I don't think there is anything particular to the Headland chipset here - one of these boards was my main PC for years, and I played the hell out of Wolfenstein shareware. I had a SB 2.0 at the time, if I recall.

I also recently (2020ish) acquired another HT12/a system, replaced the surface mount 286 with h a socket and overclocked it... still no problems with Wolfenstein digital audio, that was with a SB 16.

Babasha wrote on 2023-09-27, 05:32:

What videocards are you all using? I get the strange freezes wit OAK videocards.

Ahead A5000B. Wolfenstein works perfectly with the digital effects off (runs indefinitely), so wouldn't suspect a video card issue.

After reading this thread and another that also encountered the issue with a 386sx-40 board, I'm struggling to find a common denominator. In that thread they tried multiple sound cards with the same issue.

I suspect it could be an I/O card issue. I do have LPT1 on IRQ 7 (nothing physically connected to LPT1). This has never caused me any issues on other systems, but maybe something odd is going on. I'm going to test removing the I/O card and also swapping the soundblaster over to IRQ 5.

ahyeadude wrote on 2023-09-27, 13:55:

I suspect it could be an I/O card issue. I do have LPT1 on IRQ 7 (nothing physically connected to LPT1). This has never caused me any issues on other systems, but maybe something odd is going on. I'm going to test removing the I/O card and also swapping the soundblaster over to IRQ 5.

Generally speaking, IRQ7 is fine. It's the original IRQ line for 8-Bit Sound Blasters, also.
Many games support it, thus.

That's because IRQ5 in XTs was being used for MFM hard disk controllers. Using it for Sound Blaster would have caused data loss.

And when Sound Blasters with 16-Bit ISA came out, they were made with ATs in mind (where IRQ5 was now unused by default).

The LPT port has an IRQ line, but rarely needs it. Merely OS/2 does access both LPT/IRQ at same time.

And that's pretty much it. Same IRQs can be used by multiple devices, just not at same time. Otherwise, things go amiss. But nothing will electrically break, normally.

Tried a lot more stuff that did not work...
- Switched to IRQ 5
- Physically removed I/O card
- Removed NIC
- Removed C/MS chips from SB
- Disabled gameport on SB
- Altered every possible memory setting in bios using amisetup
- Ran with no config.sys/autoexec.bat

Given that this is the only game I'm having an issue with, I'll chalk it up to some obscure DMA incompatibility. I'm out of ideas.

Okay, made some progress. I think the poster in the other thread was onto something by suggesting it might be an OPL2/3 compatibility issue.

I reviewed the Wolf3D sound code and it looks like AdLib and soundblaster code execution is intricately linked.

https://github.com/id-Software/wolf3d/blob/ma … WOLFSRC/ID_SD.C

This got me thinking... What if I tried to enable just digital effects, but no AdLib/OPL? And lo and behold, it works fine, no freezes.

So, I now think there is some sort of timing bug, or other issue that causes the game to hang while waiting for adlib or the SB to get to a ready state. But, it must be an extreme corner case since many others clearly can't reproduce it.

I'll keep digging, might try to compile the code in debug mode and see if I can figure out where execution is stalling out.

Okay, so I think I'm close to putting this to bed.

- I first tried swapping the SB 2.0 clone for an Orpheus I. This actually did work a little better, but I could not get past 2 hours of runtime without a freeze. It would pretty reliably freeze at the 2 hour mark.
- Then I tried swapping the VGA from the Ahead V5000B to a Diamond SpeedStar 64 (CL-5434). This did not improve the freezing issue.
- I then swapped to another sound card, an ATC-6631 (YMF719) and this actually works!

So it seems these motherboards have some sort of incompatibility with certain sound cards. The only addon card I was not able to fully remove to test for compatibility issues was my AHA-1542CF. I did try running Wolfenstein from a ramdisk, but that still resulted in a hang. So perhaps the incompatibility could be from the SCSI card (with certain sound cards, I'm positive there are no resource conflicts).

Either way, super picky machine for sound. Glad I found something that works.