I use the carry flag in a lot of z80 assembly for communicating a status of an o... | Hacker News

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lochnessduck 3 months ago | parent | context | favorite | on: XOR'ing a register with itself is the idiom for ze...

I use the carry flag in a lot of z80 assembly for communicating a status of an operation. XOR doesn’t mess with the carry flag, I think it’s another point in favor of xor. (Though I don’t remember even considering using sub)

Jare 3 months ago [–]

This is the exact reason I remember from back in the 80's. Perform arithmetic, clear register, CF is still valid.

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