A PCWindow replacement for CBM Bridgeboards for Amiga computers.
In short, I like crazy projects which don't make any sense whatsoever.
Now that we got that out of the way, here are a few more reasons
a bit longer:
The old PCWindow software was designed for 1988-state Amiga computers.
it doesn't play nice with fast CPUs and it doesn't support RTG systems
properly. It was designed to also run with older Kickstarts and it best
works with those. This is where Viaduct comes in, which was designed
for "modern" Amiga, OS3.1, RTG and fast CPU expansion. If you have a
fast, expanded classic Amiga system, there's a good chance Viaduct
will work better for you than PCWindow ever did. Viaduct can also
display the PC's Color output in a Workbench window, while PCWindow
only supports this for Mono output only.
Please note that this is an early version of Viaduct and doesn't support
all features of PCWindow currently. Also, not all hardware combinations
supported by janus.library and the CBM driver stack was tested.
I wrote this software for my own needs, and to support things I found
interesting. It's entirely possible that it won't fit your use case, or
it doesn't support things you find important. In this case, please send
a feature request or a bug report. Please also read the "Known Issues"
* a fast 68k CPU, like a 68040, 68060 or faster
* an RTG card with Picasso96 or CyberGraphX drivers and at least
800x600 Workbench resolution in 256 colors
* 16 free pens on the Workbench screen
* a CBM Bridgeboard, like the A2286 or A2386sx
* AmigaOS 3.1 or newer
* properly installed and functioning janus.library and PC Tools
Copyright & Contact
Copyright (c) 2018 Karoly Balogh <charlieamigaspirit.hu>
THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN
AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
This software is written with best intentions, and in the hope that it
will be useful, but it is based on information obtained with reverse
engineering of computer systems and hardware otherwise unsupported and
end of life for decades. In other words, if this software sets your
Amiga or PC Board on fire, I'm not responsible. Use at your own risk.
- 40x25 Color Text Mode is not supported.
- Underline and blinking is not supported in the various text modes.
- The rendering engine supports a lot of options to improve usability,
speed and rendering quality, but currenty the default settings are
hardwired. There should be a settings GUI to change these options.
- The code was not tested on an AGA screen and will probably break. I
have no functioning AGA system with a PC card at this point, and no
Windows system to try with WinUAE.
- Running on an ECS screen is not supported at all (ECS doesn't have
enough colors in high res).
- Viaduct relies on a *FAST* hardware BltTemplate() implementation in
the video driver, and will probably be very slow if it's missing.
(Some RTG cards are known not to implement this.)
- The keyboard emulation is still not complete. Changing Num Lock state
is unsupported for example.
- Probably there is more. But I prefer to release early and often,
rather than try to polish it forever and never get it out there...
- Fix 40x25 Color Text mode support
- Fix other aspects of CGA and MDA emulation as far as the bridge
hardware and performance allows.
- Resizeable/scrollable main window
- Full screen mode
- Settings GUI (possibly with MUI 3.8)
- Clipboard support
- GUI localization
- Performance improvements and bugfixes
Q: But... Why?
A: See above.
Q: Did you really develop this in Free Pascal?
Q: You seem to have a lot of free time.
A: I don't have a lot of free time, and that wasn't a question.
Q: What hardware did you use to develop Viaduct?
A: I used my Amiga 2000, with a Blizzard 2060, PicassoIV and an A2386sx
or A2286, running AmigaOS 3.1 (original Commodore version). I also
used a MacBook with OS X to crosscompile with Free Pascal.
Q: Will you open the source code later?
A: This is possible, yes. The source is already on GitHub, in a private
repository. But I want to keep it private until it reaches a
"functional and complete enough" state. If you want to contribute
before, please contact me in e-mail.
Q: I want to contribute somehow, but I cannot code. Is there a way I
A: Send bugreports and test hardware combinations. Also, I'm looking
for a nice 4 color and MagicWB icon for this project, for the main
file itself, and the folder itself.
Q: Could you support other PC Bridgeboards like the Vortex GoldenGate
A: Theroetically yes. This depends on the availability of programming
material for these cards or the effort it's needed to reverse
engineer it. I have a GoldenGate 386sx, but I made no effort in
researching it yet.
Q: CGA or MDA sucks, so I'm using a VGA card in my Bridgeboard setup.
Can Viaduct display the VGA card's picture in a Workbench window?
A: No. Viaduct can only display the picture of the built-in emulated
MDA or CGA display adapter. The Bridge hardware doesn't support
promoting the picture of an external ISA card directly to the
Q: CGA colors suck. Couldn't Viaduct emulate EGA or VGA? Or at least
A: Adding emulation of hardware anything beyond the Bridge's hardware
emulation can support is probably too complex and would be far too
slow on the average RTG Amiga, therefore doesn't worth the effort,
Q: I see Viaduct trying to autodetect the Video mode, but it doesn't
work for my setup. How can I fix it?
A: In the PCPrefs application, make sure either MDA or CGA emulation,
or both are enabled, and the default video configuration is set
properly to an enabled emulation mode.
Q: I see Viaduct trying to autodetect the Video mode, but it doesn't
work for my setup. How to force Viaduct into a certain configuration?
A: Create an environment variable called "VIADUCT_VIDEO", which should
contain "CGA" or "MDA", without the quotations. For example the CLI
> setenv VIADUCT_VIDEO MDA
before starting Viaduct will force it into MDA emulation mode.
Copy ENV:VIADUCT_VIDEO to ENVARC: if you want to make this setting
Thanks & Additional Credits
Peter "Ratman" Foldesi
- for test hardware support extraordinaire
Zsolt "adsr" Mari
- for test hardware support
Marcus "Alb42" Sackrow
- for his awesome work on Free Pascal Amiga version and various
- Implemented initial 80x25 Mono Text Mode and MDA emulation support
- Automatic detection of the right emulation mode on start, based on
the Bridgeboard's configuration file.
- Added VIADUCT_VIDEO environment variable, to force a specific display
mode and ignore the config (See the FAQ above.)
- Implemented delta rendering for 320x200 4 color mode, speeds up
refresh where the application (usually games) only update small
parts of the screen.
- Fixed trashed display of the first frame when Viaduct was started
while the PC was in 320x200 4 color mode.
- Fixed silly a bug, where the cursor drawing could cause a deadlock
depending on the CRTC register contents
- First version.