Re: LZ: What is wrong with this routine?


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Re: LZ: What is wrong with this routine?



Min Idzelis wrote:
> 
> This is a line drawing routine someone gave to me. However, it always
> ends unexpectently, that is, it gives me a TI-Basic ERROR 14
> UNDEFINED, and when i press [F5] QUIT it fills the screen with black
> dots. After you press CLEAR it goes away and everything works again.
> I'll post the ASM test program here: (I'm self teaching code, BTW)
> 
> #include "TI-85.H"
> 
> .org 0
> .db "test",0
> 
> BlackScreen:
>  ld hl, $FC00
>  ld d, h
>  ld e, l
>  inc de
>  ld (hl), $FF
>  ld bc, 1023
>  ldir
> test:
>  ld c, 30
>  ld b, 10
>  ld d, 20
> 
> HorzLine:
>  ROM_CALL(FIND_PIXEL)
>  ld b, d
>  ld c, a
>  ld de, $FC00
>  add hl, de
> HRep:
>  ld de, 0
>  ld a, c
>  or (hl)
>  ld (hl), a
>  ld a, c     ; Skip these three lines
>  xor (hl)   ; if you want to fill
>  ld (hl), a  ; instead of erase
>  rrc c
>  adc hl, de
>  djnz HRep
>  ret
> 
> Wait2:                          ; wait for any key
>  call   GET_KEY
>  cp     0
>  jr     z, Wait2
>  ret
> 
> .end
>      Computers are like drugs: Highly addictive,
> incredibly expensive, and you keep having to buy more
> and better to remain at the same level of amusement.
you forgot to put in 
	ld a, 4 
	out (5),a


I had that same problem before and that is what caused it. also memory
was added to the equation memory.
PCoMP
Visit Maximus Productions home page at: http://www.ntsource.com/~pcomp
IRC Name: Rob_Zombie


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