The most famous processor bug in the famous Mostech 6502 processor is the bug that hinders indirect jumping. This bug is apparently also present in newer incarnations of 6502 for bug-for-bug compatibility.

6502 has indirect jump operation. It's expressed as JMP (address), so JMP ($C000) would first fetch the target address from $C000 (low byte) and $C001 (high byte), then jump to that address.

However, 6502 is buggy what comes to page boundary: if we were to do JMP ($C0FF), the high byte will not be fetched from $C100 as expected, but from $C000!

So, beware of the edges of the pages, lest you get cuts to your fingers...

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