Re: A86: FindPixel Routine

To: assembly-86@lists.ticalc.org
Subject: Re: A86: FindPixel Routine
From: Trent Lillehaugen <tllilleh@polymail.cpunix.calpoly.edu>
Date: Mon, 06 Apr 1998 18:56:39 -0700
Delivered-To: assembly-86-outgoing@towerguard.unix.edu.sollentuna.se
References: <19980407001357265.AAA232@intrepid>
Reply-To: assembly-86@lists.ticalc.org


    Yeah simple.  When you call FindPixel, HL returns with the memory address, and A returns the "mask".  the "mask" has the bit high that you were looking
for.. leave out your line
ld a,1
and everything will be alright.  When you set A to 1, you were putting in the binary number %00000001.. so it put the pixel on that is 8 (not 5) pixels over to
the right.

so after your FindPixel call this is what was set:
HL = $FC10
A  = %01000000
(i'm assuming the top-left is 0,0)
when you set A to %00000001 you actually wrote to (8,1)




Ricci E. Adams wrote:

> Could somebody please tell me what is wrong with this?  I am trying to put
> a pixel at (1,1) but it comes up around (5,0)
>                                                                                                                                                 - Thanks
>                                                                                                                                                 Ricci Adams
> #include "ti86asm.inc"
> .org _asm_exec_ram
>     ld e, 1
>     ld d, 1
>         call FindPixel
>     ld a,1
>     ld (hl),a

Trent Lillehaugen
Computer Engineering Major
California Polytechnic University, San Luis Obispo
<http://www.calpoly.edu/~tllilleh/a86/a86.html>
<mailto:tllilleh@polymail.calpoly.edu>

References:

A86: FindPixel Routine

From: "Ricci E. Adams" <ricci@chipsnet.com>

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