, . /
VGA
G VGA EEE
EBEE EE E EQEK E@E
@LH E EEEEEL IEDOS
E DE @ E L EE
E
: INPUT STATUS REGISTER ONE
: 3BAh Monochrome Mode Read Only
3DAh Color Mode Read Only
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INPUT STATUS REGISTER ONE
Ĵ
BIT 7 6 5 4 3 2 1 0
Display Enable
Light Pen Strobe
Light Pen Switch
Vertical Retrace
Diagnostic 1
Diagnostic 2
Not Used
DISPLAY ENABLE:
D0
1 ӁE ,EEECEE
EGC @BE E E
EEE
E ulti Function Video Controller
E EGEvideo RAM, EE
@M video RAM EE EGE
EEE, D EEE
E C@BE@
[@G]
LIGHT PEN STROBE:
D1
1 ӁE,
EMEEEE
ABEE.
0 ӁE, EEEEABEE
ED EEGE
LIGHT PEN SWITCH:
D2
1 ӁE, EEEE BEE
ERE
0 ӁE, EEEE ABEE
ERE
VERTICAL RETRACE:
D3
1 ӁE
, ERT E
EKE @BE E EE
0 ӁE, ECRT EEKE
E.
DIAGNOSTIC 1,0:
D5 D4 E C Ecolor
output BEEQEE ED5 ED4
Color Plane Enable BE
EQEE@EE EEEolor Output
EEE.
Color Plane Input Status
Register Register One
D5 D4 D5 D4
0 0 Red Blue
0 1 S.Red S.Green
1 0 S.Blue Green
1 1 Not Used Not Used
.
SEQUENCER:
: EGA SEQUENCER INDEX
: 3C4h Write Only
Ŀ
EGA SEQUENCER INDEX
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