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Frankly spoken, I'm out of my depth now. I think you need to gather more data on the failure of your Quadra board. Can you do some electrical analysis of your board and compare the signals it generates with a known working board? That would be very helpful. Otherwise, we won't be able to go a...

Thank you for pointing me to FDisasm that I'm aware of. I personally never considered to give it a try because I don't use Mini vMac emulator I never seen any ROM formatting files for the ROMs of my interest (PowerMacintosh 6100 and newer) MAME/MESS offered me anything I need in just one...

This would be possible if your board had EEPROM or Flash storage. It's a well-known fact that all Apple desktops in the 90s use 3.6V lithium batteries to maintain non-volatile memory. That means that PRAM (NVRAM) is actually a small amount of CMOS RAM powered either by the mains or the battery...

What's about the 68kmla Wiki?

If you're going to gather some knowledge about a specific ROM or ROMs, the question is if the static analysis (i.e. disassembly/hex dump) would be the right tool for the job. You can surely run a disassembler over your ROM dumps. The problem is that the most disassemblers are just dumb tools...

Yes, I agree. Mouse movements involve interrupt signals. That's indeed smth you want to check next...

I don't think it's possible. It's true that the ADB as a single-line bus requires precise time slices. But this leads to the following logical conclusion: if this timing is somehow broken, the whole ADB communication will become broken. Any partial failure can only happen after the ADB...

Any chance to take a look at such a font?

These markings are often confusing and mostly meaningless. If I had to guess, it looks like a Motorola-fabricated clock driver IC (MC74F803), similar to those used in Amiga, see this Wiki page. It seems to provide clocks for the CPU. You'll find the datasheet MC74F803 for on the above mentioned...

Please tell us the part number or post a picture...

Is there any place around here where I can dump all CUDA-related stuff (including pictures, schematics, firmware disassembly etc) I gathered so far? A kind of editable Wiki?

368 is the correct amount of required RAM. 386 was a typo. Sorry.

Sure. I attached three different binary dumps. Disassembly including my personal comments aren't included there. I need to take some precautions and don't post those here because they're surely copyrighted...

CUDA Firmware actually uses 386 bytes of RAM. It's divided into two main partitions as follows: $0090 - $00FF various local variables $0100 - $01FF 256 bytes of PRAM --> yes, PRAM is simply a part of the CUDA's internal RAM; since it's always powered (either by the mains or the battery)...

Well, damaged ADB circuitry is very unlikely then. This is good news indeed. Bad news: it looks like you're experiencing another hardware-related issue. Is it possible to boot up the machine with PRAM battery removed?

Last question: what happens with a keyboard attached? Does it respond when you press the TAB key/ any other key?

Hmm, if the Keyboard works as expected (different keys recognized) then it's safe to assume that the ADB circuitry is intact. I'd look for software-related issues. Does the mouse pointer respond to mouse movements during boot or is it frozen?

With a PIC/AVR, is it possible to assign a custom functionality to arbitrary pins?

Some more to check: is the failing mice attached directly to computer's ADB port? did you try to attach the Keyboard instead? Does it work then? tried with only one device at a time? I know these are very basic steps I assume you already tried out. Please double-check them anyway...

Could you shoot a picture showing the whole ADB circuitry (the connector and the 342S0440-B ASIC)?