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by t0mek 2906 days ago
The table here: [1] is very accurate. I wasn't able to find any bug either in the cycle counts or the affected flags list during the Coffee GB [2] development.

[1] http://pastraiser.com/cpu/gameboy/gameboy_opcodes.html

[2] https://news.ycombinator.com/item?id=17134668
2 comments
abaines 2906 days ago
The table in [1] has 0 in the carry flag for the SRA instructions, is that correct? I thought they shifted the lowest bit into the carry same as SRL.
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qcoh 2906 days ago
I think you're right, see [0].

Furthermore E9 is not "JP (HL)" but rather "JP HL". If I remember correctly a few timings or instruction sizes are off as well.

[0]: http://www.devrs.com/gb/files/opcodes.html

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the_spacebyte 2906 days ago
Perfect, thank you. I've been using this image but only to cross-check the opcodes values and what they meant.
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