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- The Sierra SC11486 RAMDAC is an alternative RAMDAC for use with
- the Tseng 4000 and ATI VGA Wonder XL.
-
- It provides 15 bit RGB with 5 bits for each basic color.
-
- When in HiColor mode each pixel occupied two bytes.
-
- Bits 0- 4 of the pixel is the blue component.
- 5- 9 of the pixel is the green component.
- 10-14 of the pixel is the red component.
-
-
- This works for Tseng ET-4000 systems:
-
-
- function sethicolor(mode:word);
- var rp:registers;
- begin
- sethicolor:=false;
- rp.ax:=$10f1;
- intr($10,rp);
- if (rp.ax=$10) and (rp.bl=1) then
- begin
- rp.ax:=$10f0;
- rp.bl:=mode; {or another video mode.}
- intr($10,rp);
- if rp.ax=$10 then
- begin {now in HiColor mode.}
- sethicolor:=true;
- end;
- end;
- end;
-
- procedure plot(xcoor,ycoor,red,green,blue:word);
- var l:longint;
- begin
- l:=(longint(640)*ycoor+xcoor)*2;
- port[$3cd]:=l shr 16;
- memw[$a000:(l and $ffff)]:=blue+(green shl 5)+(red shl 10);
- end;
-
-
-
-
-
- BIOS extensions (Tseng 4000 Sierra HiColor DAC):
-
- ----------1010F0-----------------------------
- INT 10 - VIDEO - Tseng ET-4000 BIOS - SET HiColor GRAPHICS MODE
- AX = 10F0h
- BL = video mode (see also AH=00h)
- 32768-color modes:
- 13h = 320x200
- 2Dh = 640x350
- 2Eh = 640x480
- 2Fh = 640x400
- 30h = 800x600
- Return: AX = 0010h if successful
- other on error
- Note: the Tseng HiColor BIOS extensions are supported by:
- Diamond Computer Systems SpeedStar HiColor VGA
- Everex Systems HC VGA
- Focus Information Systems 2theMax 4000
- Cardinal Technologies VGA732
- Orchid ProDesigner IIs
- SeeAlso: AX=10F1h
-
- Note: Not all BIOS versions support all of these modes!!
- ----------1010F1-----------------------------
- INT 10 - VIDEO - Tseng ET-4000 BIOS - GET DAC TYPE
- AX = 10F1h
- Return: AX = 0010h if succesful, errorcode if not
- BL = type of digital/analog converter
- 00h normal VGA DAC
- 01h Sierra SC1148x HiColor DAC
- else other HiColor DAC
- SeeAlso: AX=10F0h