
100 real=12.5
8.12
110 PRINTinteger%*real
8.12
120 :
8.12
130 END
8.12
Provided you use the same line number as I have, it does not matter in
which order you type the lines. The computer would still execute them in
number order, and there is a command to list the program in the proper
order, called LIST. To show this in action now type:
8.12
20 PRINT“First Try”
8.12
(Don’t forget the <return>)
8.12
then:
8.12
LIST
8.12
(Again, don’t forget the <return>)
8.12
You will see a listing with the revised line 20 in its right place. You
have now entered and amended a Basic program. The program resides in
your computer RAM memory awaiting your next action.
8.12
Before going any further, ‘Get into the Saving habit’: in this case
simply type:
8.12
SAVE
8.12
(Definitely the last reminder about <return>)
8.12
and you will find a new file called ‘Test’ in the display of your
Current Directory (UG ‘Star Commands’), with the reassuring white-on-
blue Basic file icon. The name ‘Test’ is taken automatically from the
first line of the program if you use the preceding REM> format.
8.12
You now have the program safely tucked away in case problems occur.
“Always save it before you RUN it.” (I won’t sermonise further about the
need to save your work frequently − every five minutes if you’re typing
a long listing. None of us takes any notice until we each learn the hard
way!)
8.12
To reassure you that the program does exist, type:
8.12
RUN
8.12
Is the result what you expected? (Not to tempt fate, you should see
“First Try”, “Second Try”, “78”, “100” printed on separate lines − then
the Basic prompt again.)
8.12
Although it is only a small program, it contains some important items
which we will start exploring next time. It uses some direct values
(lines 20 & 70) and introduces ‘variables’ (string$, integer% & real)
and shows how they can be substituted for direct values in an
instruction. And, not least, it shows how empty lines can help to make
the listing more understandable by splitting it up into logical
groupings.
8.12
Using Edit
8.12
It’s important to know how to use Basic from the command line, but there
is a much easier way to enter, edit and run Basic programs. You can use
Edit which came with your computer, and we’ll normally be using this in
future.
8.12
So, close the Task Window, clicking <select> on ‘Discard’ when asked.
Now click <select> on your ‘Apps’ iconbar icon and double-click on the
!Edit icon. When the Edit icon appears on the righthand side of the
iconbar, click <menu> over it and select ‘Basic’. Now a fairly normal
desktop window opens (an Edit window in this case) into which you can
type or drag a Basic program. Note that now you do not have to use line
numbers  − Edit will automatically insert them for you when you save a
listing. (The price of this convenience is that now you must ensure the
lines are in the correct order before you Run the program). You can also
drag a Basic program to the Edit iconbar icon − in which case, it will
detect it as a Basic program and open a new window with the program
listed.
8.12
Purely to get used to using Edit for Basic, type in the above short
listing again, this time without the line numbers. Also, change the
first line to:
8.12
REM>Test2
8.12
Then press <menu> over the window to reach the SAVE option. Enter
“Test2” in the Save Box as the title of the program and drag it to the
same directory as ‘Test’. They will probably appear side by side.
8.12
If you then double-click on either file icon, the program will run
without further ado − producing its results in a small window like the
previous task window and ending with a message for you to “Press SPACE
or click Mouse to continue”. When you comply, the screen will clear and
then reappear as it was before you double-clicked to run it.
8.12
(There’s plenty to ‘play’ with to keep you going until next time! Try
adding line numbers to just some of the lines in the Edit window and see
how ‘user friendly’ Edit is when you save it. Also read the Edit section
of the User Guide to find how to show or remove line numbers in the Edit
window.)
8.12
Any ideas, questions, suggestions etc? You can contact me at: 26 West
Drayton Park Avenue, West Drayton, Middx. UB7 7QA. u
8.12
Choosing a Printer
8.12
Dave Floyd
8.12
For all the rhetoric of the early eighties, the paperless office has not
emerged and it can safely be assumed that we will not see its coming in
the foreseeable future. Hardcopy is more portable and it can be
distributed amongst people who do not own computers, to name but two
reasons why this will remain true for the foreseeable future.
Personally, I find hardcopy far easier to proof-read too. So, there are
many reasons why a printer soon finds its way to the top of any computer
owner’s want list.
8.12
This article is intended to be a supplement to the feature on printers
in Gerald’s Column which can be found in Archive 8.10 pp33-37 and, as
such, should be read in conjunction with it. I am, of course, writing
with the benefit of hindsight and where our opinions differ, will
attempt to explain my reasons. This should not be taken as an inference
that I consider my views to be more valid than those expressed by
Gerald, merely different. You pays your money and you takes your choice.
8.12
Daisywheel printers
8.12
I can only think of two real reasons for buying a daisywheel (or golf
ball) printer. The first would be that you are involved in a branch of
business where your customers like to think that all correspondence has
been individually typed and not produced on a computer. The output from
a daisywheel is no better, and no worse, than that produced by a
typewriter and the finished item is indistinguishable.
8.12
The second would be for those who have friends who visit and outstay
their welcome. Start printing out a four page document in the corner of
the room and they are certain to be clamouring for the door by the end
of page two.
8.12
Daisywheels are fairly slow when compared to other printers and produce
an immense amount of noise due to their design. While I am sure that
there are many out there doing sterling service as second printers, I
would suggest that to buy one as your Acorn’s only means of
communication with the outside world, is to nullify many of the
advantages of a computer as opposed to a typewriter.
8.12
Dot matrix printers
8.12
The outright winner of the ‘printer war’ in the early 1980s was the
humble dot matrix printer. Its success was due to a combination of
flexibility, cheap running costs and reliability in comparison to the
other types of printer available at the time. Development on the format
carried on apace until the mid ’80s, when printer companies finally ran
out of ideas to improve on the output quality. The dot matrix design has
its limitations, but it has to be said that, if you are on a very tight
budget, there is no real alternative even now. As many of the reasons
for buying one nowadays will stem from financial considerations, I feel
it may be of use to briefly highlight the five types of dot matrix
printer that you are likely to encounter in the secondhand market.
8.12
8-pin dot matrix printers were the first to appear and should be avoided
if at all possible. Due to the logistics of fitting the alphabet into an
eight dot high grid, they had no true descenders (tails on letters such
as ‘y’ for instance) and were only capable of producing very dotty
images.
8.12
Epson’s dominance within the dot matrix field was secured by their
inspired idea of adding an extra-pin to the printhead to create a 9-pin
printer. This enabled letters with tails to have some semblance of
normality to the reader. The problem of quality was still predominant,
however, until the emergence of near letter quality or NLQ printers.
These provided an improvement by printing a line of text then returning
the printhead to the beginning of the line and printing it again at a
slight offset, in order to fill in the gaps between the dots. Although
this did provide an advance, it should be borne in mind that the
description ‘near letter quality’, when attached to 9-pin technology, is
a marketing euphemism as bold as that of Windows software, which claims
to be intuitive and user-friendly.
8.12
The next step for dot matrix printers remains Canon’s only real
initiative in this arena before they moved onward to the development and
production of inkjets. By doubling the number of pins to create an 18-
pin head, they theoretically made it possible to produce NLQ type
quality with one pass of the printhead, cutting printing time by half.
You are unlikely to come across many of these printers, as what must
have appeared to be a pioneering move on the designer’s board, proved to
be a classic example of too little, too late.
8.12
Almost simultaneously came the launch of the 24­pin printer which,
combined with a price war between the printer manufacturers, effectively
swept away everything that had preceded it relatively quickly. Most of
the newer models that I have come across feature three different
qualities of output. Draft, which provides a quick yet dotty texture;
LQ, which prints each line in two passes of the printhead at an offset;
and NLQ, which prints each line three times, effectively giving the
ultimate quality possible from dot matrix technology. At NLQ setting,
the quality is surprisingly good and can be used for most classes of
business correspondence, although the downside to this is the volume of
noise created and the speed of printing.
8.12
For completeness, I will briefly mention the fifth member of the dot
matrix family, the 48-pin. Launched as a last ditch attempt to reverse
falling market share for dot matrix printers at the high end of the
market, the difference in quality produced in comparison to a 24-pin at
NLQ setting was effectively nil. The extra pins enabled its printing
speeds to be raised due to cutting down the number of passes made by the
printhead. However, dot matrix had had its day and the price overhead
commanded for 48-pin technology ensured its rapid disappearance in the
face of inkjet and affordable laser printers which had recently become
available.
8.12
Dot matrix round up
8.12
Although I mentioned the secondhand market earlier in this section, I
would advise against taking that route in regard to dot matrix printers,
unless you have a good knowledge of the pedigree of the printer and can
carry out extensive testing before buying. There are two moving parts on
a dot matrix printer, the transport and the pins in the printhead.
Should either of these prove to be faulty, the cost of repairing them
will often prove to be more expensive when added to the secondhand price
than a cheap new 24-pin printer would have been.
