z386: An Open-Source 80386 Built Around Original Microcode

 (nand2mario.github.io)

30 points | by wicket 1 hour ago

2 comments

  • cbdevidal 7 minutes ago
    Of course they tested Doom :-D

    They might also run Linux kernel 3.7, that supported i386. Gray386linux is still maintained, and runs a patched 3.7 kernel.

    https://github.com/marmolak/gray386linux

  • mmastrac 51 minutes ago
    Did the microcode disassembly find any useful backdoors to read microcode without decapping?
    [-]
    • nand2mario 45 minutes ago
      Not really. The 386 does not have an interface to read the ROM direclty. Instead, it uses the Built-In Self-Test (BIST) to verify the ROM's contents. It's basically a checksum-like mechanism that verify the integrity of the CROM.