[reaperducer]

title should really be named "Dirty tricks C64 6502 programmers use".

In that case, probably Dirty Tricks 6510 Programmers Use would be even better.

[vidarh]

While that may be technically correct, the programmer-visibile difference between the MOS 6502 and the MOS 6510 is totally incidental in this case - the 6510 has a a built in 6/8-pin IO port (partially used for bank switching the ROMs in the C64). Unless you touch the IO ports, they should behave identically, down to the cycle timings of instructions and the same behavior of undocumented opcodes.

In this case, the real C64 specific tricks are not 6510 specific, but depending on the specific initialization done by the C64 ROM and calling C64 ROM routines.

[tenebrisalietum]

A real "dirty trick" is reading the actual RAM in memory locations 0 and 1 on the 6510 (and not the I/O port values).