A83: demo that moves a sprite around the screen

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A83: demo that moves a sprite around the screen


For the heck of it, here's code that moves a sprite around the screen:

GDown = 01h
GLeft = 02h
GRight = 03h
GUp = 04h
GClear = 0Fh

tTitle: .db "DEMO",0

xpos = saferam3
ypos = xpos+1
lblStart:
  ;Position sprite at 16,16
  ld hl,$1010
  ld (xpos),hl
Loop:
  call DrawSprites
  bcall(_grbufcpy)
  bcall(_cleargbuf)
  call WaitKey
  cp gClear
  ret z
  cp gLeft
  jr z,Left
  cp gRight
  jr z,Right
  cp gUp
  jr z,Up
  cp gDown
  jr z,Down
  jr Loop
Left:
  ld a,(xpos)
  sub 4
  jr c,Loop
  ld (xpos),a
  jr Loop
Right:
  ld a,(xpos)
  add a,4
  cp 96-8
  jr nc,Loop
  ld (xpos),a
  jp Loop
Up:
  ld a,(ypos)
  sub 4
  jp c,Loop
  ld (ypos),a
  jp loop
Down:
  ld a,(ypos)
  add a,4
  cp 64-8
  jp nc,Loop
  ld (ypos),a
  jp loop
DrawSprites:
  ld a,(xpos)
  ld b,8
  ld hl,(ypos)
  ld ix,smiley
  jp ionputsprite

WaitKey:
  ei
WaitKeyLoop:
  halt
  bcall(_getcsc)
  or a
  jr z,WaitKeyLoop
  ret


smiley:
  .db %00111100
  .db %01000010
  .db %10100101
  .db %10000001
  .db %10100101
  .db %10011001
  .db %01000010
  .db %00111100



>From: Sk8a4good@aol.com
>Reply-To: assembly-83@lists.ticalc.org
>To: assembly-83@lists.ticalc.org
>Subject: A83: Sprite Routine 83+
>Date: Sun, 14 Jan 2001 13:54:09 EST
>
>
>I have started programming asm for the 83+, and I can do the basics like 
>shut
>off the calc, use get key and compare to jump to a label, but I cant seem 
>to
>find an 83+  (MUST BE 83+) sprite routine.  All I want is a small piece of
>code that moves a sprite left, right, up and down.  Can somebody help me 
>out?
>

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