Collection of scripts used for hacking P6 (Pentium Pro,II,III) microcode.
https://github.com/peterbjornx/patchtools_pub is a tool for creating and unpacking microcode patch files. It is probably the easiest way to get some microcode to disassemble and tinker with - You should be able to figure out how to dump the whole ROM that way.
I documented much of my research that lead to this tool in tweets which I've collected on my website:
https://pbx.sh/pentiumii-part1/ https://pbx.sh/pentiumii-part2/
Only public resources and publically available hardware were used by the author to produce this program.
The code in these scripts was written as part of ongoing research and as such is not very tidy, it is provided for study only and should not be relied on in any way
These scripts are used to convert between "physical" MSROM/RAM layout of microcode and logical micro-op layout.
Micro-ops occur in triplets and as such every fourth address in the descrambled form is unused.
The scrambled form represents the layout as it is found in patch files and in the on-chip mask-ROM.
These scripts are a simple disassembler and assembler for P6 microcode.