8.12
Colour options are also little more than gimmicks. They may appear at
first sight to be cheap add-ons to the basic system, but the relatively
high price of multi-coloured ribbons will mean that most are unlikely to
make use of the option once the novelty has worn off. That was certainly
my experience and that of others whom I have known who succumbed to the
temptation. The poor quality of dot matrix colour printing makes it far
more effective to stick with simple monochrome line art to embellish
your creations.
8.12
As Gerald pointed out in his article, graphics are generally poor when
printed on a dot matrix printer. One answer to this is to play to the
technology you are dealing with and keep it simple. Simple, unfilled
drawfiles will usually produce acceptable results, especially if your
ribbon is fairly new. Sprites will often end up looking a mess and
detract from the rest of your document.
8.12
I have also found it to be a false economy to re-ink ribbons. The
savings are not that great and the quality of a re-inked ribbon will
never be as good as that attainable from a brand new one, due to the
wear on the fabric.
8.12
To conclude, if your finances dictate that you can only afford a dot
matrix printer, I would suggest you go for the 24-pin variety. The main
point to ensure is that it is Epson LQ compatible. Having said that, the
obvious choice regarding buying advice along this line would be the
Epson LQ range. Epson have built a good reputation for reliability over
the years and, although the cheaper models are obviously not built to
the ‘tank-like’ standards of the more expensive models, they provide a
dependable choice for the home user.
8.12
Inkjet printers
8.12
If it were possible to extend emotions towards inanimate objects, then
one of the main recipients of sympathy would be the inkjet printer.
Twice, the technology has been launched upon the computer world and on
both occasions it has ended up as the proverbial bridesmaid instead of
the bride. The exception to this is in colour printing which I will deal
with separately.
8.12
The original inkjet printers in the early 80s boasted slightly better
quality than the dot matrix printers of the day, although the dots were
still clearly discernible. The main advantage they held was that they
operated in almost complete silence. Acorn’s first printer in the early
days of the BBC B was a rebadged Olivetti inkjet. The main problems with
these predecessors of the modern day inkjet were twofold. As is still
the case, paper absorbency caused problems with quality, but the main
downfall of the genre was their unreliability. The jets which squirted
the ink were prone to blockage and because of this, they quietly
disappeared from the marketplace to make way for the all conquering dot
matrix.
8.12
The reliability problem has been rectified and the new breed of inkjets
is far superior machines to their early cousins. Gerald has provided a
wealth of technical detail in his article and I will not waste time or
space in repeating that information, not least because I am not equipped
with a high powered microscope. There are a couple of points in his
article however, with which I would take issue.
8.12
Gerald says that Epson inkjets are 300 dpi machines but actually, they
are 360 dpi. The reason for this, I suspect, is similar to why Canon
chose 360 dpi as a standard.
8.12
Hewlett Packard went for 300 dpi because they entered the inkjet arena
from the direction of laser technology which is largely based around 300
dpi and multiples thereof. Having developed the controlling language for
the vast majority of lasers, it made sound commercial sense, when
developing software for an inkjet, to base it around the same
resolution. The savings in programming time alone would have been huge,
as minimal changes would have been required to adapt their existing
software to control inkjet printers.
8.12
Canon, however, entered the inkjet market from the direction of dot
matrix printers which were dominated by the Epson control language,
loosely based around multiples of 120 dpi. They would, therefore, have
already had many of the logic routines written, which could easily be
adapted to 360 dpi. Epson, I am sure, took much the same decision,
although as the third of these three giants to enter the fray, it would
also have occurred to them that being able to boast a higher resolution
than HP was no bad thing from a marketing point of view.
8.12
The second point is that of running costs in comparison with laser
printers. Even ignoring claims made by manufacturers (they all produce
lasers too and have a vested interest in you spending more) and
journalists (who on the whole do not have the time to check
manufacturers claims too closely), it is contrary to my experience and
that of independent groups who have conducted research into printer
costs to claim that inkjets are cheaper to run.
8.12
Three years ago when I decided that the time had come to upgrade from
dot matrix output, I was unsure whether I could afford a laser printer
so looked into the possibility of an inkjet. A couple of people that I
knew were only too happy to demonstrate their machines and provide me
with samples of print quality. Had it not been for the cost of
consumables, I would almost certainly have gone down that road. Far too
much time has passed for me to be able to recall the figures, but those
most surprised at the outcome of a rough price per page calculation
against that of laser printers were the owners of the inkjet printers.
8.12
The main reason for this, I think, is that ink cartridges are affordable
and, although they have to be replaced at relatively frequent intervals,
their price makes this reasonably painless, thereby creating a ‘feel-
good factor’ for the user. Once you budget for their purchase, the
expense quickly becomes accepted. Laser consumables last far longer, yet
their higher price can make them a major purchase in their own right,
depending on which printer you happen to own.
8.12
It is also possible that, due to the frequency of replacing ink
cartridges, the fact that there is a cost per page is more prominent in
the user’s mind, thus making them less likely to print out draft copies
at every stage of development rather than just near the end. I myself am
guilty of printing copious quantities of draft copies to check layout
and graphic positioning, yet have only done so since starting to use a
laser printer. Lasers may encourage bad habits, then, but if used in a
similar way to inkjets, will work out cheaper in the long term.
8.12
(Has anyone actually done any quantitative costing? If so, do let us
know. Ed.)
8.12
Inkjet round up
8.12
Inkjets do not produce such good quality output as laser printers. They
are also less convenient for multiple copies and, to obtain the best
results, you need specially coated paper which adds to the cost of using
them. My personal opinion is that buying an inkjet for monochrome
printing is false economy. Although initial outlay is less, a printer
should be viewed as a long term purchase and as such, a monochrome
inkjet printer will prove to cost more over a couple of years, say, than
would a laser printer. My advice in this area therefore, would be that
anyone considering an inkjet for monochrome printing would do far better
to put the money towards a laser printer. Even those with an occasional
need (or yearning) for colour would, if they can afford it, be better
served by a laser printer coupled with a colour inkjet to add a touch of
colour when required.
8.12
Laser printers
8.12
Although lasers were at one time out of the range of most home users,
this has changed dramatically over the last couple of years. What were
once vague objects of desire are fast becoming almost commonplace in the
home and small office environment.
8.12
Probably the cheapest you will come across are GDI printers. These are
not suitable for Acorn machines and are the PC equivalent of direct
drive printers, requiring Microsoft Windows™ to work. If you own a Risc
PC with PC card, it should be feasible to print your output to file then
copy it to the printer stream through a DOS window within Windows, but
the process of doing this each time would be as convoluted as it sounds
and so does not bear serious consideration. I also stress that I have
not actually tried such a setup, so I cannot guarantee that it would
work at all.
8.12
The entry level is realistically the HP-compatible 300 dpi machine. For
the last three years, I have happily used a Panasonic KX-P4420. While
this particular model has since been superseded, I have never had any
problems with it at all and have found it economical, due to its
internal workings being composed of separates, i.e. drum and toner being
bought as separate items. A friend of mine also owns a KX-P4420 which he
uses as the only printer for an entertainment agency. His output is far
higher than mine and he has also experienced no problems at all.
8.12
I think that although, “more moving parts = more chance of breakdown” is
a valid statement, it is no less true to say that the lower volume of
use that a laser is likely to encounter in the home makes breakdown less
likely than when used for high volume business applications. I take the
view, therefore,  that the home user is better off taking advantage of
the more economical option, at least until such a time as printer
companies put enough toner into the all-in-one cartridges to outlast the
drum. The toner is, after all, the cheapest part of the equation.
8.12
One thing to bear in mind when deciding on a laser printer is the paper
path. With machines that force the paper to first bend one way then the
other en route to the output tray, you are more likely to experience
jams, especially with thicker paper, such as Conqueror. With standard
paper, if you are planning to print double-sided copies, you are also
more likely to have problems with ‘S-path’ printers. In general, the
simpler the paper path, the less curl your documents will display when
printed. If you intend to print envelopes, labels or thin card, it is
also worth checking whether the printer has a straight through path.
8.12
While on this line of thought, I have found that, although printing
envelopes directly sounds like a great idea, it is far quicker and
easier to print address labels and stick them on the envelope. It is
also very much a false economy to use labels other than those made
specifically for laser printers. These may, at first, appear to be
expensive but, in comparison to having a label stuck to the inside of
your printer, they work out very cheap indeed!
8.12
Moving upwards from 300 dpi, the prices of 600 and even 1200 dpi
printers are becoming affordable. I have read good reports of the
Brother HL660 and, although it is a GDI printer, it also comes with HP
emulation, thus allowing its use without Windows. While this contributes
to its higher than normal price for a GDI, it also makes it usable by
Acorn owners. Considering that it is a 600 dpi machine at roughly the
same price level as most 300 dpi printers, and comes fitted with 2Mb of
RAM (expandable to 10Mb), you cannot really go far wrong, even though I
have not yet seen examples of its output first hand. As I have not seen
the printer in action, I am assuming that enough control is available
through the front panel (or !Printers), without having to resort to the
DOS-based software that comes with the printer, to switch between 300
and 600 dpi and select which toner saving mode to use, etc. If so, it
may be worth noting that, in controlled independent tests that simulated
five years use at both 15 and 45 pages per day, this printer’s
predecessor was judged to be amongst the cheapest lasers to own.
