Z386: An Open-Source 80386 Built Around Original Microcode
Z386: An Open-Source 80386 Built Around Original Microcode
hackaday.com
Z386: An Open-Source 80386 Built Around Original Microcode
There are many ways you can implement an Intel i386 CPU on an FPGA, with the use of original microcode probably being one of the most interesting approaches. This is what [nand2mario]’s z386 …

That is really impressive, I always feel nostalgic when specifications, original code, data books and schematics are lost over time.
Then some guys like said : not this time. Nand2mario’s GitHub z386 repository.