Re: A85: Mapping Routine

To: assembly-85@lists.ticalc.org
Subject: Re: A85: Mapping Routine
From: Jes247@aol.com
Date: Sun, 27 Jul 1997 22:04:45 -0400 (EDT)
Reply-To: assembly-85@lists.ticalc.org

here's what I have in my source code. Take a look at it and see if you know
what's wrong. I don't get any errors when I compile it, only when I run
it...I'm stumped!

Width      = 8
Height     = 8
Total      = 96
NextYAt    = 96

 ld a,4
 out (5),a
 ld hl,Map1
 push de
 ld de,(PROGRAM_ADDR)
 add hl,de
 pop de
 ld (MapPointer),hl

DrawMap:
 ROM_CALL(CLEARLCD)
 ld a,Total
 ld (Current),a
 ld a,0
 ld (DrawMapX),a
 ld a,8
 ld (DrawMapY),a
DrawMapLoop:
 ld hl,(MapPointer)
 ld a,(Current)
 ld d,a
 ld a,Total
 sub d
 ld d,0
 ld e,a
 add hl,de
 ld a,(hl)
 ld hl,SpriteTable
 push de
 ld de,(PROGRAM_ADDR)
 add hl,de
 pop de
 add a,a
 ld d,0
 ld e,a
 add hl,de
 ROM_CALL(LD_HL_MHL)
 ld de,(PROGRAM_ADDR)
 add hl,de
 ld a,(DrawMapY)
 ld c,a
 ld a,(DrawMapX)
 ld b,a
 CALL_(PutSprite)
 ld a,(DrawMapX)
 add a,Width
 cp NextYAt
 CALL_Z(UpdateMapY)
 ld (DrawMapX),a
 ld a,(Current)
 ld b,a
 dec a
 ld (Current),a
 djnz DrawMapLoop
 ret

UpdateMapY:
 ld a,(DrawMapY)
 add a,Height
 ld (DrawMapY),a
 ld a,0
 ret