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Re: 6502 illegal opcodes questions
- Subject: Re: 6502 illegal opcodes questions
- From: Scott Hemphill <hemphill@hemphills.net>
- Date: 25 Apr 2006 14:41:28 -0400
- Newsgroups: comp.sys.cbm, comp.sys.apple2, rec.games.video.classic
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Linards Ticmanis <ticmanis@gmx.de> writes:
> Thanks for all your helpful replies, which are going to find their way
> into an AppleWin improvement soon, if all goes well.
>
> I'm still not quite happy with some ugly details that I haven't seen
> documented too well:
>
> 1.) Operation of ARR ($6B) when the decimal flag is SET.
>
> 2.) Exact operation of decimal mode ADC and SBC in both the 6502 and
> the 65C02.
I have C code which emulates ADC and SBC for the 65C02 for all values of
the argments and flags.
>
> I'll take a look at the VICE code first. Do you know of any other GOOD
> code for this?
>
> Best wishes,
> --
> Linards Ticmanis
--
Scott Hemphill hemphill@alumni.caltech.edu
"This isn't flying. This is falling, with style." -- Buzz Lightyear