IEI Integration IMB-G41A - Manual (Page 142)

IMB-G41A Micro-ATX Motherboard
Page 130
C.1 Introduction
The DIO connector on the IMB-G41A 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.
C.2 DIO Connector Pinouts
Refer to the connectors section for pinouts.
C.3 Assembly Language Samples
C.3.1 Enable the DIO Input Function
The BIOS interrupt call INT 15H controls the digital I/O. An assembly program to enable
digital I/O input functions is listed below.
MOV AX, 6F08H Sets the digital port as input
INT 15H Initiates the INT 15H BIOS call
C.3.2 Enable the DIO Output Function
The BIOS interrupt call INT 15H controls the digital I/O. An assembly program to enable
digital I/O output functions is listed below.
MOV AX, 6F09H Sets the digital port as output
MOV BL, 09H
INT 15H Initiates the INT 15H BIOS call