AXIOMTEK SBC84833 Series, User Manual

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SBC84833 Series All-In-One Capa Board User’s Manual
Digital I/O
73
Digital I/O has 8bits (DIO0~7). Every bit can be programmed input or
output and is set pull-high with +5V level (main power)as default.
BIOS default is 3 IN 5 OUT. The default set all of input and output pin
to “1”.
Digital I/O Software Programming
z
Digital Input/Output Assembler Sample Code
;Start set DIO program:
mov
dx,2Eh
mov al,87h ;Un-lock super I/O
out dx,al
out dx,al
mov
dx,2Eh
mov al,07h
out dx,al
mov dx,2Fh
mov al,08h
out dx,al
mov
dx,2Eh
mov al,30h
out dx,al
mov dx,2Fh
mov al,02h
out dx,al
;Programming DIO as in/out.
Mov
dx,2Eh
Mov al,0E0h
out dx,al
mov dx,2Fh
mov al,
N
;If N ’s value is 07h, DIO is programmed as input 3bits
out dx,al ; and output 5bits(3in/5out). ( Note1 )
Digital Input
;Read DIO digital input pins’ value.
mov
dx,2Eh
mov al,0E1h
out dx,al
mov dx,2Fh ; If N ’s value is 07h, Bit0 ~ Bit2 represent DIO0 ~ DIO2