Subject: Re: [stella] 6502 basics: signed LSR From: Russ Perry Jr <slapdash@xxxxxxx> Date: Sun, 15 Feb 2004 13:18:15 -0600 |
At 8:10 PM +0100 2/15/04, Thomas Jentzsch wrote: >KirkIsrael wrote: >> Is there a better way of dividing a signed 1-byte integer >> by 2 than this? (which says, if var is positive, just do LSR, >> otherwise LSR and OR w/ -128 i.e. #%10000000 ) > Yup: > lda var > cmp #$80 > ror > sta var Ha ha... I was feeling silly enough after reading Eric's code, but this seals it. Back to lurking for ME I think. :-) -- //*================================================================++ || Russ Perry Jr 2175 S Tonne Dr #114 Arlington Hts IL 60005 || || 847-952-9729 slapdash@xxxxxxx [NEW!] VIDEOGAME COLLECTOR! || ++================================================================*// ---------------------------------------------------------------------------------------------- Archives (includes files) at http://www.biglist.com/lists/stella/archives/ Unsub & more at http://www.biglist.com/lists/stella/
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