Re: A83: inc (HL) on the TI83
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Re: A83: inc (HL) on the TI83
I think that the problem is that "inc (hl)" is making the sprite you are
trying to display out of bounds.
a common example is this code for moving a sprite to the bottom:
down:
ld a,(yPos)
cp 56
ret z
inc a
ld (yPos),a
ret
the above code stops the motion of the sprite, before you display it off
of the screen and corrupt the system memory.
down:
ld hl,yPos
inc (hl) ; no bounds checking
ret
of course the larger one that uses the accumulator (reg A) is preferred.
-harper
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