Table des matières

INT 0x10 - 0x12 - Video Subsystem Configuration (EGA/VGA)

Request/Call:

reg value descr
AH 0x12
BL see bellow sub system

0x10 - return video configuration information

reg value
AH 0x12
BL 0x10

Return:

BH descr
0 color mode in effect
1 mono mode in effect
BL descr
0 64k EGA memory
1 128k EGA memory
2 192k EGA memory
3 256k EGA memory
CH feature bits
CL switch settings

0x20 - select alternate print screen routine

reg value
AH 0x12
BL 0x20

0x30 - select scan lines for alphanumeric modes

reg value Descr
AH 0x12
BL 0x30
AL 0x00 200 scan lines
0x01 350 scan lines
0x02 400 scan lines

return

Reg Value
AL 12

0x31 - select default palette loading

reg value Descr.
AH 0x12
BL 0x31
AL 0x00 enable default palette loading
0x01 disable default palette loading

return

Reg Value
AL 12

0x32 - CPU access to video RAM

reg value Descr.
AH 0x12
BL 0x32
AL 0x00 enable CPU access to video RAM and I/O ports
0x01 disable CPU access to video RAM and I/O ports

return

Reg Value
AL 12

0x33 - Gray scale summing

reg value Descr.
AH 0x12
BL 0x33
AL 0x00 enable gray scale summing
0x02 disable gray scale summing

return

Reg Value
AL 12

0x34 - cursor emulation

reg value Descr.
AH 0x12
BL 0x34
AL 0x00 enable cursor emulation
0x01 disable cursor emulation

return

Reg Value
AL 12

0x35 - PS/2 video display switching

reg value Descr.
AH 0x12
BL 0x35
AL 0x00 initial adapter video off
0x01 initial planar video on
0x02 switch active video off
0x03 3 switch inactive video on
ES:DX pointer to 128 byte save area (when AL = 0, 2 or 3)

return

Reg Value
AL 12

0x36 - video refresh control

reg value Descr.
AH 0x12
BL 0x36
AL 0x00 enable refresh
0x01 disable refresh

return

Reg Value
AL 12

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