Ah, I see!
I remember getting confused by some of the descriptions in the WDC 65C02 data sheet, like the way that the "Absolute" addressing mode is described as taking 4 cycles, but JMP with the "Absolute" addressing mode takes only 3.
I spent a bunch of time comparing the Synertek 6502 programming manual with the WDC's docs, and various "differences between 6502 and 65C02" descriptions to figure out what was actually going on, and compiled the result into a machine-readable table:
https://gitlab.com/Screwtapello/isa65xx/-/blob/68464350f4ec4414b956f25ea0d6fd8fd93531eb/opcodes_expected.tsv
(it doesn't have the Rockwell bit-twiddling instructions, or WDC's STP or HLT, though)
Screwtapello
npub18e…w5xqg
2025-07-20 08:31:56 UTC
in reply to nevent1q…8k57
Author Public Key
npub18eedjkzfyggqa7pwjpyn0xcj8wmh648hd0m8kmw4urc2n99ym0gs0w5xqgSeen on
wss://relay.momostr.pinkPublished at
2025-07-20 08:31:56 UTCEvent JSON
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