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Re: 65C02 unused opcodes (what they do)
- Subject: Re: 65C02 unused opcodes (what they do)
- From: guertinp@IRO.UMontreal.CA (Paul Guertin)
- Date: Wed, 10 Aug 1994 19:45:20 GMT
- Newsgroups: comp.sys.apple2
- Organization: Universite de Montreal, Canada
- References: <3243kb$2t2@harbinger.cc.monash.edu.au> <Cu7zqA.JzI@actrix.gen.nz> <328rnb$jh2@nexus.uiowa.edu>
- Sender: news@IRO.UMontreal.CA
In article <328rnb$jh2@nexus.uiowa.edu> mfischer@heinous.isca.uiowa.edu writes:
>In case you're interested in exactly what the unused opcodes do, here's
>what the NCR data sheet says:
>
>All are NOPs (reserved for future use).
>
>Op Code Bytes Cycles
>X2 2 2
Except for A2, which is LDX immediate on the 6502 and 65C02,
and 12, 32, 52, 72, 92, B2, D2 and F2, which are the indirect
mode of ORA, AND, EOR, ADC, STA, LDA, CMP, and SBC respectively.
Paul Guertin
guertinp@iro.umontreal.ca