Aw: Re: [stella] Bit flip

Subject: Aw: Re: [stella] Bit flip
From: cybergoth@xxxxxxxx
Date: Mon, 10 Sep 2001 11:00:20 +0200 (CEST)
Hi Andrew!

> Table-lookup, 256 bytes.  Index your original value to get the bit-flipped
> value :)
> Somehow I think that's not what you were asking.

Uh... something like that was asked for?
Hm... straightforward I'd say a loop like this:

     LDX #$07
     LDA value
loop ROR
     ROL value
     DEX
     BPL loop

should do...

For the table:
Since only 1 bit is set, some memtable wouldn't need to waste a whole
page, something like this'd be enough:

ORG FX01

.byte $80

ORG FX02

.byte $40

ORG FX04

.byte $20

and so on... messes up the page, but leaves room for 
another 248 bytes :-)

Greetings,
     Manuel



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