8.12
However, I have seen the quality of a 600 dpi HP Laserjet 4+, and it is
noticeably better than that from a standard laser printer. This is most
discernible on close study of curved letters such as ‘o’ and on-line
drawings where the smaller dot size allows for greater smoothing of
jagged edges.
8.12
For much the same price, however, Acorn users can go one step further by
buying Calligraph’s A4 1200 dpi direct drive printer. Having once seen
an example of the quality available from this printer, I was very
impressed, although you would need at least 4Mb of memory to use it at
its highest resolution. More and more Acorn users are falling into this
category though and, with the speed advantages associated with direct
drive printers on the Acorn, I think that this is probably the best
laser printer you are likely to find within its price range.
8.12
Until now, affordable laser printers have largely been based around an
A4 page size. The reason for this is that all the market research for
lasers was conducted in the US. In America, cheap print shops are ten a
penny and, consequently, research appeared to show that there was no
demand for A3 as the extra cost could not be justified. Only recently
did it occur to the printer companies that things might be different in
Europe and, on investigation, they discovered that not only was there an
interest, but also a potentially huge market at the right price. Hewlett
Packard are soon to launch a budget A3 laser printer and will be closely
followed into this market by their competitors. Whether HP’s definition
of the word ‘budget’ coincides with mine remains to be seen. However, if
you are thinking of buying a laser printer, it may be worth keeping an
eye open for developments.
8.12
There are more advantages to A3 than the obvious one of being able to
produce fold-around A4 booklets or A3 posters directly. If you produce
final copy to give to a printer with an A3 facility, it would be
possible to create an A4 image with crop marks that avoided the annoying
all round margin that nearly all current lasers insist on. It also gives
scope for better finishing quality. Currently, when supplying originals
for an A5 booklet, I will print them out at 300 dpi in a large font size
to A4. This means that when the printer has reduced the page to fit an
A5 sheet, the finished article has an effective resolution closer to 600
dpi. If I could do the same except to A3, the end product would have a
resolution close to 1200 dpi. Bearing in mind that the HP A3 printer
will almost certainly have a 600 or 1200 dpi engine, the quality
possible by using this method becomes proportionately higher.
8.12
Calligraph also produce two A3 versions of their 1200 dpi direct drive
printer. Although these are competitively priced in relation to current
competition, they fall under the heading ‘objects of desire’ rather than
being a realistic addition to my want list due to their cost.
8.12
Colour laser printers are available from about £5000 upwards, and while
their quality is generally very good, I am sure not many readers would
be able to justify the initial outlay, let alone the cost of
consumables. Acorn, not surprisingly, do not supply colour laser drivers
with !Printers either, so even if money were no problem, writing your
own printer driver may well prove to be a stumbling block.
8.12
Laser round up
8.12
Given the price of new laser printers, it may be tempting to look
through the small ads. While you can find some remarkable bargains via
this route, it is also true to say that there can be some very expensive
mistakes made if you are not careful. If you intend to follow this path,
do try to buy from someone who lives close enough to you so that you can
see the machine plugged in and working, before parting with your money.
This will also enable you to collect the printer yourself, thus
hopefully avoiding any damage in transit.
8.12
Most will probably choose the security that comes with buying new. I
have had no problems with my Panasonic KX-P4420, so the cheaper of the
two machines which replaced it, the KX-P4410 should prove a good budget
purchase. Panasonic are one of the largest suppliers of laser printers
and their consumables are widely available. The Brother HL660 will allow
you to print using 600 dpi at a small extra cost. For those aiming
slightly higher than the entry level machines, the Calligraph series is
certainly worth closer examination, if you have enough computer memory
to run a direct drive printer.
8.12
Following a brief glance through the Archive price list, I notice that
all of these printers are stocked by NCS. Firstly, I would like to
eliminate any thoughts of bias or ‘advertorial’. I wrote the article
before referring to the list. Secondly, however, knowing Paul’s long-
standing policy of only stocking products that have either been tested
out satisfactorily by NCS or that have been given good reports, I feel
that their inclusion in the price list supports my judgement to some
degree.
8.12
Colour printing
8.12
This area has been covered earlier with relation to dot matrix and laser
colour printing. Spacetech have recently released a dye sublimation
colour printer for £1,000, with Photodesk and a special printer driver.
While the quality from this is better than anything else currently
available for the Acorn range, before beating a track to their door, it
should be considered that copies will cost you £2.50 per page, which
makes debate over the respective running costs of inkjets versus lasers
seem almost petty.
8.12
For the time being, the only serious option for most users who require
colour printing is the inkjet. Gerald covered this area in far greater
depth than I could ever hope to do and I admit to not having much
experience with colour inkjets. Purely on a theoretical level, however,
it would seem that the machine that should be the best is the Epson
Stylus Color, if only because it is capable of a resolution of 720 dpi.
Whether or not there is an Acorn driver to achieve this I do not know,
but if so, it would make logical sense. It is also possible to buy both
black and the three coloured cartridges separately.
8.12
Summary
8.12
For dot matrix printing, I would suggest the Epson LQ series. There is
nothing as compatible as the machine they all strive to copy, and
Epson’s reputation for reliability has not been maintained through luck.
Expect a street price of about £120 for the cheapest, rising to around
£450 for the top of the range model.
8.12
For monochrome inkjet printing, I suggest that you put the money towards
a laser printer, for the reasons explained above.
8.12
For laser printing at the 300 dpi entry level I would go for the
Panasonic KX-P4410. This is available from NCS for £570 inc VAT,
although you may need to upgrade the memory in order to print full pages
of graphics. I believe the price also includes a two year on-site
warranty from Panasonic.
8.12
For laser printing at 600 dpi, it is difficult to beat the Brother
HL660. This is available from NCS for £650 inclusive although, once
again, you will probably find that more memory is necessary for graphics
work, especially at the higher resolution, for which the maximum 10Mb
allowed would not seem unreasonable for an A4-sized sprite.
8.12
For the current ultimate in Acorn A4 laser quality, the Calligraph A4
1200 dpi printer is possibly what you are looking for. This is available
from NCS at £1150 or £1290 for the single and double tray versions,
respectively. As it is a direct drive printer, you will need to check
that your computer has enough memory, before buying.
8.12
For colour printing, Gerald suggested the Canon BJC600ex at £445 through
NCS. The Epson Stylus Color is capable of 720 dpi (using Acorn’s
Printers 1.28 − £5 through Archive) and costs £470 from NCS. u
8.12
C++ Column
8.12
Tony Houghton
8.12
Last month, I introduced the features of C++ which can be used for
improved C programming. This month will start my look at Object Oriented
Programming with C++’s classes.
8.12
Encapsulation
8.12
All programs need data as well as procedures, and some of that data has
to be global as opposed to local. Consider the various ways C allows us
to store, globally, some information about the current screen mode and
the consequences when we need to change the way that data is stored.
Looking at some simplified example header files, the simplest way would
be:
8.12
/* modeinfo.h */
8.12
extern int screen_mode;
8.12
extern int screen_width;
8.12
extern int screen_height;
8.12
/* Read mode and calculate dimensions
8.12
 from VDU variables */
8.12
extern void read_mode_info(void);
8.12
With a bit of experience, you would probably be inclined to tidy this
slightly with a struct. (When declaring a single object of a certain
type, I find it convenient to use capital initials in the class/struct
definition and lower case for the variable itself.)
8.12
/* modeinfo.h */
8.12
struct ModeInfo {{ Style “Main Heading” Off}  int mode;
8.12
  int width;
8.12
  int height;
8.12
};
8.12
extern struct ModeInfo mode_info;
8.12
/* Read mode and calculate dimensions
8.12
 from VDU variables */
8.12
extern void read_mode_info(void);
8.12
In both these cases, you would call read_mode_info() at every mode
change, and every time you wanted to know the mode number, you would
access the variable directly with statements such as x=screen_mode; or
x=mode_info.mode;
8.12
What happens when you want your program to work on a Risc PC? For its
exciting new modes, it uses pointers to mode selector blocks in place of
mode numbers and the data these point to are not guaranteed to remain
valid. This could cause your program to crash, so you would then have to
read the mode number from the operating system every time you needed it.
Rather than calling read_mode_info() every time, you would add a
function int get_mode(void);. In a very long program with many files, it
would be quite a nuisance replacing every screen_mode or mode_info.mode
with read_mode().
