Although the SCART connector can support separate Red, Green
and Blue lines, they are not always implemented.
If your Television sports a true SCART compatible connector,
the RGB signals from the A600 should drive it perfectly, and
as you know give a much better display than with blurry colour
composite.
Unfortunately you can't get a picture, so therefore your TV
is crap. Sorry.
Explode
I own an A600, and I'm having difficulties with the virus
checker program given away on the CU coverdisk. I have
dragged the icon into my Workbench Startup drawer, but when
I reboot I get the message 'Need explode library v14+'. Can
you help?
Tracey Foulsham, Birmingham.
This letter sums up the dozens of similar queries regarding
the dreaded exploding library, and the reply will hopefully
help everyone to sort out their problem.
When the Amiga boots, it likes everything to be in place. It
likes the AmigaDOS commands to live in the C directory, and
the fonts to be in the FONTS directory. It also likes
libraries to be in the LIBS directory.
A library is a special piece of code which offers some
common features to programs. In this case, the virus checker
program needs some compression and decompression routines,
and these live in the explode.library.
When you boot from the coverdisk, LIBS: is set to point
to the LIBS drawer on the coverdisk, which contains the
explode library. When you boot from your Workbench, LIBS:
is set to point to the LIBS drawer on the Workbench - which
probably doesn't contain the explode library.
So when you copy the Virus checker program, you also need to
copy the library, Some programs come with a utility called
something like 'install library' which will automatically
copy across any required libraries, but here is how to do it
manually.
1. Boot from your Workbench in the normal way.
2. Open a SHELL window.
3. Put the coverdisk in the drive.
4. Enter COPY df0:libs/explode.library to RAM:
This will make a copy of the explode library in the Ram
disk.
5. Put your Workbench disk back into the drive.
6. Enter COPY RAM:explode.library to LIBS:
This will insert the library into the correct drawer.
COBOL
I'm presently learning the COBOL programming language for my
college course but am in need of a COBOL compiler for the
Amiga. I've searched the PD libraries but with no luck: can
you help?
James Deadman, Welling, Kent.
Commiserations on your unfortunate situation. I had to use
COBOL as part of my so-called education, and what a waste of
my life it was. I recommend you change colleges to one
which won't waste your time with this crappy language, but
teaches something useful (such as C) instead. In my case,
this meant a change from the Science to Engineering
faculties. In case you can't manage this, you'll need to
get a PC emulator (software should suffice) and a PC COBOL
compiler.
DTP
For some time now I have been looking for a DTP package
which includes powerful features whilst also being easy to
use. Presently I do not own any DTP programs, but I want to
produce high quality work.
Andrew Chang, Wimbledon, London
You missed out several important facts, Andrew. How much do
you want to spend? Do you have a printer, or will you be
using a bureaux? If as I suspect you want to dabble your
toes in the murky waters of desktop publishing before
plunging in headlong, I suggest you get hold of The
Publisher, which was reviewed in the December 1993 issue.
It costs about £30, and at this price its only competition
is the equally adequate PageSetter from Gold Disk. Check
out the adverts in this issue for prices, as they tend to
change rather quickly.
Maths
Ever since I've had my Amiga I've been interested in
graphics based around mathematics. You may not believe
this, but there is actually a limit to the amount of
pictures that you can display on the screen.
I have devised a formula to actually calculate the number of
screens possible in a screen mode such as low resolution, 32
colours: colours to the power of the number of pixels.
It's not a very complex formula I must admit, but it works.
For example, if you took a screen of 320 by 256 (81,920)
stored in 4096 colours (HAM mode) the number of different
screens you could produce would be... far to large to print
here, but I can say that the number consists of exactly
295,925 digits. When you consider that 1 page of CU Amiga
contains approximately 6400 characters, it would take 462
pages of CU to write this number down (about two full
issues). However, this number does cover every single
picture seen in any art package or game, ranging from a
screenshot of Populus 2 to a Vista Pro 3 image, to a purple
dot in the corner of the screen in Deluxe Paint.
Thanks for your time.
Daniel White, Walsall.
Thank you Daniel for trusting us with your formula. I trust
you have written a program which will randomly fill the
screen with dots, because eventually you'll get a picture of
your own face. Or the Mona Lisa. Or an image of the Earth
as seen from the Moon. Or a full-colour image from the
inside of my stomach. In fact, given a fast enough computer
we could use your theory to generate the screen shots for
the January 1995 issue, which would save us the trouble of
taking them at the time.
Hard drive and memory
I have recently bought an 80Mb hard drive for mr 2Mb A600
which I have installed myself. After the computer has been
switched on the screen flickers quite badly for the first
half hour or so, almost as though it was warming up. Is this
the case, and is it harmful to my Amiga?
Also, the drive came in two partitions: a 75Mb partition and
a bootable 5Mb partition for Workbench. Is there anyway I
can enlarge the Workbench partition?
Finally, a friend told me that there is a 2Mb upgrade
available for the trapdoor. Is this true? I've never seen
them advertised anywhere, so I through I'd check with you.
