N64 OP Codes? N64 Tracer?

gukingofheart

Well-Known Member
OP
Member
Joined
Feb 2, 2022
Messages
235
Trophies
0
Age
124
XP
455
Country
United States
Know a website with the OPcode values? Here's one for the NES & SNES
http://www.6502.org/tutorials/6502opcodes.html
https://undisbeliever.net/snesdev/65816-opcodes.html

But I need one for the N64 with the numbers.
Do you know what 2400 means, I notice many different codes use this. is it a LDA? A NOP?


I have "Project64-v2.4.0-1688-ge230133", which has a debugger. Do you know if this emulator has a tracer or not? Or if I need some other emulator when it comes to tracing?
Tracing means, seeing all the debug data that ran before.


Any help, would be appreciated!
 

gukingofheart

Well-Known Member
OP
Member
Joined
Feb 2, 2022
Messages
235
Trophies
0
Age
124
XP
455
Country
United States
datasheet for the CPU: https://datasheets.chipdb.org/NEC/Vr-Series/Vr43xx/U10504EJ7V0UMJ1.pdf


The CPU architecture the NEC VR4300 was modified from is the VR4200, which is modified from R2400.
Sure it's not a LDL, $24,3($0), or maybe it's a branch code.
Your sheet does not list the OPcodes, only the names.

Always Have 8 Red Coins On Bowser Levels
Action Replay/GameShark (this code uses a 2400, why?)
812F32E4 2400

Stepping Blocks Last Forever
Action Replay/GameShark (this code uses a 2400 & a 1000, why?)
812B18FC 2400
812B1904 1000

For NES & SNES, OPcodes have simple names like Load, Move, Copy, Branch.
 

bobmcjr

Well-Known Member
Member
Joined
Apr 26, 2013
Messages
1,156
Trophies
1
XP
3,277
Country
United States
Sure it's not a LDL, $24,3($0), or maybe it's a branch code.
Your sheet does not list the OPcodes, only the names.

Always Have 8 Red Coins On Bowser Levels
Action Replay/GameShark (this code uses a 2400, why?)
812F32E4 2400

Stepping Blocks Last Forever
Action Replay/GameShark (this code uses a 2400 & a 1000, why?)
812B18FC 2400
812B1904 1000

For NES & SNES, OPcodes have simple names like Load, Move, Copy, Branch.
These aren't necessarily writing opcodes. See this documentation on gameshark codes: https://en64.shoutwiki.com/wiki/Make_Nintendo_64_GameShark_Codes

The first code writes 0x2400 to address 0x2f32e4 constantly.

You'd need to check if this is overwriting code or just simply data. If it is overwriting code, keep in mind that N64 MIPS opcodes are 32-bit, so this 16-bit value would only be half an opcode, if it's even writing to an opcode. If it is, you'd need to find the full 32-bit value at that address (0x2f32e4) and either use a MIPS disassembler, or convert it to binary and read the ISA manual.
 

gukingofheart

Well-Known Member
OP
Member
Joined
Feb 2, 2022
Messages
235
Trophies
0
Age
124
XP
455
Country
United States
Duh to myself, for not debugging after the cheat code is enabled.

It's an "ADDU" R0 R0 code.
Is R0 always set to 0. I understand more now, at least.
I'll just experiment with debugging different values, and write down the patterns
 

Site & Scene News

Popular threads in this forum

General chit-chat
Help Users
  • BakerMan @ BakerMan:
    we're cooked, possibly literally
  • BakerMan @ BakerMan:
    if you have a habitable basement, the heat shouldn't be down there and that's where you should hang out
  • Sicklyboy @ Sicklyboy:
    No, but, the air conditioner in my living room gets fuckin icy
  • Sicklyboy @ Sicklyboy:
    In a good way, not as in a "my coils are freezing" kind of way
  • K3Nv2 @ K3Nv2:
    Not everyone lives in theirs mom's basement gosh
  • BakerMan @ BakerMan:
    nah, my mom's basement is just for the weekends to check in on the family
  • BakerMan @ BakerMan:
    i usually live in your mom's basement
    +1
  • BakerMan @ BakerMan:
    saves a lot of time fr
  • Sicklyboy @ Sicklyboy:
    It's 11:30 PM here, I just took the trash out and my god is it awful outside
  • Sicklyboy @ Sicklyboy:
    This heatwave can eat my ass
    +3
  • MysticStarlight @ MysticStarlight:
    omg same, it's VERY hot here, too
  • BakerMan @ BakerMan:
    fuck this heatwave, i don't usually sleep with a fan, but i believe the fan is getting put on the bed rather than beside it
  • BakerMan @ BakerMan:
    IT'S 12:30 IN THE FUCKING MORNING AND IT'S STILL 78°, WHAT THE FUCK?
    +1
  • NinStar @ NinStar:
    78º seems abnormal for any part of the day
  • BigOnYa @ BigOnYa:
    Yea it was 96 F for the high, 78 F for the low today, in Ohio, bout same for bakerman in Michigan
  • BigOnYa @ BigOnYa:
    F- fahrenheit C-Celsius. We in USA use F as our temp ratings
  • Sicklyboy @ Sicklyboy:
    F = Freedom units
    +2
  • HiradeGirl @ HiradeGirl:
    So... C = Cum units?
    +1
  • K3Nv2 @ K3Nv2:
    Clip units
  • SylverReZ @ SylverReZ:
    @HiradeGirl, That's how they get bigger loans at the bank.
    +1
  • HiradeGirl @ HiradeGirl:
    Welp.
    HiradeGirl @ HiradeGirl: Welp.