#Z80 question for experts even though I have a lot of experience with it: the Zilog manual says that the IX/IY offset is relative (signed) but I have _never once_ seen negative offsets used in the wild, e.g. `ld A, [IX-$20]`, I'm not sure all assemblers even support "-" instead of "+" in IX/IY instruction, mine doesn't yet and I'd prefer to confirm this with others first.
-- edit: answer in the replies; it is signed!
#retrocomputing #retrodev
Kroc Camen
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2025-06-27 11:41:15 UTC
Author Public Key
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wss://relay.momostr.pinkPublished at
2025-06-27 11:41:15 UTCEvent JSON
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"content": "#Z80 question for experts even though I have a lot of experience with it: the Zilog manual says that the IX/IY offset is relative (signed) but I have _never once_ seen negative offsets used in the wild, e.g. `ld A, [IX-$20]`, I'm not sure all assemblers even support \"-\" instead of \"+\" in IX/IY instruction, mine doesn't yet and I'd prefer to confirm this with others first.\n\n-- edit: answer in the replies; it is signed!\n\n#retrocomputing #retrodev",
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