Would a PCMCIA card work with programs such as OctaMED and
CineMorph? Is there anyway to accelerate the A600, as
morphing takes ages.
Dave Park, Letchworth, Herts.
Your screen flickering problem could be power related.
Perhaps the standard PSU hasn't enough juice and is
struggling. Failing that, either the hard drive or the Amiga
is broken - it's certainly not normal behavior. Early Amiga
modulators have been known to flicker between colour and
monochrome, but recent ones should be ok.
The HDTools program has an option screen dedicated to making
and altering partitions. You should have no problems
resizing your drive (10Mb for Workbench is more useful) and
if you make sure the tick is in the bootable requestor
you'll be alright. Before you start remember to back up all
your data, as re-partitioning a drive will destroy it's
contents.
I haven't heard of any memory expansion for the A600 other
than the 1Mb card that fits into the trapdoor, which gives
the A600 a total of 2Mb of chip ram. Memory added to the
PCMCIA card slot is not chip ram, but it will still be used
my the system. For example, the OctaMed program will
automatically load into the PCMCIA memory, leaving more of
your chip ram for samples.
Currently, the only way to accelerate an A600 is to throw
it out of a window. Remember if you upgraded it to a A1200,
you could take the hard drive with you.
Keymaps
Dear Cu Amiga, I can't set the Keymap of my Amiga to GB and
I get a $ when I type a £.
Lots of people, Everywhere.
Ok, I thought this was simple until I had to do it myself
again recently on a Workbench 3 system. Assuming you have
your entire Workbench available on a hard disk, you must set
the following:
Prefs/locale/Country to United Kingdom
Prefs/locale/Preferred Language to English
and select SAVE.
Then set the following:
Prefs/Input/Keyboard type to British
and select SAVE.
Next time you open a Shell, the keymap should be set
properly.
Now, if you are using a floppy only system you will need to
make sure that your boot disk contains the file 'gb' in the
DEVS:keymaps directory. If it's not there, you'll need to
copy it across from the storage directory.
Floppy linking
I'm hoping to upgrade my Amiga 500 to an Amiga 1200,
possibly through some sort part exchange deal. However, the
saving I'd make is only about £60 - the price of an external
drive.
Is it possible to use the internal drive from the A500 as an
external drive on the A1200, either by linking the machines
or taking the drive out and rewiring it? If possible I'd
like to keep my A500 in one part, so can I use the drive
from any other machines? In fact, are there any parts from
old Amigas that can be used with the A1200?
Ben Hollis, Norwich, Norfolk
Using the Pd program Parnet (see next month's DIY section
for full details) you can connect the A500 and A1200
together, and the A1200 can access the A500's floppy drive.
And vice versa.
Unfortunately it isn't possible to use an internal drive as
an external Amiga drive a some extra electronics are
required. The same goes for any naked drive mechanism you
might see, so stick to Amiga specific drives.
As for cannabolising the A500 for parts - again, I'm afraid
not. The mouse is probably the only part of the system that
could be used as the A1200 motherboard and chips are several
years more advanced than the trusty old A500, and nothing
would be any use.
Programming
I'm 1, and I wish to write games software for a living on
the Amiga when I'm older, so I thought I'd start learning
now.
I already know how to use AMOS, so I want to get DevPac and
learn 680x0 assembly language - or I did until I saw a line
in CU Amiga that said C was more powerful than machine code.
Could you tell me what language the games companies use, and
what books and software I need?
Lenny, Worksop
Which language is more powerful is open to debate. For pure
speed, you can't beat raw assembly language because that's
what every other language is eventually translated into.
On the other hand, C offers a lot of support for data
structures and function calling - ideal for larger programs
and making use of the operating system. Interestingly, a
good C compiler will produce code almost as good a
hand-written assembler.
Most games companies use assembler, but more are turning
towards C because as games become more and more complicated, it
makes sense to write all the game logic in C and keep the
assembler for the ultra-speed critical graphics code.
My advice to you would be to learn C first because the
principles involved are more important than knowing the
Motorola instruction set inside out. Anyone who can program
can learn how to code in assembler in a day - it takes a lot
longer to learn how to program in the first place, and
longer still to learn how to program the Amiga.
A1200 Concerns
I'm considering buying an Amiga 1200, and have some
questions:
1. How do I know if there is a virus on a hard disk and how
do I get rid of it? Does it mean that everything has to be
reloaded, including all of Workbench?
2. How do I know if programs bought of floppy disk will
install onto a hard drive?
3. I have loads of Spectrum games on tape, and I notice that
there is a Spectrum emulator in the Public Domain. How do I
connect the cassette recorder to the Amiga? What do you
think the chances are of getting the games working?
4. By the way, who is Fred Fish? Am I the only one not in of
this?
Robert Pickering, Denbigh, Clwyd.
I hope you decide to go ahead and get a A1200, and here are
some answers:
1. A public domain program such as VirusChecker will look
through the files on the disk, and if it finds a virus it
will delete the suspect file. You don't have to install
everything again.
