3

I am attempting to make a ps1 emulator. I have looked through many websites for the opcodes for the r3000a processor which the play station uses. However, when I am running the opcodes from my ps1 bios, I get multiple opcodes prefixed with '011010' which is in none of the documentation. I can't find anywhere what this instruction is and it is the only one not recognized by my emulator.

Here are some sites I am using:
http://www.mrc.uidaho.edu/mrc/people/jff/digital/MIPSir.html
http://hitmen.c02.at/files/docs/psx/psx.pdf

Thanks for any help!

Ian Kemp
  • 28,293
  • 19
  • 112
  • 138
Vince
  • 613
  • 1
  • 7
  • 8
  • well i am not familiar with ps1/r3000a but if it is not documented (and it is not a secret instruction like Z80 has) then i think it could be some error in your CPU core emulation/simulation. if you do not process something correctly then the execution can jump to data area not code. Most likely a wrong flag somewhere. Try to trace step by step and check if instructions are executed properly. When not then repair them ... – Spektre Nov 29 '13 at 19:43
  • look here http://stackoverflow.com/a/19218993/2521214 for some ideas on debugging – Spektre Nov 29 '13 at 19:45

0 Answers0