BattleTanx (U) SP DMA errors about project64 HOT 6 CLOSED

Depending on whether or not project64 is able to associate this with any core CPU/interpreter faults within pj64 itself, I will most likely end up self-assigning this as a RSP interpreter bug with unimplemented SP DMA address range handling. I don't even have this implemented in my own RSP plugin actually....

from project64.

Honestly, I don't even press a button. I just disable frame limiter and the error happens early on in the intro. The error happens on 1964 1.1 as well.

from project64.

Interpreters shouldn't be giving random/unpredictable results like this though I would have thought?

yes, they should be consistent if all the input is the same, if you eeprom is different, or you start pressing keys timing and code paths will be different. Also if fixed audio timing is not on then that can also cause inconstancy.

from project64.

Okay in that case new steps to reproduce:

1. load ROM
2. just sit there without pressing START button until SP DMA :)

Seems to be consistent every time this time, with no key presses on my part, and I have just turned on Fixed Audio Timing anyway.

So I guess that means the ROM really is attempting to SP DMA an unmapped RCP memory address...it's a shame because if I "fix" this SP DMA error in pj64 RSP interpreter, there will be few error messages left to interrupt emulation in case the RSP ucode gets corrupted by the CPU recompiler or something (causing ear-damaging audio)...I guess invalid RSP opcode would be one of the only error messages left. So in a way, I actually don't want to fix this issue in RSP interpreter, because having that SP DMA error message can save us from having ear wrecks (not completely though in my experience -.-).

Still got to do whatever's necessary to fix.

from project64.

Confirmed and reproduced.
LLE GFX and Recompiler/Interpreter RSP. Happens a few seconds after the intro if you don't press start.

from project64.

closing old issue, if this is still an issue it can be reopened

from project64.