6502 Core Testing

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6502 Core Testing
by on (#22787)
Is there a good piece of 6502 code somewhere I can load to test a 6502 core that I wrote? (without messing with the PPU)

I'm writing an NES emulator from scratch, mostly as for the 'fun' experience. I think I've finished the CPU core but I just know there's a bug I haven't found... By constantly setting the vblank bit I can watch Super Mario Bros run and it looks like it is running correctly, but I'd like to run a program where I can confirm the core is working by checking the end values of the registers or something to that effect so I can get rid of the bugs from the CPU before I worry about anything so complex as the PPU :)

I guess the best option would be to not be lazy and write it myself, but... meh :lol:


EDIT: Found Nestress.nes, which requires the PPU and IO to be somewhat functional to get to the tests... and found references to nestest.nes which I couldn't find many details about. If there were some generic code that didn't depend on the PPU that would be ideal, otherwise I guess I'll just try implementing the PPU then test with Nestress.nes

by on (#22791)
nestress is old.

Here is a list of test ROMs.

by on (#22796)
nestest sounds like exactly what I want, unfortunately the link to it on that wiki page returns a 404 and I can't find another copy on Google... anyone have one?

EDIT: found the ROM, but I'd like a copy of the readme file if anyone out there has one...

EDIT: And it already helped me find a couple stupid errors I made in indexed indirect and indirect indexed... d'oh! :roll: