Re: LZ-Adv: vid_mem ques.


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Re: LZ-Adv: vid_mem ques.



Mark D Lippmann wrote:
> 
> I use (point on) and (point off) regularly in programs, but I was
> wondering if there is a way to load info. directly into the vid mem. I
> have at least 8 questions on how to go about doing that I will ask them
> if I need to, but can someone just explain how to do it?
> 
> So my question is:
> 
> How do you directly access the video memory to create graphics?
> 
> Thanks.
> 
> .\\ark


The video memory is in the last section of memory, from FC00 to FFFF, 
1024 bytes.  To access it, just load stuff to it like you would any other 
immediate data,  fro example:
	ld a,%10101010	;this is binary, checkerbord like pattern
	ld ($FC00),a	;puts A into $FC00, which is the top left 8 	
			;pixels on teh screen
you oculd go like this:
	ld hl,$FC00		;puts $FC00 into hl as pointer
	ld (hl),%10101010	;ld checkerboard into memory


I don't know which is better in the way of clock time, probably not much 
though


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