Re: A82: Re: Question...
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Re: A82: Re: Question...
IX would work, but if you are looking for optimization, loading the index
register isn't the way to go. Loading anything to IX takes 4 bytes and 20
ticks, and SET and RES are both 4 bytes/23 ticks (when using the index
register). Your HL suggestion is better, the instructions take up half of
the space.
Rob
At 07:53 PM 3/6/98 +0100, you wrote:
>
>Just declare the var as:
>RowVar:
>.DB 0 ; define 8 bits
>Then load IX with a pointer to the var:
>LD IX,RowVar
>Then you can just use RES b,(IX+$0) and SET b,(IX+$0) to reset/set bits
>(just replace b with the number of the bit). Instead of using IX you can
>use HL too, just do something like this
>
> LD HL,RowVar ; Point to the vars
> SET 1,(HL) ; Bit 1 = 1
> RES 2,(HL) ; Bit 2 = 0
>
>DInes
>-----Original Message-----
>From: A. El-Helw <ahmedre@worldnet.att.net>
>To: assembly-82@lists.ticalc.org <assembly-82@lists.ticalc.org>
>Date: 5. marts 1998 22:19
>Subject: A82: Question...
>
>
>>
>>Hello Everyone,
>> I am going to start a new project [actually, I have already :] and I
>have
>>a question... suppose I wanted to store 8 numbers [either 1 or 0] in a
>>variable.. could I do this? I think you can do it with bits and bytes
>but
>>I don't know how really :P Is this possible, or could someone show me an
>>easier way??
>>
>>RowVar: .db 0,0,0,0,0,0,0,0
>>
>>ld hl,1
>>ld (RowVar),hl ;Load? all of RomVar Numbers as 1????
>>
>>ld hl,0
>>ld (RomVar+8),hl ;Load? 0 into RomVar+8 [the 8th #???]
>>
>>ld hl,(RomVar+7) ;Load ??? The seventh number into hl?
>>
>>
>>Ok, so hopefully someone will understand what I am trying to ask :P
>Thanks...
>>
>> -Ahmed
>>Ahmed El-Helw
>>ahmedre@worldnet.att.net
>>http://asm86.home.ml.org
>>http://asm8x.home.ml.org
>>Ahmed_ on IRC
>>ICQ UIN: 3350394
>>
>
>_______________________________________
>
>Dines Justesen
>Email: dines@post1.com or
> c958362@student.dtu.dk
>WWW : http://www.gbar.dtu.dk/~c958362/
>_______________________________________
>
>
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