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gbdev / gb-opcodes

https://gbdev.io/gb-opcodes/optables/
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Rotate `A` register instructions Z flag is incorrect #13

Closed 64kramsystem closed 3 years ago

64kramsystem commented 3 years ago

According to the GameBoy CPU Manual (but this is also verifiable by comparing with the general-register counterparts, e.g. RLC r), when performing a rotation (through carry or not) on the A register, the Z flag is set according to the result; currently, it's described as being reset.

Instructions: RRA, RLA, RRCA, RLCA.

avivace commented 3 years ago

Current descriptions are correct. Please check with emulators and ignore that document