Originally Posted by jimbob
Well I'm probably even more out my depth than you, but I always thought that microcode was completely internal to the cpu, externally you still have to use the "exposed" instruction set.
From your quote, it sounds like this might not be the case, but you would have to convince AMD or Intel to create 68k emulation microcode for you, interesting idea, I wish I knew more about this stuff but it is generally over my head.
Thanks for your reply jimbob. I'm glad you think the idea is interesting, even if neither of us know whether it's possible to implement.
With regards to convincing AMD or Intel to create 68k emulation microcode for you, certainly the secretive nature of microcode is a barrier here, but perhaps it would be possible to reverse engineer the microcode design to be able to implement a sort of 'microcode compiler', i.e. take a fixed design like the 68060 ISA and use a tool to translate it to the microcode of the CPU you're using. To start accumulating the knowledge needed to do this, could disassemble the microcode patches that Intel and AMD provide in binary form, to get clues about how to write microcode, and go from there.
I'm not saying it'll be an easy thing to do, and I don't even know if it would be possible, but it would be good to know if such a possibility existed.
More information definitely welcome!