Re: A85: Contrast + More


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Re: A85: Contrast + More




At 07:08 PM 2/26/98 EST, you wrote:
>
>How do you increase/decrease the contrast of the screen (Usgard)? 
>
>I tried:
>
> ld a,CONTRAST
> inc a
> inc a
> inc a
> ld (CONTRAST),a
>
>It didn't work.  What works?

the port that handles the contrast (2) does the actual contrast changing.
However, the port is write only.  You have to do

	ld a,(CONTRAST)
	inc a
	inc a
	inc a
	ld (CONTRAST),a
	out (2),a
	



>
>Also, after my program (Usgard) runs and I go to the graph screen after
>exiting Usgard, the stuff that was on the screen is still there.  How do I
fix
>that?
>(I am saving to the GRAPH_MEM, and loading it into the VIDEO_MEM.
>
>I tried:
>
>  call CLEARLCD
>  ld hl,$8641
>  ld (hl),$0
>  ld bc,1024-1
>  call OTH_FILL
>  ret
>
>
>Thanxx for the help (hopefully)  :)
>
>

the easiest way I do this is with no calls at all (CLEARLCD will still work)

	ld hl,$8641
	ld de,$8642
	ld bc,$0400
	sub a
	ld (hl),a
	ldir


-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
 Alan Bailey            mailto:bailela@charlie.cns.iit.edu
 IRC:Abalone              Web:http://www.iit.edu/~bailela/
-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
 


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