8.12
To avoid having to change hundreds of lines of code every time a trivial
implementation detail changes, large projects are developed with small
functions to access global variables instead of accessing the variables
directly. You may have noticed this in Acorn’s C libraries. It also aids
debugging if you know that something can only be accessed by a small
group of related functions. Obviously C++’s inline functions make the
technique far more efficient but there are further advantages in C++. By
using classes, the data can be encapsulated with their associated
functions, and there is greater control over what parts of a program can
access members of a class. A class for modeinfo would look like:
8.12
// modeinfo.h
8.12
class ModeInfo {width ;
8.12
  int height;
8.12
public:
8.12
  void read_info(void);
8.12
  int get_mode(void);
8.12
  int get_width(void)   {width ;}
8.12
  int get_height(void)  {height ;}
8.12
};
8.12
The most obvious change is that the functions are now part of the class
definition, and there is also a new keyword, public. Incidentally, it
seems to be conventional to call functions that read a member
get_<member name>(), and functions that write a member set_<member
name>(). Before explaining classes in more detail, I need to define some
of the terminology.
8.12
Terminology
8.12
A class, analogous to a struct, defines the way an object is
represented. The term class can also be used to cover struct’s and even
union’s. In fact, a struct is now a class in C++, and you can add
functions to struct’s. The only difference is that the members of a
struct are, by default, public and those of a class are private (see
Access control). An object is a variable created from a class (such as
mode_info above). A member is the term for anything which belongs to a
class or object (e.g. mode, read_info()), and a member function is also
known as a method. To call a member function is sometimes referred to as
sending a message to the object.
8.12
There is also the term translation unit. This means a single .c++ or .c
file plus all its headers.
8.12
Reference to members
8.12
Member functions of a class can refer to other members of the class with
just their member name, as width and height are referred to above.
Outside the class, its members must be qualified with the . operator, as
for struct’s − this goes for member functions as well as variables.
8.12
Defining member functions
8.12
Member functions can be defined in two main ways. get_width() and
get_height() are inline functions. By including their definitions with
their declarations, it is unnecessary to use the keyword inline. To
define the functions elsewhere, you use the same syntax for ordinary
functions except that the name is qualified with the class name and the
:: qualifier:
8.12
void ModeInfo::read_info(void)
8.12
{os_readvduvariables or
8.12
  // OS_ReadModeVariable to calculate
8.12
  // dimensions. Actual code is not
8.12
  // needed to make the point.
8.12
}
8.12
int ModeInfo::get_mode(void)
8.12
{r ;
8.12
  r.r[0] = 135;
8.12
  _kernel_swi(6, &r, &r);   // OS_Byte
8.12
 135 reads mode
8.12
  return r.r[0];
8.12
}
8.12
As an alternative to including a method definition in the class
definition (which may make it look cluttered), you can use the ordinary
declaration/definition syntax, but prefix the method definition with
inline. Unlike ordinary inline functions, inline methods do not have
static linkage − all class members must have global linkage.
8.12
Member functions, or methods, behave exactly like ordinary functions in
the way they can take arguments and return values.
8.12
Access control
8.12
There are three types of access that can be applied to members: private,
public and protected. These are the actual keywords that C++ uses.
private members can only be accessed by other members of the same class.
protected members are similar, but they can also be read by any class
which is derived from the base class. I will discuss derived classes
(inheritance) in a future article. public members can be accessed by any
part of the program that has ‘seen’ the class definition.
8.12
One of these keywords followed by a colon specifies that all the
following members have that particular access restriction. You can use
the keywords over again in the same class in any order. For instance,
you may want to start off with some public members, then define some
private inline methods which refer to the first members, then switch
back to some public methods.
8.12
Members in a class start off as private by default, and members in a
struct, default to public. It is common for all member variables to be
private and all member functions to be public. There is usually no
reason for using public member variables − that justifies the lack of
the protection that encapsulation offers − but private methods can be
useful to perform functions that are needed by several public methods,
but not by any other parts of the program.
8.12
As a quick example of how to access class members:
8.12
#include “modeinfo.h”
8.12
ModeInfo mode_info;
8.12
int main()
8.12
{  mode_info.read_info() ;
8.12
          // same syntax for class
8.12
          // methods as for struct
8.12
          // variable members
8.12
  int x = mode_info.width;
8.12
           // error, width is private
8.12
  int y = mode_info.get_height();
8.12
          // OK
8.12
}
8.12
Initialisation
8.12
C++ introduces a new way of initialising objects. Where you would have
written:
8.12
int a = 4;
8.12
you can now write:
8.12
int a(4);
8.12
The new parameter notation is important for initialisation of classes,
but I prefer to stick to the old way (=) where possible. Whilst it is
usually quite easy to distinguish between assignment = and
initialisation =, it is possible, in some cases, for initialisation by
parameter notation to be confused with an actual function call.
8.12
Constructors and destructors
8.12
Sometimes, using an object before it has been initialised can be
disastrous. C++ classes can be provided with constructors which are
guaranteed to be called for each object as it is created. If the object
is a permanent variable, it will be constructed before main() is
executed. Overloading (covered in a later article) allows a class to
have more than one constructor.
8.12
Conversely, you can provide destructors to deallocate memory used by
objects, etc, when they are no longer in use. For a local object, the
destructor is called when it goes out of scope (at the end of a function
or block); for a permanent object it is called during the program’s exit
handler (after executing main() or calling exit(), but not if abort() is
called); for an object created by new, its destructor is called by
delete. When a group of objects goes out of scope simultaneously (e.g.
all global variables), the objects are destructed in the reverse order
from which they were created. Constructors can take arguments, but
destructors can not, and neither return a value. The class listed
overleaf, to implement a ‘safe’ array, will illustrate the above and
more:
8.12
Working from the top, the first new thing is the const member, size. The
only time this can be written to is at the start of construction. Member
array will be used to point to the actual array during construction.
check_subscript() is an example of when a private method is useful. It
checks whether a subscript is within the range of the array.
get_element() and set_element() use this to make sure you cannot cause a
crash by trying to access a part of the array which does not exist.
Actually, as this method has no possible harmful effects, it would be
more useful public, you never know if another part of the program might
want to check subscripts before attempting access. Note the word const
after its declaration. This tells the compiler that it will not alter
anything in the object. This allows you to define whole objects that are
const e.g.
8.12
const Array carray(10);
8.12
Only const methods (apart from constructors and destructors) can be
called for const objects. Similar restrictions apply to volatile − the
compiler needs to know that a method is volatile to avoid applying
optimisations. Constructors and destructors may not be const or
volatile. Constructors are allowed to write members of const objects.
8.12
A method with the same name as its class is its constructor, but if
preceded by a ~, it is its destructor. Note the lack of a type before
the constructor and destructor, both in their declarations and
definitions.
8.12
Now look at the definition of Array’s constructor. After its argument
list (int size), there is a colon followed by an initialisation list
before the body of the function. The initialisation list is where you
initialise const members, and base classes in the case of derived
classes. In fact, any members can be initialised at this point, but
methods cannot be called. If there is a list of initialisers, they must
be separated by commas, not further colons. The order in which members
are initialised depends on the order in which they are originally
declared, not their order in the initialisation list − this allows C++
to ensure they are destructed in the correct order.
8.12
Qualification of the size member by Array:: would not normally be
necessary, but it is needed here to specify the member while its name is
hidden by the argument of the same name. :: is C++’s way of resolving
ambiguities with duplicated variable names. Also, a class name followed
by :: explicitly associates a member with a class − this is the class
qualifier notation.
8.12
A constructor can be used explicitly to create a temporary object e.g.:
8.12
Array a = Array(100);
8.12
return Array(100);
8.12
These statements could cause dangerous side effects, see Caveat below.
8.12
A destructor can be called explicitly as if it were any other method,
but this is rarely useful.
8.12
Classes with constructors taking arguments, but no constructors without
arguments, cannot be included in an array:
8.12
Array array_of_Arrays[10];
8.12
         // Error: Array constructors
8.12
         // need arguments
8.12
A class with any constructor at all cannot be part of a union.
8.12
Caveat
8.12
Consider the following dangerous program:
8.12
// Definition of Array or include etc
8.12
int main()
8.12
{array1(100) ;
8.12
  Array array2 = array1;
8.12
  // ...
8.12
}
8.12
The assignment of array1 to array2 is perfectly valid; instead of
calling array2’s constructor, each member of array1 is copied to the
corresponding member of array2 (memberwise copy), as for a C struct. The
problem occurs when array1 and array2 are destructed. The destructor
will call delete[] for array2’s array member, then do the same for
array1. The trouble is, both objects are sharing the same pointer, so
deleting it twice may cause a crash. This would be resolved by
overloading either the constructor, the operator =, or both.
Furthermore, if array2 had been defined separately before copying from
array1, its data would be left floating around on the free store −
harmless in itself, but inefficient.
8.12
Self reference
8.12
Sometimes it is necessary for an object to be able to pass on some sort
of reference to itself. This is done by the keyword this. In the scope
of a class X, including the scope of its members, this is predefined as:
8.12
X *const this;
8.12
i.e. a const pointer to a non-const object. For const objects this is:
8.12
const X *const this;
8.12
     // const pointer to const object
8.12
Casting this can be allowed to cheat on const. Sometimes, you may have
objects which you want to appear const from the outside, but its members
need to write to some hidden internal data. This can be done by casting
away the const:
8.12
X *non_const_this = (X*) this;
8.12
non_const_this->member = ...
