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Re: BRUN HGR pics?
- Subject: Re: BRUN HGR pics?
- From: dastar@crl.com (Sam Ismail)
- Date: 1996/10/04
- Newsgroups: comp.sys.apple2
- Organization: CRL Dialup Internet Access (415) 705-6060 [Login: guest]
- References: <52n4g6$aab@cello.gina.calstate.edu> <52sp07$jvp@login.freenet.columbus.oh.us>
Dave Althoff (dalloff@freenet.columbus.oh.us) wrote:
: 1FF1- 48 PHA
: 1FF2- AD 50 C0 LDA $C050
: 1FF5- AD 52 C0 LDA $C052
: 1FF8- AD 54 C0 LDA $C054
: 1FFB- AD 57 C0 LDA $C057
: 1FFE- 68 PLA
: 1FFF- 60 RTS
: The PHA and PLA instructions are optional; I use them to make sure that
: the program doesn't scramble the A register.
You could've eliminated the PHA and PLA by using the BIT opcode (or
even STA) instead of LDA (the hex code is $2C I believe).
ie...
BIT $C050
BIT $C052
etc.
--
Sam
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