Disassembly tools - non '2600 but 6502 - important archiving work pls help

[+Andrew Davie]

I'm wondering what '2600 skills we can bring to the party to help with the above.  Essentially a one-of-a-kind ROM (6502) has been corrupted during dumping (bits 6 and 1 on all bytes) and subsequently lost. Shocking.  A friend of mine has shared the dumps and asked if we can reconstruct the 6502 code. I thought/hope that some '2600 enthusiasts could perhaps help with this, or failing that point me to the best resource we have for 6502 disassembly which I figure would be a good starting point for this task. Consider it a personal favour, if you will - if I've helped you out at some point... I'd really like to see our community come together to help out here.