8.12
or by reference (see Archive 8.11):
8.12
X &non_const_this = *((X*) this);
8.12
non_const_this.member = ...
8.12
Static members
8.12
Class members can be declared static. This means that there will only be
one member of that name shared between all objects. Member functions, as
well as variables, can be static. static methods can only access static
members − there is no this pointer for static methods. Do not confuse
static as applied to members with static applied to plain functions and
variables. The latter is for restricting scope to a single translation
unit. All class members have global linkage, so static can only be used
in the definition, not the declaration.
8.12
static member variables are not implicitly created when an object is
created, so they must be defined exactly once. This is done, in the same
way as for methods, by defining the member as if it were an ordinary
variable but prefixing its name with the class name and :: (i.e. the
class qualifier).
8.12
Friends
8.12
A friend of a class is a function, or another class, which can access
the private members of the class that declares it a friend. A friend of
a class is declared by declaring it within the class definition prefixed
by friend. Suppose we needed a function to multiply a vector class with
a matrix class. It cannot be a member of both classes, but it can be a
friend of both. In both class declarations, you would include the line:
8.12
friend vector multiply(const matrix &,
8.12
 const vector &);
8.12
depending on the actual definition of multiply(). The argument types
have to be included, in case of overloading.
8.12
Methods of one class can be friends of another. This is done in the same
way as functions, but with the full method name (qualified by its
class). A class X can be a friend of class Y by including:
8.12
friend class X;
8.12
in Y’s definition. A friend class behaves simply as if all its members
are friends. The keyword class allows classes to be made friends when
they have not yet been defined.
8.12
Friend functions are very useful for RISC OS event handlers. You will
often declare an event handler as a friend of a class and register it
with an object’s pointer as its handle. Within the handler function, its
handle can be cast back to a pointer to class, and operations performed
on the object’s data.
8.12
Nested classes
8.12
Class definitions can be nested within other classes:
8.12
class Array {{ 8.12
    // Implementation of a linked list
8.12
  };
8.12
  LinkedList linked_list;
8.12
  // rest of Array definition
8.12
};
8.12
It is almost always better to define non-trivial classes separately:  a
LinkedList is highly likely to be useful in other parts of the program;
in the example, its definition is only available within Array.  If you
did keep the definition local, you would be more likely to reduce the
two LinkedList expressions to class {... } linked_list;.
8.12
As far as access restrictions are concerned (public, private, etc), the
same rules apply to nested classes as for other members.
8.12
One sort of type that can usefully be defined in a class is an enum.
Suppose the LinkedList can be one of several different types of linked
list and we need a way to differentiate between them:
8.12
class LinkedList {heading Off}
8.12
  enum linkage {single , double};
8.12
// ...
8.12
};
8.12
Outside LinkedList’s scope linkage values can only be referred to by
qualifying them i.e. LinkedList::single or LinkedList::double.
Furthermore, this is only possible if the enum is public, so you will
usually see enum’s in the public part of a class. Nested enum’s are used
frequently in the streams libraries for flag values.
8.12
In fact, any type can be defined within a class and, if it is public,
referred to outside the class by qualifying it with the class name.
8.12
Pointers to members
8.12
Suppose we had a class representing a real life object, holding two
sound samples, an effect for the noise that the object makes and the
spoken name of the object:
8.12
class LifeObject {public: 8.12
  enum sample_type {effect , spoken};
8.12
  void *effect_data;
8.12
  void *spoken_data;
8.12
  void play(void *effect, /* Other data e.g. volume */);
8.12
  // ...
8.12
};
8.12
This is actually a poorly designed class being used in a silly way. The
pointers should be private and the following carried out within the
class. This is just to demonstrate the syntax for pointers to members.
8.12
A pointer to one of the void * members would have the type (called
lo_dt_ptr):
8.12
typedef LifeObject::void *lo_dt_ptr;
8.12
A pointer to the play method would have the type:
8.12
typedef void (LifeObject::*lo_fn_ptr)(void *, /* Other args */);
8.12
and be used as follows:
8.12
void play_a_sample(LifeObject *obj, LifeObject::sample_type which)
8.12
{sample_ptr ;
8.12
  lo_fn_ptr func_ptr = &LifeObject::play;
8.12
  switch (which)
8.12
  {lifeobject::effect: 8.12
      sample_ptr = &LifeObject::effect_data;
8.12
      break;
8.12
    case LifeObject::spoken:
8.12
      sample_ptr = &LifeObject::spoken_data;
8.12
      break;
8.12
  }
8.12
  (obj->*func_ptr)(obj->*sample_ptr, /* ... */);
8.12
  // Parentheses necessary to avoid interpretation as (obj-
>*)(func_ptr(...));
8.12
}
8.12
Note that when assigning to pointer to member the syntax is:
8.12
<pointer> = &<class name>::<member name>;
8.12
The pointer is not bound to any particular object. To use it with an
object, the syntax is:
8.12
<object>.*<pointer to member> or <pointer to object>->*<pointer to
member>
8.12
The member pointed to by a pointer to member can only be used by
specifically attaching the pointer to an object. Casting a pointer to
member to a pointer to a real object or function and then attempting to
use it would probably cause a run-time crash. u
8.12
class Array {size ;
8.12
  int *array;
8.12
  int check_subscript(int subscript) const
8.12
    {&& subscript<size);}
8.12
public:
8.12
  Array(int size);                                 // Constructor
8.12
  ~Array(void)    {delete[] array;}       // Destructor
8.12
  int get_size(void)  {size ;}
8.12
  void set_element(int subscript, int value);
8.12
  int get_element(int subscript) const;
8.12
};
8.12
Array::Array(int size) : Array::size(size)
8.12
{|| (array = new int[size], !array))
8.12
  {raise error
8.12
  }
8.12
}
8.12
void Array::set_element(int subscript, int value)
8.12
{  {// raise error
8.12
  }
8.12
  else array[subscript] = value;
8.12
}
8.12
int Array::get_element(int subscript)
8.12
{  {// raise error
8.12
  }
8.12
  else return array[subscript];
8.12
}
8.12
Array array1;       // Error: no parameter for constructor
8.12
Array array2(100);  // An array of 100 int’s
8.12
void f(void)
8.12
{temp_array(10) ;  // This is constructed every time f() is called
8.12
  // Do something with temp_array
8.12
}
8.12
// temp_array is destructed at the end of f()
8.12
int main()
8.12
{= new Array(200); // Note similar notation for new
8.12
  f();
8.12
  // Do something with new_array and array2
8.12
  delete new_array; // Destructor is called
8.12
}
8.12
// After executing main() array2 is destructed
8.12
Keystroke Column
8.12
Stuart Halliday
8.12
In this, the first of a (hopefully) regular column, I hope to show users
of Keystroke some of the things that can be done with this remarkably
flexible and versatile program.
8.12
For this article, I intend to show how you can make Keystroke choose, at
random, a graphic bitmapped image from a directory and place it onto the
Pinboard as a backdrop every thirty minutes. I’ve chosen to do this for
the Risc PC as it comes supplied, as standard, with directories full of
high quality images, but any Acorn machine running at least RISC OS 3.1
will be able to do this as well.
8.12
You’ll need Keystroke loaded, of course, and the filer must have seen
Keystroke’s associated library !KeysLib as well as the program
!ChangeFSI.
8.12
First choose a blank key combination from the Keystroke main window. I
like to use <alt-Q>, but any will do. This example will take seven
Keystroke actions to complete.
8.12
As I said earlier, the Risc PC comes supplied with lots of images as
JPEG files, so unless you’ve changed its location on your hard disc,
you’ll find them at ‘ADFS::HardDisc4.$.Images.00-49’.
8.12
To get Keystroke to choose from one of the many images in this
directory, it is necessary to use one of the functions called ‘FileList’
from the Keystroke Library.
8.12
So, select the *Command option from Keystroke’s window and type in (as a
single line):
8.12
Run <Keystroke$Lib>.FileList
8.12
 ADFS::HardDisc4.$.Images.00-49
8.12
This will produce a lot of ‘KS$Dir’ variables, starting with ‘KS$Dir1’
to ‘KS$DirXX’ and each variable contains the pathname of the file held
within the ‘00-49’ directory. (Remember to amend the pathname if your
setup is different, and if you’ve not got a Risc PC, just alter the
pathname of this action to point to a directory containing images of
your choice.)
8.12
(Read the ‘List’ file that is within the !KeysLib for more details on
how this and the other functions work.)
8.12
Next, we need to choose one of these variables at random and we do this
by using another !KeyLib function. Click on the ‘New=>’ icon in
Keystroke’s main window, select ‘*Command’, and type in:
8.12
Run <Keystroke$Lib>.Random <KSno>
8.12
This will produce a number from 1 to the value of the FileList variable
‘KSno’, which contains the number of files within the directory pointed
at by FileList.
8.12
So, if there were 52 files in the ‘00-49’ directory, it would set the
variable ‘KS$Rand’ with a value between 1 and 52.
