Understanding 6502 assembly on the Commodore 64 - (12) Recap and Beginning Registers

Throughout our program, we have used relatively easy math to allow us to achieve our goals, this has primarily been accomplished with four operations. INX, INY, DEX, DEY.  This is the simplest form of addition and subtraction on the 6502, and its easy to understand.  You might have noticed as well that so far we have not only avoided writing code to NMI's or IRQ's, we have shown complete disregard for our status registers, a most important part of our processor.


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