demo game cpu and ppu debug dump

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demo game cpu and ppu debug dump
by on (#11134)
a whilo ago i when i ws debugging my cpu quietust and blargg posted a cpu dump of nestest which helped out alot in debugging my cpu. i was thinking it might benefit everyone if we could post more of that on the main page. maybe some one could post some of the demo's cpu and ppu debugging info ? like cpu registers, reads, and writes and likewise with the ppu ? parhaps from nintdulator and from the nes with a data/address reader ? that way i can watch what works and see what fails on mine ?

any comments on this idea ? i think a few people here have a test cartrige to load and the device to record the nes hardware.

thanks

matt

by on (#11138)
Err, why have you not tried running Nintendulator on your computer under debug mode?

by on (#11142)
nintendulator is a windows only application. useless. i have been windows free for about 5 years now.

matt

by on (#11143)
Are you also x86-free? If not, have you tried Nintendulator in Wine or another independent implementation of the Windows API? This thread from a year ago claims that Nintendulator works in Wine with sound turned off.

by on (#11144)
I think that trying to debug things only by comparing logs is going to be an inefficient way of going about it. I've found this useful in only a few cases, due to the extreme volume of data to compare.

by on (#11150)
sometimes the large amount of data can be overwhelming. i was thinking for some of the smaller demos and test it would be usefull. i was thinking a bus dump from an actual nes and perhaps internal registeres from a working emulator.

few demos i thought would be usefull

scanline.nes
nestest.nes (like posted in the forums a while ago)
nestress.nes (dump for each test)
copper.nes

part would be to help my with my emulator but also see whats happening on the nes itself.

thanks

matt

by on (#11287)
i am at the point where i am perfecting my cpu and timing. here is a good application of an nes dump for nestest.nes. i could use it to check my clock cycle timing, reads, writes, etc......

how hard is it to set that up. copy a game (nestest.nes) to the test rom board and record the cartride bus?

who has these anyway?

how hard is it to get (or make), perhaps i could do this on my own and post here if anyone was interested ?

matt

by on (#11298)
I can't answer your question, but I do know of a good emulator timing test, called 'pputime2', available here: http://www.tripoint.org/kevtris/mappers/incoming/

You'll have to initialize NES RAM to $00 (normally it's $FF) to make it run correctly.