8.12
Now we need to take this random number and select one of the KS$Dir
variables. Click on the ‘New=>’ Keystroke icon, select ‘*Command’, and
type in:
8.12
Set FSIimage KS$Dir<KS$Rand>
8.12
This takes the contents of ‘KS$Rand’, a number from 1 to 52, and places
it next to KS$Dir so it will be of the form KS$Dir1, KS$Dir50, etc, then
places this into the variable FSIimage.
8.12
Click on ‘New=>’ icon, select ‘*Command’, and type in:
8.12
Seteval FSIimage <FSIimage>
8.12
This line takes the contents of ‘FSIimage’, for example ‘KS$Dir23’, and
then the ‘Seteval’ command evaluates this ‘KS$Dir23’ and so extracts the
contents of this variable, which is ‘ADFS::HardDisc4.$.Images.00-
49.sa20’ and stores it back into FSIimage. So we now have the pathname
of the image we want to display on the Pinboard.
8.12
But the Pinboard can’t read JPEG files directly, so we need to use
!ChangeFSI to transform them into sprites first. Luckily, all owners of
Acorn machines get a copy of this very useful graphic translator.
8.12
I’ve decided to place the converted JPEG file into the !Scrap directory
and this is easily done by using another Keystroke action and using the
Wimp$ScrapDir variable.
8.12
So click on the ‘New=>’ icon, select ‘*Command’, and type in:
8.12
Set Pinimage <Wimp$ScrapDir>.Pin
8.12
This sets a pathname within the !Scrap directory and calls the file to
be created ‘Pin’.
8.12
Now we need another action to call !ChangeFSI to convert the JPEG file
for us. !ChangeFSI is one of those rare programs that can be used
without having it on the iconbar. If you want more details on this, read
the ‘FSIinfo’ text file that is held within the !ChangeFSI directory.
8.12
Click on the ‘New=>’ icon, select ‘*Command’, and type in  (as a single
line):
8.12
Run <ChangeFSI$Dir>.ChangeFSI
8.12
 <FSIimage> <Pinimage> 28
8.12
 -noinfo -nomode
8.12
This line runs the ChangeFSI program with a source pathname of
‘FSIimage’ and stores the converted mode 28 sprite, which is 256
colours, in the location of ‘Pinimage’. I’ve chosen mode 28 as everyone,
RiscPC or not, can display this type of sprite. However, if you normally
use a higher number of colours for your screen mode in your Risc PC,
then changing the ‘28’ to ‘S16,90,90’ in the line above will create a
32,000 colour sprite, and the sprite quality will look pretty stunning!
8.12
To place this sprite on your pinboard, you need a last Keystroke action.
So click on the ‘New=>’ icon, select ‘*Command’, and type in:
8.12
Backdrop -scale <Pinimage>
8.12
This places the sprite, which is held at the pathname pointed at by
‘Pinimage’, on the pinboard and scales it up to fill the screen.
8.12
Now move back through each action you’ve defined by clicking on the
‘<=Previous’ icon and highlight the ‘Link’ option in each of the actions
so that they will all act as one big series of actions.
8.12
If you now press the key combination, you should see the backdrop
change!
8.12
As a final touch, if you want the action to be performed every couple of
mintues, go back to the first Keystroke action and highlight the
‘Autoexec’ option in the main window. Then at the Keystroke icon on the
iconbar, bring up the ‘Prefs/Autoexec/minutes’ menu line and type in a
suitable time delay of, say, 1 minute. Don’t forget to click on the menu
line ‘Prefs/Autoexec’ so that it appears ticked. This turns the Autoexec
on; wait a minute and see the backdrop change! Amazing!
8.12
You’ll find a copy of this Keystroke definition on the this month’s
Archive disc and an enhanced one which also randomly chooses between the
directories ‘00-49’ and ‘50-99’ for even more images.
8.12
If you have any queries, or suggestions for subjects on future Keystroke
columns, please write to me at the Quantum Software address (with a
S.A.E. please) or even send some email!
8.12
Stuart Halliday, 35 Pinwood Park, Livingston, EH54 8NN.
([e-mail]) u
8.12
Gerry Dickson
8.12
From the outset, I should make it clear that this article is intended
not so much as a review, as an account of my introduction to the Pocket
Book and some of my experiences with it thereafter. Due to the constant
pressure of work, it has taken almost seven months to complete. The
extended timescale does, however, add another dimension.
8.12
Being the sort of person who likes to be organised, but suffers the
double affliction of innumeracy and absent-mindedness, I have to develop
systems to compensate. I evolved a very efficient paper-based organiser,
the contents of which were tailored to my specific requirements by means
of pages designed on my A420/1 (Risc PCs are a long way off, I’m
afraid). Also, I had misgivings about ‘electronic organisers’. My
reservations centred around (a) the ability to tailor to my requirements
and (b) the ability to access information quickly.
8.12
My interest was roused whilst Christmas shopping (I did say that this
article was a long time in the making!) The Psion 3 caught my attention,
so I read through some of the sales literature then looked up references
to the Pocket Book in Archive. The concept of a pocket-sized computer
(as opposed to an electronic organiser) grabbed me. A concerted effort
from Santa’s helpers enabled me to purchase a 256Kb Pocket Book II from
NCS. My decision to opt for the Pocket Book II was determined by my wish
to support both Acorn and NCS.
8.12
Initial impressions
8.12
NCS delivered the Pocket Book promptly in mid-December; the mains
adapter from Acorn took longer. I negotiated with Santa to allow me
controlled access to my new toy on the grounds that it needed a lot of
keying in − a reasonable argument, I thought. Santa wasn’t convinced but
eventually conceded the point.
8.12
From the start, I was impressed by the power of this little box. It
reminded me of my first encounter, as a complete novice, with my
Archimedes. I was amazed at all of this capacity contained in something
so compact. The screen display is very clear, though I still find it
difficult to find the caret at times. Having relatively small hands, I
find the keyboard is manageable though, in the beginning, I often mis-
typed as a result of being too light on the keys. The key click sound is
useful in this respect. Now, I just mis-type in my usual fashion. Whilst
the Pocket Book fits a jacket pocket nicely, I do think it’s on the
heavy side. The manual is helpful and, being one of these people who
read manuals, is thus far fairly easy to follow. I found the Pocket Book
help-line very useful initially.
8.12
Starting up
8.12
The keying in of information, whilst laborious, was tempered by the
novelty element.
8.12
I began by transferring addresses from my Organiser into Cards. This was
quite straight forward and, in practice, it is very efficient as an
address book. The advantage of ‘electronic’ over ‘paper’ shows itself in
Cards’ ability to update without corrections, search for information and
provide space for additional notes. I did not find DTMF dialling
reliable. This is annoying because, when it works, it is a real boon.
I haven’t had time to investigate this problem.
8.12
PipeDream 4 is the only spreadsheet/database with which I am familiar.
As a result, however, I found that I was able to recognise much of what
Abacus was about. I use it in the main as another form of database for
things like timetables, administrative information etc. I was rather
surprised to discover that there is no provision for password
protection. I believe that a password protection option is available on
the Psion. Password protection remains on one of the menus − perhaps
some kind person might tell me how it can be implemented again. I found
the ‘zoom’ facility very useful in Abacus in allowing one to view a full
week’s timetable on screen. If you haven’t geloused by now, I am a
teacher − a Scottish teacher!
8.12
A frustration with Abacus which I came upon more recently was in
transferring extracts from my PipeDream 4 database into Abacus. A 17Kb
PD4 file results in a 38Kb Abacus file. This may not seem a problem in
these days of megabytes, but, on a 256Kb machine, this can quickly
become problematic. Eventually, I tried a comparison of a small PD4 file
and typing the equivalent information straight into Abacus. I was
surprised to find that the Abacus file was still double in size.
8.12
I found Write to be a surprisingly useful word processor. I use
Publisher extensively but I found Write enjoyable in use. Including this
article, I have used Write to create three documents thus far (all quite
different in character). The spell checker and thesaurus work extremely
well using the keyboard shortcuts; Evaluate’s ability to incorporate
sums is marvellous. However, it is the Outliner which I find
particularly useful in practice. Transferring text to Publisher via the
A-link, for further editing or printing, is simple.
8.12
The ability to incorporate notes, in Write format, into Schedule is,
again, extremely useful, e.g. enabling me to attach notes on a meeting
to its slot in Schedule; the search facility making it relatively easy
to home in on the required note.
8.12
By this stage, the advantage of ‘electronic’ over ‘paper’ is unarguable
− and this is before considering the central application for my
purposes.
8.12
Schedule was, for me, the litmus test. This was the application which
had to equal, or better, my trusty organiser. It is such a feature-
filled package that you really have to plough through the manual in
conjunction with the program.
8.12
I had designed an organiser page which consisted of forty minute slots
(the length of a period in my school). Into this I had incorporated my
timetable of fixed commitments − classes, regular meetings etc. This
enabled me to quickly identify ‘free’ slots which could be used for
interviews, ad hoc meetings, administration etc. This system worked
well, enabling a relatively effective use of my time. The main drawback
consisted of having to print out, cut, punch and date pages a month at a
time. Paper-based organisers have a limited capacity.
