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Last updated on Oct-18-2019 Download

Preferred OpCodes

Preferred OpCodes
by on (#33371)
Hey, I'm writing an assembler/linker/dis set of programs that targets among other things the nes. What are the preferred opcodes for mnemonics that there are many possibilities for like nop?

Thanks

by on (#33373)
$EA is the official NOP, the other NOPs are not documented.

by on (#33374)
Gratci.

by on (#33376)
The other NOPs aren't official. They are documented, often called DOP (2-byte) and TOP (3-byte). See one of the documents about unofficial instructions (often erroneously called undocumented or illegal instructions). I don't think there's much opinion about how they are disassembled for NES, since they are rarely used by anything.