Re: A83: Question
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Re: A83: Question
In a message dated 12/06/98 1:26:38 AM, matthews@tkb.att.ne.jp writes:
>> 1. (pencol) & (penrow), Which is X and which is Y?
>
>Column...so x.
>Row......so y.
Ok, I thought I knew that, but do certain commands switch it? :\ Like the
'_vputs' routine, I've been confused by before, and it uses opposite
coordinates than the line routines, even though they dont use (pencol) and
(penrow)... =P
>> 2. Doing this...
>> ld hl, X*256+Y ;Is the 'h' loaded with X, and 'l' loaded with Y?
>> ld (pencol), hl ;But now 'l' is at (pencol)? LSB or something?
>
>Nah, to move X over to h you must multiply it by 100h right? 100h = 256d.
Same thing, Right? I use 256 cuz Most other people do... =P And Im pretty
sure thats the correct syntax for loading a 16 bit num in one step. Oh ya,
'In Decimal', is probably the keyword there, thats why it is 256. I was just
keeping consistent in number bases because I wouldnt come out with my screen
coordinates in Hex... =P
>H would go into pencol, and l to penrow...wait, I think you'd do:
> ld (penrow),hl
>
>HTH,
>James.
Dude, that just confused the hell out of me... I was under the impression
that the 'reverse byte loading' happens here, and involves MSB and LSB like
so...
pencol = 8252h / penrow = 8253h
ld (pencol), hl ;Now, 'l' is at 8252 and 'h' is at 8253...?
--Jason K.