Hello. Please help me about PS1 and PS2

[luc-ita]

I've a new question regarding the PS2 system, and the PSP system.

In the PCSX2 emulator and PPSSPP emulator there's a way to use the log function to trace instructions, like with MESS?

Or another emulators or any other way to do this?

[Abystus]

Not to my knowledge. There are options in PPSSPP that make it appear that you can, but the functionality doesn't seem to work. I approached some of its developers in their IRC chat about it a while back, but it seemed as though they didn't want to implement the feature (logging to a file). There may be some way to log to a window (command prompt), though at this time I am unsure as it has been quite a while since I last used those emulators.

[luc-ita]

Many thanks again, Abystus!
I'm asking because I'm trying to do any "anywhere" codes but...without a log or a way to trace...I think it's impossible, for me.

With Cheat Engine it's possible to make log files?

[Abystus]

Many thanks again, Abystus!
I'm asking because I'm trying to do any "anywhere" codes but...without a log or a way to trace...I think it's impossible, for me.

With Cheat Engine it's possible to make log files?

Yes, Cheat Engine has a "Break and Trace" option that can create a log file of executed instructions. Keep in mind that it will not log anything before the breakpoint, so you may still have to do some manual backtracing. Branch Finder supports the log files generated by Cheat Engine, so this may be helpful to you as well. As far as creating "Hit Anywhere" type codes without trace logs, it is possible with some manual backtracking, though it is usually a much slower process overall.

[luc-ita]

Very interesting informations!
On creating "anywhere" codes...I'm a newbie and I don't know how to backtracking without a log. I've tried several times but I don't know a right way to do this. And always I ended with a failure.
Do you know how I could understand better a proper way to going back in the code without any log file?

Thanks for helping me a lot!

I'm sorry for all these questions

[Abystus]

Debuggers where you can see the stack will show you the return address listed on top of the stack after a call is made. Using this information you can determine where the current routine was called from. You can also set breakpoints on the "RET" instructions, and use a single step into to return back to the calling routine. Cheat Engine along with some other emulators include an "Execute until return" option that allows you to simplify the previous method, but sometimes it doesn't work properly due to other returns happening before the one you want.

Visual Example:

[B][COLOR="#008000"]Routine0[/COLOR][/B]:
{
   [B]Call [/B][B][COLOR="#008080"]Routine1[/COLOR][/B]
     [B][COLOR="#008080"]Routine1[/COLOR][/B]:
     {
        [B]Call [/B][B][COLOR="#0000CD"]Routine2[/COLOR][/B]
           [B][COLOR="#0000CD"]Routine2[/COLOR][/B]:
           {
              [B]Call [/B][B][COLOR="#800080"]Routine3[/COLOR][/B]
                 [B][COLOR="#800080"]Routine3[/COLOR][/B]:
                 {
                     < -- [B][COLOR="#FF0000"]You are here[/COLOR][/B]
                 }
                 [B][COLOR="#800080"]ret[/COLOR][/B] < -- breakpoint here and step to find call location
           }
           [B][COLOR="#0000CD"]ret[/COLOR][/B] < -- breakpoint here and step to find call location
      }
      [B][COLOR="#008080"]ret[/COLOR][/B] < -- breakpoint here and step to find call location
}
[B][COLOR="#008000"]ret[/COLOR][/B] < -- breakpoint here and step to find call location

[luc-ita]

The more I ask the more I learn! A huge thanks to you Abystus! And to all the users who helped me a lot!

I'll try your method with any game made with the Unreal Engine 3. Because when I find a value...I can't do anything because all values are in a memcpy function! And I realy don't know how to find the "source" of a value, outside of the memcpy function...

With your method I hope to have success!

[luc-ita]

Once again I need help! On PlayStation system! How I could find base pointers? I can't find a way and really need help! Harry62 and Pyriel, maybe you could advice me.
Maybe I could use CheatEngine to find what address holds a register. Address that changes on every level\area\situation.
But I'll wait if someone could answer me.

[Helder]

Use no$psx or better yet use MESS as it has tracing logging to file and has helped me immensely in making hard codes for the PSX.

[luc-ita]

I've succeffully found the BasePointer for the Aku Aku mask in Crash Bandicoot 2. Thanks to your advice!