@Eep386, did you keep a copy of the unmodified MV035F BIOS, and could you please post it? Thanks, Robert

Thanks for checking, @Predator99, I'll give that dump another go. Sorry for not answering your PM, the board won't let me use that function until I reach a certain number of public posts. Robert

Thanks for the memory refreshers and explanations, folks!

Good idea re. the Landmark/Supersoft ROM and Checkit. I also remembered the Diagnostics disks for IBM. Later 80286s will have memory expansion features, but I need to look up what in terms of XMS/EMS et al. is possible ... and how to test it. It's been quite a while since that was relevant 😀 Robert …

@Predator99 I'm working my way through the BIOSs integrating them in MAME ... done most of the 286's and am halfway through the 386s. Can I bother you again with checking one of your dumps ... #21 of the 386s ... other BIOS versions from boards with the same chipset run in the emulation, e.g. #4, …

Hi folks, which features would you test / what programs would you throw at an emulator to make sure it's working as best as possible? I'm not after graphics tests, just the motherboard emulation. Robert

Hi and thanks again! Unfortunately I couldn't get the ROM from the Laptop board, #15, to run. #16 is fine, the Olivetti one (#17) starts up but complains about "Timer Sync Error", so probably something is not yet emulated properly. #18 ( ZM-720-02) has the IBM AT ROMs dated 01/10/84, if you …

Good call! The Morse ROM now runs, but the Uniron is still complaining ... it'll be interesting to see if you can get it to run in PCEM.

Hi, thanks for checking. I'm slowly plodding on. #9, U3911-V3 Uniron, is announcing to the world that its ROM is bad by beeping 1-1-4. #13 is the same as the Siemens PCD-2 (not L or M) that's already in MAME. Our dumps are identical (so I presume correct), but the emulated machine complains about a …

Hi Stiletto, thanks for clarifying this! I'm going slowly through the list of ROMs you posted and add the load information (name, checksums and hardware info) to MAME. I can help you set up MAME once my commit is in. The process is that contributors offer their work in form of a pull request for …

No wasted time at all! By adding the ROMs to MAME we find these errors, your archive is meant for people to experinent and repair their boards, this aligns very well with MAME's purpose. I'll post here if any others give me grief. It's not in mainline MAME yet as I have to push it to GIT and hope …

The access methods BIOS dump is strange, the standard value at location F0000 is 0f000h:0e05bh instrucion (far jmp). The first screenshot is from the MAME debugger window showing the SUNTAC BIOS from befor as a comparison. standard.jpg The access methods BIOS looks like this instead at the relevant …

It's working in MAME, I just booted an image of DR-DOS 3.41 The "refresh timing error" persists after setting the information in the BIOS, so it's aware it's not running on the real thing. Filename 0001.png File size 7.39 KiB Views 6189 views

Thanks for checking! BIOS #s 2-4 are working after trimming them down to 32K, #2 was already in. If you can, please dump it via DEBUG - usually seeing a botched jump vector means I'm loading the ROMs incorrectly, (e.g. odd instead of even and vice versa). If all else fails I'll pass that one to the …

#37 Manufacturer/Identifier: Precise 860407 Chipset: BIOS/Version: Pyramid V2.14 Filename P1210010.JPG File size 1.46 MiB Views 3553 views

Thanks for the explanation! Do you have 80286 board #1 (the AMI before they became American Megatrends) in a working condition? I ask because the ROMs somehow don't line up for the usual jump vector at at the end of the ROM and it ends up going into the weeds - yet it looks like a bog standard early …

@Predator99 may I ask you how you dump the BIOS ROMs? (Eprom reader vs. NSSI vs. DEBUG). I started adding the 80286 ROMs to the MAME emulator, and at least #2 and #3 in your 80286 thread have the EPROM type visible in the photo (27256 = 32KB) but your dumps are 64KB and duplicate the content. Heads …