2. The box the game comes is will usually have a sticker on
it, but the best way is to check the reviews in CU as we'll
always say if a game can be installed or not.
3. The Spectrum emulator can load games from cassette tape
by means of any normal tape recorder connected to an Amiga
sound digitiser (sampler). As long as the game doesn't make
use of any strange copy protection methods, nearly all
Spectrum software works fine: I've been playing the classic
game Thrust with the emulator on my A4000 quite a bit. Well,
until I bought Frontier.
4. No, you are not alone in your ignorance about Fred Fish.
At the recent so-called 'meeting of minds', practically all
of the Amiga developers present had no idea about the
identity Fred Fish. To me this says a lot about the
developers - they treat the Amiga simply as a games console
and have no interest in the Amiga community at large.
There's no great mystery about Mr Fish - Fred is the guy who
collects all the Amiga PD to release as his 'Fish Disk'. He
has so much software now that he's releasing it only on
CD-ROM, so buy the last CDTV in the shop now.
SWAPPING
I often swap pictures on disk between my Dad's PC and my
Amiga by using CrossDos to load the PC-format disks on the
Amiga Workbench.
My Dad also has an Apple Mac in work - is there anyway I can
get the Amiga to load these sort of disks? There is a
colour scanner connected the Apple and it would be great to
load the pictures into Deluxe Paint.
Colin Turner, London
The trick is not to get the Amiga to think like a Mac, but
to get the Mac to think like a PC. Confused? Don't worry -
the Apple Mac uses a very strange way of storing data on
floppy disks, but with the Mac program Apple File Exchange
which all Macs come with, it can read and write to ordinary
PC format disks.
As you know the Amiga can read PC disks through CrossDOS
(included with all WB3 machines) so the only remaining
problem is the file format. A common Mac file format is
TIFF, which is totally incompatible with Amiga's own IFF.
However, there are some programs in the Public Domain which
will convert files for you. Some Mac programs also support
JPEG which is a great way of squeezing large 24bit colour
files onto a single floppy.
QUESTIONS
I have a number of questions weighing heavily:
1. Why do you need a memory expansion to increase the speed on an A1200?
2. Would it be better to fit a Power Computing PC1200-4 or a Microbotics MBX1200Z with the same amount of memory?
3. Do I really need an FPU if all I do is play games?
4. Does the running speed of the CD32 match that of an A1200 fitted with extra memory?
5. Is the access time from a CD-ROM faster than from hard drive?
6. Assuming the answer to question 4 is yes, if I bought the a CD-ROM drive for my A1200 would I no longer need the memory expansions?
7. Is it possible to use normal joysticks with the CD32?
B.A. Doherty, Winsford, Cheshire
Here are some equally weighty answers:
1. The A1200 comes with 2Mb of chip memory as standard. Chip memory is shared between the CPU (the Motorola 68020) and the custom chips which produce graphics and sound. Because of this shared arrangement, the CPU takes slightly longer than normal to access the memory, and this slows the computer down slightly. When extra memory is added via the trapdoor, the CPU has immediate access and can therefore run at full speed - this explains why it is called 'fast memory'.
2. Depends on which you one like best. Seriously though, we're doing a complete round up of all A1200 peripherals soon which should answer your question.
3. No, if you only play games the extra expense of an FPU is wasted. It does make sense to buy a memory board which could theoretically support an FPU in case you change you mind, and get hooked on graphics or sound software.
4. No, as the CD32 has only (hah! only!) 2Mb of chip ram, it runs at the same speed as an unexpanded A1200. However, the CD32 has an extra chip (Akiko) which can speed up some graphics operations ever so slightly.
5. No, a hard drive is much faster. A double speed CD-ROM (like the one fitted to the CD32) will shift data at about 300K a second: a lot slower than a good hard drive. With good programming, CD access can appear a lot faster - certainly fast enough to spool graphics and sound data directly from disk.
6. The question is: if you bought a CD-ROM drive for the A1200, where would you stick your memory expansion. This is a question which can only be resolved when Commodore release details on the CD-ROM drive.
7. Yes, although the supplied joypads are better because they support more buttons - probably only for stupid martial arts beat-em-ups. Now I'm going back to Commander Kennedy, somewhere in the Groombridge system...
--- end ---
TEAM TALK
John has:
* Not been flying his kite because it is too cold,
* Trying not to fall of his motorbike on the icy bits,
* Walking around with his fingers crossed to hear if he will graduate,
* Coughing and sneezing a lot,
* Picking dead mice off his garden path,
* Answering an ex-CU Amiga technical editor's questions about technical stuff and helping him get off with his girlie (she likes being spanked apparently),
* Playing Elite II too much and neglecting his own girlfriend,
* Lusting after a 68040 accelerator (sad :-( ),
* Playing hard to get with Lisa C. on the telephone,
* Teaching his brother how to pass the driving test (he failed :-),
* Trying to find time to write the best Amiga driving game ever.
