reenigne wrote on 2025-04-02, 13:40:

I'd think that running some thorough memory test software or booting from a known good DOS floppy (created on another machine) would be more likely to find the problem.

Thanks for the help! It was the dos version! The dos on the machine (and what I had previously SYSed onto a boot disk) is a period install. Ver gives:

1IBM Personal Computer DOS Version  3.30

I SYSed a disk with standard MS-DOS 5.0, and then 8088MPH ran just fine (well, my TV shows black and white for all the high color segments but that at least is a well known issue).

How strange - I thought we had tested it on old DOS versions! Not sure what it could be doing that's incompatible with 3.30. Glad you got it working, anyway.

There's an issue between Turbo Pascal, DOS 2.x, and some operations. It's in the runtime somewhere, so not easy to fix. Sorry you ran into this.

Area5150's loader is 100% assembler and doesn't have this problem. (I got better ;-)

I'm in awe watching these demos run - thanks for taking so much time and effort to make these old machines shine!

digger wrote on 2025-04-02, 16:05:

Are any of you in this thread familiar with the emulator MartyPC? It apparently runs 8088 MPH successfully. […]
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Are any of you in this thread familiar with the emulator MartyPC? It apparently runs 8088 MPH successfully.

So I guess it no longer "breaks all emulators". 😉

But it took emulator coders a long time to get it to run, so this demo remains an impressive feat regardless!

Link the the emulator running. 8088 MPH in a web player: https://dbalsom.github.io/martypc/web/player. … l?title=8088mph

I know reenigne's familiar with it. He helped me out a lot - it's primarily his work decoding the 8088 microcode that even made it possible.

To be fair it wasn't the first emulator to do so, 86box was handling 8088MPH quite well before MartyPC was even a twinkle in my eye.
The follow-up to this demo, Area 5150, is another story. If you haven't seen it, check it out. https://www.youtube.com/watch?v=fWDxdoRTZPc

I think Area 5150 easily takes the title of emulator-breaker from 8088MPH. It's taken me 3 years to run it reliably. If they ever come out with a third demo, I think I will retire.

reenigne wrote on 2025-04-02, 21:27:

How strange - I thought we had tested it on old DOS versions! Not sure what it could be doing that's incompatible with 3.30. Glad you got it working, anyway.

Not sure it's the DOS version. I've almost exclusively used 3.30 in MartyPC during development, and just in case it was PC-DOS vs MS-DOS I've tried both and can't reproduce....