PDA

View Full Version : VGA card compatible with low-res CGA mode?



m1k3e
March 11th, 2010, 08:17 AM
Hey all,

Just got a quick question. Does anybody know of any VGA video card that correctly supports the text-mode low res CGA mode? When I was growing up, I had a 286 clone with VGA graphics and I know for certain that it was able to play "Round 42" in all it's glory. That said, I also played a number of VGA games on it in full color. Any ideas? I have a 5150 and a 5160 with IBM CGA adaptors. I just picked up a 286 clone not too long ago, I'd love to find a VGA card that could do this so I could enjoy all my games on one machine. Thanks for the help! :)

per
March 11th, 2010, 03:35 PM
Mist possible. Most of the early VGA cards were some kind of hybrid between EGA and VGA, but it would not be illogical that some threw CGA and perhaps some other products into the mix.

I don't know of any spesific card that converts true CGA to a VGA monitor, but I guess it's one of the ones with both an analog 15-pin connector and a digital 9-pin connector.

The closest I have is the Trident TVGA 8800CS, but it has to be manually set to CGA-mode in advance by some switches on the rear end. In this mode, VGA features are not accessible and the host system also has to be set to CGA. Despire that, the RamDAC still does its work converting the digital video signals into analog signals (making an VGA monitor able to actually understand the video signals). Too bad most monitors can't sync ~15Hz, at least not without yelling at you (even if it's a LCD and at the same time does give a stable picture at that frequency)!

Fallo
March 11th, 2010, 04:01 PM
Just got a quick question. Does anybody know of any VGA video card that correctly supports the text-mode low res CGA mode? When I was growing up, I had a 286 clone with VGA graphics and I know for certain that it was able to play "Round 42" in all it's glory.

Round 42 is one of those games that uses the 160x100 pseudographics mode. The only thing you have to do to get this working correctly on VGA is adjust the Vertical Displayed register. I've done it with Moonbugs and The Exterminator before.

Marrr
March 12th, 2010, 03:55 PM
Most early VGA clones have register-level CGA compatibility option, you just need to enable it first with a chipset-dependent utility.
I just tried that Round 42 on a WD OEM8 card, based on PARADISE PVGA1A chipset - worked fine, the necessary utility is named VGA.EXE

vwestlife
March 12th, 2010, 05:50 PM
Aftermarket VGA and Super VGA cards start with official IBM VGA compatibility and then add various enhancements. Ironically, adding enhanced CGA compatibility as an enhancement would render the card not fully VGA compatible, since IBM included neither the 160x100 16-color "graphics" mode nor the white/red/cyan color palettes as part of the official VGA standard. So, you will not see this full CGA compatibility in hardware on a VGA card, but in some cases software drivers are available for specific cards and manufacturers, as others have mentioned.

per
March 13th, 2010, 06:08 AM
you will not see this full CGA compatibility in hardware on a VGA card,
If the compabilitiy is present, it's in fact present in hardware. The thing is that its not activated by default, so all the software does is actually just to activate it.

I think maybe the ATI VGA-Wonder will be able to do CGA. If you get the card, I could send you the software.

m1k3e
March 28th, 2010, 07:18 AM
Ah, thank you for all the responses! Right now I have an IBM CGA adapter in the computer, but I'm going to take it out and drop in a Paradise VGA board that I have laying around. I *think* it's based on the PVGA1A chipset, I have to double check when I get home. Anyone know of a place to find that VGA.EXE utility? I've been searching for a little and can't seem to come across it. Again, thanks for all the responses!

Raven
March 28th, 2010, 11:57 AM
Mist possible. Most of the early VGA cards were some kind of hybrid between EGA and VGA, but it would not be illogical that some threw CGA and perhaps some other products into the mix.

I don't know of any spesific card that converts true CGA to a VGA monitor, but I guess it's one of the ones with both an analog 15-pin connector and a digital 9-pin connector.

The closest I have is the Trident TVGA 8800CS, but it has to be manually set to CGA-mode in advance by some switches on the rear end. In this mode, VGA features are not accessible and the host system also has to be set to CGA. Despire that, the RamDAC still does its work converting the digital video signals into analog signals (making an VGA monitor able to actually understand the video signals). Too bad most monitors can't sync ~15Hz, at least not without yelling at you (even if it's a LCD and at the same time does give a stable picture at that frequency)!

Do you have any information on the Trident 8800CS - I happen to have just recently deciphered my favorite ISA card to be that exact card, with lots of research on the chips and numbers on it (took months off and on - sparse info!). The pages I have found seem to have inaccurate information on what switch and jumper positions do what, but I was able to get it into EGA and VGA modes, and a half-broken MONO mode - I'd like to get it outputting anything I want properly though, if you know how (specifically mono).

Marrr
March 28th, 2010, 12:30 PM
Ah, thank you for all the responses! Right now I have an IBM CGA adapter in the computer, but I'm going to take it out and drop in a Paradise VGA board that I have laying around. I *think* it's based on the PVGA1A chipset, I have to double check when I get home. Anyone know of a place to find that VGA.EXE utility? I've been searching for a little and can't seem to come across it. Again, thanks for all the responses!
This seems to be the same: http://bbs.actapricot.org/files/area34/vgaplus.exe

per
March 28th, 2010, 08:31 PM
Do you have any information on the Trident 8800CS - I happen to have just recently deciphered my favorite ISA card to be that exact card, with lots of research on the chips and numbers on it (took months off and on - sparse info!). The pages I have found seem to have inaccurate information on what switch and jumper positions do what, but I was able to get it into EGA and VGA modes, and a half-broken MONO mode - I'd like to get it outputting anything I want properly though, if you know how (specifically mono).
I also encoured the same problems as you when trying to find the settings, but at this time, therse settings are the best match so far:
http://th99.dyndns.org/v/U-Z/50084.htm