Disassemble some 6502 code

[davideo]

I need to disassemble a 6502 ROM image but I haven't got a 6502 machine anymore

Does anybody know of a good 6502 disassembler that will allow me to load a file, give it a start address and disassemble from that point onwards?

Either PC or Amiga.

Thanks

 

[TheCorfiot]

You can use an emulator and associated utility ti disassemble the code.
Maybe BeebEm

 

[kisiel]

I need to disassemble a 6502 ROM image but I haven't got a 6502 machine anymore

Does anybody know of a good 6502 disassembler that will allow me to load a file, give it a start address and disassemble from that point onwards?

Either PC or Amiga.

Thanks

http://sourceforge.net/projects/dis6502/

you're welcome

 

[davideo]

@kisiel

Thanks.

I've downloaded dis6502 and will give that a go.

@TC

I'm trying to write an emulator and need to disassemble the keyboard ROM routines in the original monitor ROM to see how they work

 

[kisiel]

rolling zero or rolling one with debouncing , on lda sta cmp and IRQ.

 

[davideo]

Don't think it's that easy.

Set the Row and Scan the column on this keyboard then AND and a few other commands to get the key pressed.

 

[Beavis]

Think I've got the C-64 kernel routines somewhere, so you only need to change some addresses, and Bob's your uncle.

 

[kisiel]

idea is to find pressed key in row / column so you need to roll zero or one in 8 bit port and read second port. Of course it is more complicated if you decide to read joy in port 2


and if you want to make hardware keyboard emulation you have few cycles to do it sta lda.



and please use AAY64

 

[davideo]

Thanks guys.

Although it's an 8 bit machine it's not Commodore

 

[Beavis]

The opcodes are the same though..

 

[demolition]

Yeah, you can even load the file into some C64 emulator like VICE, open its monitor and single-step through the code, as long as it does not rely on other hardware than the CPU. For the keyboard memory addresses, if they are located in the C64's RAM area, you can put whatever you want in there yourself to emulate certain keypresses.

 

[protek]

Try CBM Prg Studio. It's a Windows IDE for developing Basic or Assembly programs.