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I was following along OpenTechLab [0] as they tried to reverse engineer a real CPU used in HDMI repeaters. The instruction set was already partially reversed [1
by zxcvgm 7y ago
I was following along OpenTechLab [0] as they tried to reverse engineer a real CPU used in HDMI repeaters. The instruction set was already partially reversed [1], but gaining code execution allowed a small stub to be written to infer more based on before & after register states.
[0] https://opentechlab.org.uk/ https://opentechlab.org.uk/
[1] https://github.com/v3l0c1r4pt0r/lkv-wiki/wiki/Instruction-Set-Architecture https://github.com/v3l0c1r4pt0r/lkv-wiki/wiki/Instruction-Se...
- v3l0c1r4pt0r 7y agoFinally mentioned CPU turned out to be a core with OpenRISC architecture, but nevertheless it was quite interesting challenge. I did my part, based completely on source file, I was sure was compiled into binary (part of FreeRTOS), but, yes, possibility to execute code and observe the results allowed guy from opentechlab to achieve a lot more than I did.