VGA Spectrum 1/UGASpectrum.cdr/utility/grafwk41.exe/DRIVERS.DOC

Text File | 1990-06-06 | 10KB | 199 lines

Dot matrix printer drivers for Graphic Workshop
_______________________________________________

This version of Graphic Workshop includes the following dot
matrix printer drivers. All the supplied drivers print to LPT1.
You can redirect this with the DOS MODE command. If you write a
custom driver you can have it print to any port you like.

Note that while the external printer driver facility was
implemented in Graphic Workshop to support dot matrix printers,
you can write a driver to support pretty well any output device,
including film recorders, FAX boards and so on.

This release of Graphic Workshop is a bit thin on specialized
drivers... yes, two is a bit thin. We're working on borrowing
some of the popular printers to write drivers for them.

EPSNFX80.PDR    This is a driver for the generic Epson FX-80
                modes. It will work with many dot matrix
                printers, although with far less resolution than
                some newer printers can manage.

EPSNFX80.ASM    This is the source code for the generic Epson FX-
                80 driver, for use as a starting point in writing
                your own custom driver. If you come up with a
                printer driver of your own, please send us the
                source and we'll include it in future releases of
                Graphic Workshop with suitable credit.

GEMINI.PDR    This is a driver for the 480 dot wide mode of the
                arcane Star Micronics Gemini 10X. The output from
                this printer is pretty ugly. The double
                resolution graphics mode of the Gemini 10X is a
                bit narrow, and pictures come out with badly
                distorted aspect ratios, so we didn't use this
                mode.

Registered users of Graphic Workshop wishing to write their own
drivers are welcome to whatever help we can supply. We can't
teach you to program in assembler over the phone, but we can
probably help you with basic questions and suggest ways around
any problems you encounter.


Super VGA card drivers for Graphic Workshop
___________________________________________

NOTE: As of version 2.4 of Graphic Workshop, the internal
structure of the super VGA drivers changed a bit. The old drivers
will no longer work with GWS.EXE. New versions of all the current
drivers are included with this release... delete your old
drivers.

MORE NOTES: As of version 2.7, all the drivers were changed
slightly. This involved using a slightly different technique for
setting the VGA palette to make palette adjustments from within
the VGA 256 colour mode look nicer. Older drivers... written after
version 2.4 of Graphic Workshop... will still work, but you'll
see a bit of screen trash when you adjust the VGA palette.

This version of Graphic Workshop includes the following drivers:

TRIDENT.DRV    This is a driver for the Trident VGA graphic
                cards. It drives the card in its 640 by 400, 256
                colour mode, and will work with cards having 256
                kilobytes or more of onboard memory. We
                originally found the Trident card this driver was
                developed on in a Sun Moon Star 386SX we were
                loaned. It turned out that the monitor provided
                with this computer would not sync in the 640 by
                400 256 colour mode, even though the card was
                doing fine. If you have this system, you probably
                won't be able to use this driver unless you
                spring for a multisync monitor.

VIDEO7.DRV    This is a driver for the Headland Technologies
                Video Seven VRAM and Video Seven 1024i cards. It
                supports the 640 by 480 line 256-colour mode. It
                uses the standard VGA and EGA 16-colour and
                monochrome modes... we decided not to implement
                the 1024 by 768 16-colour mode. There are very
                few 16-colour images around which could take
                advantage of this mode, but there are a lot of
                monitors which cannot.

PARAPLUS.DRV    This is a full featured driver for the Western
                Digital Paradise Plus card. This driver also
                works with the Dell Super VGA card, which is
                actually a Paradise 16-bit card.

DELLVGA.DRV    This is a version of PARAPLUS.DRV, above. It has
                been modified not to use the 800 by 600 pixel EGA
                and monochrome modes of the Paradise card, as
                this causes the super VGA monitor on a Dell to
                click a (loud) internal relay every time it
                changes modes. If you don't mind the relay, or
                you want the 800 by 600 modes, use PARAPLUS.DRV,
                above.

