Atari-Forum

The problem is that people spread a lot of BS, declaring it as facts. And it is alarming that those are mostly people that claim to understand the meaning of universe and everything, but they are wrong. This is true on so many levels and seems to proof that humanity is destined to fail very badly. ...

I have also experienced this attitude before and expressed my disgust about it. If someone invested into some part of ATARI history, they took a personal risk and invested time and/or money. They might have reasons that other people don't like or share, but who decides that it has to become public d...

-> Idek Tramielski - unfortunately it is schematic of bigger version of PCspeed with coprocessor. No JEDs for three GAL chips. AFAIR it works with the same GALs. It is just an enhanced version with optional FPU. In fact, I built this version back in the days without the FPU part. Unfortunately, I c...

And for the low res on M32, I checked the extended registers and all the information I could find in libvga.config and svgalib but you're the specialist here -_- I wish I were....whenever I add another DAC to the code, it is more like pulling teeth. Some other news about the audio clicks, I'm worki...

I don't know if I will be able to release the demo for 320x240, last time I tried to create this mode with VMG.PRG (Mach32), it wouldn't allow me to create low resolutions. The reason for this is the different way the ET4000 and the Mach32 work. The "Low res." button in VMG actually sets ...

BTW which RAMDAC does your Mach32 have? It seems the colors are wrong with Bt481. Mine also has the ATI68875. The BT481 is not very common and afair limits the Mach32's abilities. I made a special version for Frank some time ago that supports the BT481 partially. But I guess its only a TT version. ...

Same observation with the Mach32:
Blitter version shows clicking noises.
Software version shows noises at 8MHz and 16MHz-cacheoff. 16MHz-cacheon is pretty (but not totally) quiet. It clicks maybe 5-6 times during one loop.

I first removed the 68882, replaced it with a 68881 and then swapped out the VME GALs. In the end it was the Blitter. My board originally has a C101643 (9033ERB) Blitter. After replacing with a MM9092V (S9006) Blitter, the demo works. Now, I am still curious about the clicking noise. In my current ...

I first removed the 68882, replaced it with a 68881 and then swapped out the VME GALs. In the end it was the Blitter.
My board originally has a C101643 (9033ERB) Blitter. After replacing with a MM9092V (S9006) Blitter, the demo works.

I swapped my C301712 with a C300588 in my CA400677 board. Clicking noises are still there, maybe a little less, but still present. Full demo still crashes. Do you run it with 16Mhz+cache? How does it crash? yes, 16MHz +cache, but I also tried other startup conditions. Here are two examples with 16M...

I swapped my C301712 with a C300588 in my CA400677 board. Clicking noises are still there, maybe a little less, but still present.
Full demo still crashes.

double post

My "old" board, also has the C301712, but works. But didn't you say that you "old" board also had the noise/crackling issue? So by "works" you mean that it doesn't crash? That still would not rule out that the audio issues are related to the sound shifter model. I don'...

My "old" board, also has the C301712, but works. Now it gets really confusing.

Okay....more testing with my very old MegaSTE (CA400677 serial# M000750) - this board does not work with the MonSTer when 16MHz is selected and demonstrates other unusual behavior BUT...the full demo works on the old board (with external C101643 Blitter). It crashes on the new board ( with COMBO boa...

No idea if this is relevant, but my MegaSTE has the National Semiconductor version of the sound shifter (C300588), which - I think - is fairly unusual for a MegaSTE. At least, the motherboard pictures I find online all show the newer IMP version (C301712). My main MegaSTE has the C301712 version an...

@fenarinarsa: Could you please post your full AUTO folder setup?
The full demo crashes for me currently shortly after start....
...with OGFA, but also with the SUPER_SE(Z) GAL....

I tested with my MegaSTE and can confirm clicking noises on my headphones when I use the blitter version.
(OGFA GAL and mods)

BUT, I also get the same noises when I use the software version and set the MegaSTE to 8MHz

Another find....untested.

Found something. Maybe somebody can make use of it....

I can't say much about the AB drivers. This was all too long ago for me since I owned the AB.
I (try to) disable the caches whenever I access the registers of the card(s) and re-enable them right after that.

This is not quite how it works. The frequencies you are referring to are the bandwidth for drawing the screen. Since each pixel in 65k needs two bytes, the bandwith of the DAC needs to be much higher.
Check page 8: https://datasheetspdf.com/pdf-file/5305 ... TT20C490/1

ok, that card supports 1024 x 768 px in 65K Colors (Interlaced or Non-interlaced) and have the acceleration which both sounds cool, unfortunately that mode needs 1.5MB RAM and max resolution is: 1280 x 1024 px / 60 Hz Non-interlaced Maximum Resolution 1024 x 768 px / 85 Hz Non-interlaced Maximum Re...

Cyprian wrote: ↑Mon Dec 06, 2021 2:52 pm will this modification work with 2MB ET4000/W32i ?
https://www.atari-forum.com/viewtopic.php?f=27&t=41291

No.

This card has a 80MHz DAC that limits what the card can do. The W32i was mainly created to take advantage of cheaper DRAMs when accessed interleaved. Currently I only support 1MB W32i cards (without using DRAM interleave), mostly to be able to use the acceleration of the W32i chip (which is actually...