8.12
I was delighted to find that Schedule could do all of this and more,
e.g. the To Do facility allows the entire session’s fixed events to be
keyed in all at once, thereafter appearing on the relevant Schedule
pages. Superb! Again, searching for items, or a sequence of items, e.g.
term dates or exam dates, is relatively easy. I could go on, but won’t.
8.12
The main irritant in Schedule, for which I have not yet found a work
around, is a means of switching back and forth from term days
(containing repeat entries of my timetabled commitments) and holidays.
Yes, I can hear all the ‘teacher’s holidays’ quips! At present, I am
keying in my days for one full week, thereafter using the Repeat
facility to block in the remainder of the session. I then go through the
holiday periods deleting the work schedules. Is there a better way?
Please tell me.
8.12
One alarming experience I had with Schedule quite early on was suddenly
being presented with a lack of internal memory. A desperate scan of the
manual revealed the need to regularly compact the Schedule file.
Subsequent to this, I keep the memory usage bar permanently displayed on
screen!
8.12
In use
8.12
The embarrassment of producing this new toy took some getting used to.
For some reason, I found this more difficult than my ‘yuppy’ organiser.
Some colleagues still have palpitations at the sight of a pocket
computer. Clearly ours is not a school in which Pocket Books are a
common sight! This aside, my Pocket Book is now as indispensable as my
old organiser − probably more so.
8.12
Problems
8.12
Problems which have arisen have largely concerned memory. I backup my
Pocket Book files onto PC formatted floppies via the A-link. This works
perfectly well − though I note with interest Julian Midgely’s method of
speeding up data transfer (Archive 8.10 p44). Essentially, the problem
is that 256Kb gets used up surprisingly quickly. Therefore, anyone
considering buying a Pocket Book should opt for the 512Kb version (or
the 1Mb version), if funds allow. On a limited budget, I have thus far
added a 128Kb RAM SSD and a 256Kb Flash SSD. With judicious distribution
of files between the three storage areas on my Pocket Book, and the use
of floppies (providing a fourth form of storage), this has solved my
memory problems for the time being (in more ways than one, if my memory
serves me right). I debated at some length between RAM and Flash SSDs,
capacity, usage and combinations thereof. No doubt this could be the
subject of some debate. I would be interested to hear other views on
this. In the end, as in most things, it comes down to a compromise
between needs, wants and what one is prepared to pay.
8.12
Other concerns which have been noted previously in the Pocket Book
column, and with which I concur, include the flimsy battery cover (I now
tape up the battery cover and the SSD doors), and the keyboard
imprinting on the screen. More serious, however, is a Pocket Book with a
broken neck! I have to report that Pocket Book is off to the Pocket Book
Infirmary suffering a dislocated application bar hinge − take it from
me, this is painful!
8.12
Have Pocket Book will travel
8.12
In April, my Pocket Book accompanied me on a once-in-a-lifetime trip to
Auschwitz-Birkenau, Poland. I was able to record my experiences
virtually as I went along − travelling by train, channel ferry and coach
presented no problems to this little machine. As an idea or an event
presented itself, I could record it there and then. I can now look
forward to developing my notes into an account of my journey. If I dare
say this in Archive, this a God-send to an absent-minded innumerate! u
8.12
CD­ROM Column
8.12
Andrew Flowerdew
8.12
Acorn’s new CD­ROM drives
8.12
The new Acorn A7000 machines have been specifically designed to make
them useful with CD­ROM drives − indeed, you can add one for just £130
inc VAT. These are meant to be truly ‘Plug and Play’ systems − plug in
the drive and RISC OS 3.60 will allow you to use the CD­ROM drive
without any extra software.
8.12
The standard drives are Sony double speed ATAPI drives and I spent some
time playing with an A7000/CD­ROM drive combination. It is a very nice,
compact system and seems quite sprightly in use, although I was in no
position to do any accurate testing. The only problem is that, with a
CD­ROM drive present, you cannot use an expansion card, as the drive
takes up most of the space in the box.
8.12
“What is an ATAPI CD­ROM drive?” I hear you ask. Well, Acorn see ATAPI
as an ‘emerging standard’ − in other words, a standard which, like most
standards in the computer industry, is not really a standard but may be
getting there. ATAPI stands for AT Attachment Packet Interface and was
proposed by drive maker Western Digital. It is a system designed to
allow cheap peripherals to be fitted onto existing IDE or EIDE
interfaces, without the need for extra hardware.
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Although the first Acorn drives are double speed drives, there are
already drives on the PC market which are quad speed and sold for
between £140 and £220 inc VAT. This follows the trend with SCSI CD­ROM
drives, where most manufacturers are now beginning to standardise on
quad speed. So, with any luck and with a little bit of programming from
Acorn and its third party developers, we may well see a new crop of
‘cheap’ ATAPI drives appearing on the Acorn market. However, a word of
warning, don’t rush out and buy any old ATAPI drive − take heed of the
Acorn phrase, ‘an emerging standard’. Not all ATAPI devices will work
with Acorn’s version of the ATAPI standard and, at the moment, only RISC
OS 3.60 is designed to accept ATAPI drives.
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More fun with the PC card
8.12
There has been a fair bit of correspondence about the PC card since I
wrote the last column. In general, most comments can be summed up by the
phrase ‘It’s good but it could be better’.
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This is where I nail my colours firmly to the fence! Yes, the PC card
could be better, but look at its price, and then think that it has to
cope with an operating system like Windows. Put the added complication
of users who are used to a really nice operating system like RISC OS,
and you have a recipe for confusion amongst the average user.
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What are Acorn to do? Most of my problems with Windows CD­ROMs have been
down to software problems and most of these will be solved as more
people report bugs. So, with any luck, within six months, we should have
software drivers which solve most of the problems.
8.12
The other criticism is that, to run most multimedia CD­ROMs, you need a
better specification than the basic 5Mb Risc PC. True, you are better
off with a 9Mb machine and a larger hard drive, but this is also true of
a PC clone. Yes, companies advertise ‘Multimedia PCs’ for silly prices,
but if you look at the specs, and buy from a half-way reputable company,
you will certainly have to upgrade some part of the system to make it
run multimedia CD­ROMs easily. However, it is still true that a Risc PC
set up to run Windows CD­ROMs is going to cost several hundred pounds
more than a comparable PC. Quality costs, and if you buy the Acorn, you
get quality and ease of use − that’s why I buy Mazda cars − they cost a
little more, but they are reliable and I like the way they let me drive.
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New CD­ROM formats
8.12
There have been several bits of news filtering through about proposed
new CD­ROM formats, and I know there is always more than a little
concern about our kit becoming obsolete. However, we should always
remember that software developers have a vested interest in selling to
the market where the vast majority of drives are found. Those drives are
the double and quad speed drives that we are buying now and these drives
will remain the dominant force in the market for several more years to
come, by which time you should be ready to upgrade anyway.
8.12
The new formats are designed to allow producers to put much more data on
a single CD­ROM. To be precise, they allow the whole of a feature film
to be stored on a single disc. The formats, one supported by Philips and
Sony, and one supported by Hitachi, Pioneer, Toshiba and several others,
look as if they will start an all-out war between the major hardware
manufacturers − a little like the VHS, Betamax war.
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The Philips/Sony standard is single-sided, with 3.7Gb per layer, with up
to 8 layers being theoretically possible. The Hitachi/Toshiba standard
is double-sided with 5Gb per side. As with the VHS/Betamax war, it will
be the availability of software which will decide the winner. That is,
if it gets that far − the major players in the IT world nowadays seem to
be moving towards cooperation rather than confrontation, and it may be
that we will end up with a compromise format with some of each standard
included.
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So, should you hang on before buying your next (first) CD­ROM drive, in
the hope that you will get one of the new high capacity formats? No! It
will be several years before these formats come to the market and, even
then, it may be several more before a clear standard, and the software
to support it, will be established.
8.12
As always, you can contact me via Archive or c/o DCPS, Cranbrook, Kent,
TN17 3NP or via e-mail on [e-mail]. u
8.12
Puzzle Corner
8.12
Colin Singleton
8.12
It is an occupational hazard for a puzzle-setter that someone may find a
better solution than mine! For example...
8.12
(22) Differences
8.12
Last month, I allowed myself a note of caution in declaring the best
solution to be one requiring 36 cycles of the difference operation. The
day after I posted my copy to Paul, Nick Craig-Wood’s entry arrived,
with an order-37 solution − closely followed by two more from Dr Riha.
These are (0, 121415, 344732, 755476) (1, 121416, 344733, 755477) and
(1, 410745, 634062, 755477). It is, I think, no coincidence that each of
these lead to my ‘solution’ (121415, 223317, 410744, 755476) after one
operation. I now declare these to be the ‘best’ solutions − unless, of
course, you know better ... ! Nick Craig-Wood wins the prize.
