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Bytes and cycles for prefix opcodes

Open tobiasvl opened this issue 4 years ago • 2 comments

Some people (on the emudev Discord server) seem to be confused by the fact that the table lists 0xCB as 1 byte and 4 cycles, while all the 0xCB-prefixed opcodes in the separate table add that 1 byte and those 4 cycles to their totals.

For example, RLC B at 0xCB 0x00 is listed as taking 2 bytes and 8 cycles, but in the main table PREFIX at 0xCB is listed as taking 1 byte and 4 cycles.

That's not incorrect per se, since fetching the 1-byte prefix takes 4 cycles, so I'm not sure what the best "solution" would be. Perhaps just a footnote?

tobiasvl avatar May 25 '20 08:05 tobiasvl