3B8h (W)
bit 1 Hercules graphics mode if set, text mode else
3 Video enabled if set
5 Blink enabled if set
7 Graphics page 1 displayed if set, page 0 else
3BAh (R) Status Register
bit 0 Horizontal sync
3 Video signal
7 Vertical sync
3BAh (W) Mode Select Register
bit 3 132-column text for monochrome
3BBh (W) Lightpen Strobe Reset
Writing to this register will clear the lightpen strobe.
3BFh (W)
bit 0 Setting of graphics mode bit (3B8h bit 1) enabled if set
1 Setting of graphics page bit (3B8h bit 7) enabled if set
ID Hercules Graphics Card:
old:=rdinx($3B4,$a);
outp($3B5,6); {Change Cursor End}
for x:=1 to 50 do; {Wait for CRTC to respond}
val:=inp($3B5);
outp($3B5,old);
if val=6 then
begin
x:=50000;
repeat
dec(x);
y:=inp($3BA);
until (y and $80)=0) or (x=0);
if x=0 then __MDA__
else
case y and $70 of
$50:Hercules Incolor;
$10:Hercules Graphics Plus
else Hercules Graphics Card;
end;
end;
Hercules GRAFIX BIOS Interface:
GRAFIX is a memory resident program, not a part of the Hercules Graphics Card.
----------1040-------------------------------
INT 10 - VIDEO - SET GRAPHICS MODE (Hercules GRAFIX)
AH = 40h
SeeAlso: AH=41h
----------1041-------------------------------
INT 10 - VIDEO - SET TEXT MODE (Hercules GRAFIX)
AH = 41h
SeeAlso: AH=40h
----------1042-------------------------------
INT 10 - VIDEO - CLEAR CURRENT PAGE (Hercules GRAFIX)
AH = 42h
SeeAlso: AH=45h
----------1043-------------------------------
INT 10 - VIDEO - SELECT DRAWING PAGE (Hercules GRAFIX)
AH = 43h
AL = page number (0,1)
SeeAlso: AH=44h,AH=45h
----------1044-------------------------------
INT 10 - VIDEO - SELECT DRAWING FUNCTION (Hercules GRAFIX)
AH = 44h
AL = drawing function
00h clear pixels
01h set pixels
02h invert pixels
SeeAlso: AH=44h,AH=46h,AH=4Ch,AH=4Dh
----------1045-------------------------------
INT 10 - VIDEO - SELECT PAGE TO DISPLAY (Hercules GRAFIX)
AH = 45h
AL = page number (0,1)
SeeAlso: AH=42h,AH=43h
----------1046-------------------------------
INT 10 - VIDEO - DRAW ONE PIXEL (Hercules GRAFIX)
AH = 46h
DI = x (0-720)
BP = y (0-347)
Note: function 44h determines operation and function 43h which page to use
SeeAlso: AH=0Ch,AH=47h,AH=49h,AH=4Ch,AH=4Dh
----------1047-------------------------------
INT 10 - VIDEO - FIND PIXEL VALUE (Hercules GRAFIX)
AH = 47h
DI = x (0-720)
BP = y (0-347)
Return: AL = 00h pixel clear
AL = 01h pixel set
Note: function 43h specifies which page is used
SeeAlso: AH=0Dh,AH=46h
----------1048-------------------------------
INT 10 - VIDEO - MOVE TO POINT (Hercules GRAFIX)
AH = 48h
DI = x (0-720)
BP = y (0-347)
SeeAlso: AH=49h
----------1049-------------------------------
INT 10 - VIDEO - DRAW TO POINT (Hercules GRAFIX)
AH = 49h
DI = x (0-720)
BP = y (0-347)
Note: function 48h or 49h specify first point, 44h operation and 43h
page to use
SeeAlso: AH=43h,AH=44h,AH=48h,AH=4Ch,P = y (0-347)
Note: unlike the other BIOS character functions character position is
specified in pixels rather than rows
DI = x coordinate of lower left corner
BP = y coordinate of lower left corner
BX = height in pixels
CX = width in pixels
Note: draws a solid rectangle
SeeAlso: AH=4Eh
----------104B-------------------------------
INT 10 - VIDEO - DISPLAY CHARACTER (Hercules GRAFIX)
AH = 4Bh
AL = character to display
DI = x (0-720)
BP = y (0-347)
Note: unlike the other BIOS character functions character position is
specified in pixels rather than rows and columns
SeeAlso: AH=09h,AH=0Ah
----------104C-------------------------------
INT 10 - VIDEO - DRAW ARC (Hercules GRAFIX)
AH = 4Ch
AL = quadrant (1 = upper right, 2 = upper left, et cetera)
DI = x coordinate of center
BP = y coordinate of center
BX = radius
SeeAlso: AH=49h,AH=4Dh
----------104D-------------------------------
INT 10 - VIDEO - DRAW CIRCLE (Hercules GRAFIX)
AH = 4Dh
DI = x of center
BP = y of center
BX = radius
SeeAlso: AH=49h,AH=4Ch
----------104E-------------------------------
INT 10 - VIDEO - FILL AREA (Hercules GRAFIX)
AH = 4Eh
DI = x coordinate of an interior point
BP = y coordinate of an interior point
Notes: fills convex polygonal areas
the first fill makes the figure solid, the second erases it
SeeAlso: AH=4A
