Re: A85: Conversion from 82


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Re: A85: Conversion from 82




the VIDEO_MEM on the 82 was erroneously called "GRAPH_MEM", when in fact,
there's TWO "GRAPH_MEM" locations, one for video, one for graphing.

the original 82 asm people state that it's called GRAPH_MEM because there
really isn't any video mem on it, just a buffer that a programmer must
manually call the display controller.

as for doing any porting to the 85 from the 82, just replace all
"GRAPH_MEM" with "VIDEO_MEM".  plus, you'll have to fix any "new line"
commands, like moving the video pointer to the correct spot (add hl,12
would be add hl,16)

in the extra 32x64 pixels you can put status and other stuff.

btw, what prog?

-Greg

EMAIL: l0rdg0at@juno.com; lordgoat@somethingorother.com;
l0rdg0at@hotmail.com; milewskg@stuy.edu
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On Sun, 18 Oct 1998 20:34:01 GMT mgp4007@omega.uta.edu (Michael Pearce)
writes:
>
>don't most ti82 games use a call DISP_GRAPH (or something like that).
>it copies from the GRAPH_MEM to the display.  you could just write
>your own DISP_GRAPH routine which could map the 82 screen to the 85
>(i.e copy 96 pixels for each row like on the 82 instead of 128 like on
>the 85).  maybe something like this (have no idea how correct this
>is):
>
>DISP_GRAPH:
> ld a,64		; 64 rows of video on both 85 and 82
> ld b,0			; b is always 0
> ld hl,GRAPH_MEM	; copy from GRAPH_MEM
> ld de,VIDEO_MEM	; copy to VIDEO_MEM
>D_Gloop:
> ld c,12		; bc = 12 bytes of video/row on 82
> ldir			; copy 1 row to the VIDEO_MEM
> inc de \ inc de	; \ 16 bytes of video on 85 so
> inc de \ inc de	; /  move to next row of video
> dec a			; one less row to copy
> jr nz,D_Gloop
> ret
>
>-mike pearce
>
>On Sun, 18 Oct 1998 15:56:51 -0400, you wrote:
>
>>
>>Does anyone know the easiest way to convert from an 82 to 85 display?
>>
>>
>
>

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