                Note: rumour has it that some Dell systems have
                been shipped with Headland Video 7 cards rather
                than Paradise cards. If your Dell system is so
                equipped... or if you can't get GWS to work in
                the super VGA modes with one of the above two
                drivers... try VIDEO7.DRV.

ATIWONDR.DRV    This is a driver for the ATI VGA Wonder and ATI
                VGA Edge cards. It drives the 256 colour screen
                in the 400 line mode, and will work with cards
                having 256K on them. The upper 256K on half meg
                cards will be ignored by this driver.

ATI512.DRV    This is a driver for ATI Wonder cards having 512K
                of memory on board. It will display pictures in
                up to 800 by 600 pixel resolution, selecting
                among the three available 256 colour display
                modes based on the dimensions of the image to be
                viewed.

GRAFDRV.DRV    This is a stock VGA card driver. You might want
                to use this if there is no super VGA card driver
                available for your card, however, as it handles
                the 16-colour and monochrome modes in potentially
                more useful ways than the internal VGA driver of
                Graphic Workshop does.

VGA400.DRV    This is a "gadget" driver for a stock VGA card
                which reprograms the beast into an undocumented
                320 by 400 line mode. It should work on any VGA
                card, but being undocumented one cannot be sure.
                In any case, while interesting, this mode has
                such a squashed aspect ratio that it's not really
                useful for anything. In addition, having heavily
                interlaced memory, it's painfully slow to update.

VGA480.DRV    This is another undocumented mode. It gets still
                more on the screen, with still more distortion.

To use one of these drivers, use GWSINSTL to select EXTERNAL for
display type and enter the path to your driver in the path name
field at the bottom of GWSINSTL screen. This should be the
complete path, including the drive letter. Graphic Workshop does
not assume that driver file names end in .DRV... you can call 'em
anything you like.
    The name of the driver you've loaded should appear in the
F10 "About" window when you're running GWS.EXE.


Writing your own driver

Also included with this version of Graphic Workshop is
GRAFDRV.ASM, the source code for GRAFDRV.DRV. This file can be
used as the boilerplate for writing your own super VGA card
driver. You will need a pretty good grasp of assembly language
and the hardware specific details of the card you want to write a
driver for to get this together. This file should be assembled
with Microsoft's MASM assembler, version 4.0 or better.
    The following batch file is useful in assembling
GRAFDRV.ASM into GRAFDRV.DRV... or any other driver you happen to
write.

MASM %1 %1 NUL NUL
IF ERRORLEVEL 1 GOTO PROBLEM
LINK %1 @AUTOLINK
EXE2BIN %1 %1.DRV
DEL %1.EXE
DEL %1.OBJ
:PROBLEM

    The file AUTOLINK must be present... it contains four
carriage returns, that is, four blank lines.
    In future releases we hope to include a number of SVGA
drivers with Graphic Workshop. If you write one using the
GRAFDRV.ASM skeletal driver and care to send us the source, we'll
be pleased to include it with future releases, with suitable credit.
    Registered users of Graphic Workshop who want to write
their own drivers are welcome to the source code for all the
above drivers... you might find some of the techniques used in
them helpful in writing your driver. The only conditions are that
you must be a registered user and we'd like to have the source
code for the driver you write when you get it working... we'll
include the object file in with future releases of Graphic
Workshop.
    We'll be happy to give you whatever help we can in
writing your driver, too.
    If you want the driver source files, please phone or
write us and we'll send 'em off to you.


Custom drivers

We've been asked on a few occasions whether we'll write custom
drivers for Graphic Workshop on behalf of various interested
parties. We might be able to, depending on time and whathaveyou.
If you really want a specific SVGA driver for Graphic Workshop...
for example, if you want to licence it for inclusion with a
particular card or computer... and you can't get it together
yourself, contact us. Our address is in GRAFWORK.DOC.