Less bytes (just!), more cycles...
lda var
asl a
ror var
"Efficient" can mean different things, so the above may be useful, too :)
Cheers
A
----- Original Message -----
From: "Thomas Jentzsch" <tjentzsch@xxxxxx>
To: <stella@xxxxxxxxxxx>
Sent: Monday, February 16, 2004 6:10 AM
Subject: Re: [stella] 6502 basics: signed LSR
> 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
>
> Have fun!
> Thomas
> _______________________________________________________
> Thomas Jentzsch | *** Every bit is sacred ! ***
> tjentzsch at web dot de |
>
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