8.12
(23−25) Similarities − Rhymes − Pythagorean fractions
8.12
No major problems here, although one reader submitted x = 60, y = 45,
z = 36 for the Fractions puzzle, without realising that these can each
be divided by three to give a ‘simpler’ solution. Some variations on the
root words fashion and cushion are allowed for the Rhymes puzzle, though
dictionaries seem to disagree. Pin-cushion is not allowed, because it is
hyphenated. Readers were agreed that, as one put it, “There’s nonth that
rhymes with month”! The prize goes to Clive Semmens, of Ely.
8.12
(26) Race tracks
8.12
T H O’Beirne, in his book Puzzles and Paradoxes, gives a solution
technique which works when the number of posts is one more than a prime
number, which is true of our puzzle. Unfortunately, it only works easily
when the circuit-length is prime, which is true of the example I gave,
but not of the puzzle I asked you to solve! Computerised trial and error
is probably as good a technique as any in this case − it could be a good
number-crunching exercise to try out your new ARM7 machine! Given three
of the posts in positions 0, 1 & 3, there is only one solution, shown in
the diagram.
8.12
Solutions can always be found if the number of posts is one more than a
prime, or one more than any power of a prime, but probably not in any
other cases. There is one fundamental solution for 3 posts, two for 4,
one for 5, five for 6, six for 8, four for 9, and six for 10 posts.
There are no solutions for 7 or 11 posts.
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(27) Overlapping squares
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Extend the sides of the large square, as shown. This dissects the small
square into four identical pieces. The shaded region is ¼ of the small
square, i.e. 4 square units.
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(28) Harems
8.12
Choosing whether or not to have a child, even if the ‘choice’ is
dictated by law, does not change the balance of the sexes − it is one-
to-one. Since every family includes just one boy, the average family
size is two. You can prove this by calculating the probabilities of
families of different sizes. It is now possible (but highly immoral!) to
change the population sex ratio by deciding on an abortion after
determining the sex of an unborn child − but that was not the question.
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(29) Back to basics
8.12
The next two numbers in the series 10, 11, 12, 13, 14, 15, 16, 17, 20,
22, 24, 31, 100 are 121 & 10000. The clue is in the question − the
number sixteen has been written in bases 16, 15, 14 ... 2.
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This month’s prize puzzle...
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(30) Rectangles
8.12
For this geometrical puzzle, you are required to dissect a rectangle
into a number of smaller rectangles. The side-lengths of the rectangles
are all integers, and no two rectangles have a common side-length. No
rectangle is square. What is the smallest possible area for the outer
rectangle? The diagram shows a rather silly first attempt − the lengths
1, 3, 4 & 7 each occur in two different rectangles.
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This month’s prize quickies...
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(31) Tennis balls
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How many tennis balls are required to build a square-based pyramid, if
the total number of balls is a perfect square?
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(32) 27 digits
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A 27-digit number includes the digits 1 to 9 three times each. There is
just one digit between the first two 1s, and one digit between the last
two 1s. There are just two digits between the first two 2s, and two
digits between the last two 2s. And so on ... . What is the number?
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(33) Loony PAYE
8.12
The Unofficial Loony Party propose that income should be taxed at a
percentage equal to the gross pay in pounds per day. What is the optimum
income?
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Comments and solutions
8.12
Please send comments, contributions and solutions to me at 41 St Quentin
Drive, Sheffield, S17 4PN. Solutions by Friday 8th September, please. u
8.12
Why Use a Pocket Book?
8.12
Up-Slicing a Risc PC
8.12
Eric Ayers
8.12
(Well, what would you call “adding more slices to a Risc PC”?) I offer
some comments, based on my experiences, in the hope that they may be of
use to others contemplating similar action. However, do not expect the
operation to improve your cash flow!
8.12
My ACB 45 already had two slices with four podule slots, and options
available were to expand to three slices with six slots or four slices
with eight slots − I chose the latter. Apart from the extra case slices
themselves, together with special long fixing bolts, you get an
additional power unit and a new backplane with eight podule slots to
replace the existing 4-slot backplane. If you go for the 6­slot option,
you get one slice and the same new backplane, with the top two slots
literally chopped off. For single-slice machines, there is also an
option to upgrade to two slices, but I have no detailed information on
it. I ordered the bits from NCS, and they arrived in the usual very
generous packages with Atomwide written all over them, and included very
clear fitting instructions with explicit diagrams.
8.12
Slices come in two forms − ‘open’ and ‘closed’. The former have a cutout
for a floppy drive in the front, whether you want it or not, and also
extra clearance internally for the additional power pack. The latter
sits on top of the existing power pack, so it is important to assemble
the open and closed slices in the right order, as instructed. Once the
top of the computer has been removed, it is very simple to pile on the
new slices, and to insert the new long bolts. The new power pack is fed
by a supplied cable from the socket originally intended for the monitor,
and its own switch is set permanently on, so that both power units are
controlled from the mains switch on the front of the computer. A new
cable is supplied to feed the monitor independently from an external
13­Amp socket.
8.12
Before replacing the lid, the old backplane must be removed and the new
one inserted. All podules must, of course, be withdrawn first. The top
four slots on the new backplane are to be supplied from the second power
unit, so you have to fish out the right lead from the latter and plug it
into a socket in the upper half of the backplane. This involves some
juggling with the slices to gain access, unless you have double-jointed
fingers. The backplane then has to be pushed home firmly, but not
forcefully, into the connector on the computer motherboard. I was none
too sure what constituted ‘forcefully’, but I could not get the
backplane to go home. I eventually discovered that the power socket
mentioned above was fouling part of the case slice. I saw no way of
avoiding this, and had to cut away a small, and I hope inessential, part
of the internal web of the slice. (We’re not quite sure what happened,
but there shouldn’t really be a problem here. If anyone else finds a
difficulty, just ring Atomwide. Ed.)
8.12
I was not adding any further devices so had a mass of extra power
connecting cables to stow safely before replacing the lid. With some
trepidation, I switched on, and breathed a sigh of relief when I got a
normal desktop. *Podules revealed eight (empty) podule slots, so the
next job was to start filling these again. I had installed a CD-ROM
drive and a Cumana SCSI 2 card, so the latter was the first to go in, to
the bottom slot (0) to get the advantage of DMA. Being impatient, I then
plugged in most of my other podules. A repeat of *Podules revealed them
all as present and recognised. Then the troubles started.
8.12
I had put a couple of podules in the upper set of slots (i.e. the new,
expanded ones). Though recognised, these podules refused to run,
returning an error message “Module ... could not be found”. Transferred
to the lower (original) set of slots, they performed normally. After
much gnashing of teeth and a ‘phone call to Matthew Hunter at NCS, the
reason was explained. Apparently, Acorn’s guidelines for writing podule
ROMs have not caught up with the possibility of eight slots, and most
podules will need a ROM update.
8.12
One podule I had was Computer Concepts’ Scanlight Plus. They recognised
the problem and offered an update for £11.75 inclusive, so I bit the
bullet and sent off my cheque. Back came an update disc − not a solution
to the problem. Another ‘phone call resulted in profuse apologies and
the new ROM by first class post. This did the trick and the podule
functioned perfectly in slot 7. The next move would obviously be to
chase up the suppliers of the other podules, but another snag reared its
ugly head.
8.12
I tried to access the CD-ROM drive and a hard disc on the SCSI card.
They appeared to respond, but produced masses of errors, with the hard
disc eventually reporting “broken directory” and the loss of all the
files on it. Fortunately, I had fully backed it up to an IDE hard disc,
but the net result was to make both devices unusable. In despair, I
ripped out all the podules except SCSI2, and the latter then functioned
perfectly. Restoring podules one at a time, even into the lower slots,
re-introduced the errors − only the CC Scanlight podule was accepted
without error. I have to confess that this behaviour is still not
accounted for, and any helpful suggestions would be gratefully received.
I did ring the changes on terminator resistors on the SCSI bus, but to
no avail.
8.12
Another of my podules is for Irlam’s hand colour scanner − this will not
run in upper slots, and also upsets SCSI. I have been in touch with them
and they have promised to look into the ROM specification, and also the
SCSI 2 incompatibility. Hopefully, a solution will eventually be found
but, at present, I am getting no benefit from my ‘Up­Slicing’ apart from
a larger box which blocks out more of the light from the window and a
second hefty power pack which is running just one podule!
8.12
Going to eight podule slots is certainly revealing problems that were
not obvious when four was the maximum. It’s one of these situations
where, potentially, everyone could blame everyone else... “It’s not my
podule that’s at fault.” The majority of podules around at the moment
were designed and tested on A5000s and not Risc PCs, let alone 8-slot
Risc PCs, so it’s not surprising there are problems with interaction.
What Atomwide are, very helpfully, doing is to create a database of
known problems in terms of ‘podule A conflicts with podule B unless
podule B has its ROM upgraded to such-and-such’. So if you are having
similar problems, and especially if you are willing to help by trying
out various permutations and combinations, give Atomwide a ring. (One
suggestion for Eric, and others with a SCSI 2 card, is to switch the
block-mode off and also, possibly, the synchronous mode.) Ed. u
8.12