VOGONS


First post, by LukeLovesRetro

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Hi, I have been trying to get a cirrus logic gd5424 to work for months now. It displays graphics fine but when i try to load a textmode program like qbasic or dos edit it displays garbage (see attached pic).

20170426_111324.jpg
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I have searched many forums for a solution to the problem to no avail. Please any help would be greatly appreciated. Thanks L.

Reply 1 of 10, by akula65

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Cirrus Logic had an assortment of drivers and utilities for various OSes for the GD542x chipset (and this is not necessarily a complete list):

542xvga.exe BIOS Overlay for ISA DOS
542xvgal.exe BIOS Overlay for VLB DOS
k542x-d1.zip Utilities DOS
k542x-d3.zip Driver OS/2
k54242e.zip Driver Win3.11
k54242e2.zip Driver Win3.11
k542xd4a.zip Driver WinNT3.1
k542xd4b.zip Driver WinNT3.1
k542x-d5.zip Driver WinNT3.5

You might need to use a driver or utility for whatever OS you are using. You may also need a copy of PKUNZIP to decompress one or more of the above packages.

Good luck.

Reply 2 of 10, by clueless1

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Have you examined the card carefully? Might there be a damaged component on the board that is only responsible for text mode display?

The more I learn, the more I realize how much I don't know.
OPL3 FM vs. Roland MT-32 vs. General MIDI DOS Game Comparison
Let's benchmark our systems with cache disabled
DOS PCI Graphics Card Benchmarks

Reply 3 of 10, by Jepael

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The card is so integrated there's no component that would only affect text mode, and there's a lot of unanswered questions. If it was an hardware error, it should affect graphics modes as well - except if font area of BIOS ROM does not work..

ISA or VLB card? Is there a "wait state" jumper? Does it work during BIOS POST screens before DOS loads (if so, does it work without memory managers?)
Is there a caching setting for video BIOS (that's the place the font is loaded to video ram when changed to text mode).

Reply 4 of 10, by clueless1

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Jepael wrote:

The card is so integrated there's no component that would only affect text mode,

I didn't get that it was an integrated graphics card from his post. I have a TNT2 M64 PCI that has issues in DOS text mode (ghosting/banding) but not in graphical games. There is a small component close to the PCI connector that has visible damage, so I attribute that component to the text mode issues. Hence, my suggestion.

The more I learn, the more I realize how much I don't know.
OPL3 FM vs. Roland MT-32 vs. General MIDI DOS Game Comparison
Let's benchmark our systems with cache disabled
DOS PCI Graphics Card Benchmarks

Reply 5 of 10, by LukeLovesRetro

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The card itself is an ISA variant of the 5424. I have examined the card fairly thoroughly and seems to be in good physical condition. On boot all seems ok, displays post fine and in bios ok. I havn't tried the cirrus bios overlay though and shall give it a shot, will report back with results. Thanks for the info.

Reply 6 of 10, by derSammler

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There is a small component close to the PCI connector that has visible damage, so I attribute that component to the text mode issues.

There is no such thing as "components for text mode", apart from the char rom of very early mda/cga cards.

Judging from the screenshot, it's pretty much the VGA BIOS ROM that is corrupted.

Reply 7 of 10, by clueless1

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derSammler wrote:

There is a small component close to the PCI connector that has visible damage, so I attribute that component to the text mode issues.

There is no such thing as "components for text mode", apart from the char rom of very early mda/cga cards.

Then I'm probably wrong. Here is what I'm talking about. See the missing capacitor at C96:

tnt2m64.jpg
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This particular card has banding and ghosting issues in text modes (BIOS and MS-DOS). But when I play graphical games, the issues go away.

The more I learn, the more I realize how much I don't know.
OPL3 FM vs. Roland MT-32 vs. General MIDI DOS Game Comparison
Let's benchmark our systems with cache disabled
DOS PCI Graphics Card Benchmarks

Reply 8 of 10, by Jepael

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derSammler wrote:

Judging from the screenshot, it's pretty much the VGA BIOS ROM that is corrupted.

Not if it boots correctly into DOS text mode in the first place.
If the VGA BIOS ROM contents is shadowed and that copy in RAM gets corrupted, possible, but it should corrupt the code in BIOS as well so it would crash pretty quickly when changing video modes.

Maybe caching, ROM shadowing configuration or memory manager configuration issue. I'd disable EMM386 or at least double check its parameters, maybe HIMEM as well. Then which memory areas are shadowed, and if there is a memory mapped peripheral like a network adapter that overlaps the video BIOS area. Also a good test is that If it works in another PC, then the video card should be fine.

Reply 9 of 10, by LukeLovesRetro

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Hi all just an update. I have tried several versions of the bios overlays and rechecked the card for physical damage. Have tried in another pc and disabled memory managers the issue still persists. Will continue to look for a solution as it is the only 1mb isa vga card i have. Maybe will look for another card though i would like to fix this issue.