Appendix C Digital I/O Interface
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Appendix C Digital I/O Interface
C.1 Introduction
The DIO connector on the AESQ67-967 Series is interfaced to GPIO ports on
the Super I/O chipset. The DIO has both 4-bit digital inputs and 4-bit digital
outputs. The digital inputs and digital outputs are generally control signals
that control the on/off circuit of external devices or TTL devices. Data can be
read or written to the selected address to enable the DIO functions.
NOTE:
For further information, please refer to the datasheet for the Super I/O
chipset.
The BIOS interrupt call
INT 15H
controls the digital I/O.
INT 15H:
AH
– 6FH
Sub-function:
AL
– 8
:Set the digital port as INPUT
AL
:Digital I/O input value
C.2 Assembly Language Sample 1
MOV
AX, 6F08H
;setting the digital port as input
INT
15H
;
AL low byte = value
AH
– 6FH
Sub-function:
AL
– 9
:Set the digital port as OUTPUT
BL
:Digital I/O input value
Table C-1: AH-6FH
