exxos's Atari, Amiga & retro forum

agranlund wrote: 06 Dec 2025 16:59 That looks hardware-blit related, as in an issue with the the fill-pattern data which is uploaded to the cards vram and used during hardware blit.
In this case the pattern is supposed to be a solid pattern to achieve a solid blitter-fill.
(the driver doesn't do hardware blits in 16 color mode so that further cements the idea that it's related to the blitting code)

agranlund wrote: 06 Dec 2025 16:59 Are all fill-styles broken?

agranlund wrote: 06 Dec 2025 16:59 No need to mess with the vmg tool for these drivers. The bibs are only there beacuse that's the only way Nova-aware programs can enumerate display modes.. They never exposed that functionality in the public Nova API so all individual programs opens and parses these files themselves, to get the information they need to pass onto the Nova API when they want to change display mode :/

In the case of the Cirrus, WDC and StandardVGA driver; the bibs are more or less dummies for that purpose, with a bit of name and resolution infos.
Timing or hardware specific register values are completely ignored since the driver doesn't need them -- the bios on the card knows how the card works and has the correct settings.

(For the old and official ET4000 and Mach drivers, those bibs are very hardware+driver specific and you may need to mess with them using the version of VMG.PRG which was specifically built for the driver you are using)

Atarian Computing wrote: 07 Dec 2025 07:21 Would this be a hardware or software problem if true?

Maybe I'm dumb but how on earth do I create a 1280x720 resolution for the card? If the BIBs have the resolution infos, I tried creating a 1280x720 but it doesn't appear anywhere to select.

agranlund wrote: 07 Dec 2025 13:38

Atarian Computing wrote: 07 Dec 2025 07:21 Would this be a hardware or software problem if true?

My gut reaction says software related.
Perhaps the next step would be to build you a version of the driver that has hardware-blit disabled, to narrow down and make certain it's related to that. Or perhaps just with blitter-fill disabled and leaving blitter-copy enabled.

Maybe I'm dumb but how on earth do I create a 1280x720 resolution for the card? If the BIBs have the resolution infos, I tried creating a 1280x720 but it doesn't appear anywhere to select.

You basically don't, at least not at the moment.
The driver can only set (S)VGA modecodes that the cards vgabios has support for.
(it doesn't actually set it itself so I can't take much credit, it just asks the bios on your gfxcard to do it)

And since all these cards are old none of them have modecodes for 16:9 resolutions.

I would like 1280x720 on these as well so it's on my wishlist to implement support for custom resolutions.
But it's a whole different ballgame compared to the almost one-liner of just asking the card to set one of its "built-in" resolutions.


The bib's only reason for existing, in this context, is to provide a list of names, sizes and such for whatever program wants to "know" what resolutions are available. So I populated a few "dummy" entries with the usual resolutions.

Now, that doesn't mean they necessarily exist -- it's an unfortunate side effect of the original Nova API lacking a "Give me all supported resolutions" functionality.
Thus, every program needs to open the bib, parse it, and then pass the bib-resolution info to the driver.

The driver will then disregard most of that info except for width, height, and bpp. Cross reference against what the particular card actually supports and finds the modecode for the closests match. Then asks vgabios to apply that modecode.

agranlund wrote: 08 Dec 2025 22:13 @Atarian Computing , check if this makes your card behave.
Should have hardware blitting disabled for Cirrus cards so it's only really meant as a way to verify if your issue is related to that or not.

emulator.prg.zip

( replaces emulator.prg in the folder c:\nova\default\auto\ )

Atarian Computing wrote: 09 Dec 2025 07:03 Thanks, but that doesn't work at all. I get a version error:

agranlund wrote: 09 Dec 2025 08:55

Atarian Computing wrote: 09 Dec 2025 07:03 Thanks, but that doesn't work at all. I get a version error:

Just to double check, emulator.prg was placed in c:\nova\default\auto and not c:\auto like so:


This one should be no different, but I zipped up the entire "c:\nova\default" maintaining folder structure:
C_nova.zip


(this time I actually tested on my computer. Swapped in the GD5434 card and ran with the blitter-disabled version of emulator.prg and could notice everything being very slow :) )