IEI Technology PCIE-9452, User Manual

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PCIE-9452 PICMG 1.3 CPU Card
Page 224
B.1 DIO Interface Introduction
The DIO connector on the PCIE-9452 is interfaced to GIO ports on the iTE 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 iTE Super
I/O chipset.
B.2 DIO Connector Pinouts
The following table describes how the DIO connector pins are connected to the Super I/O
GPIO port 1.
PIN NO. DESCRIPTION PIN NO. DESCRIPTION
1 GND 2 VCC
3 Output 3 4 Output 2
5 Output 1 6 Output 0
7 Input 3 8 Input 2
9 Input 1 10 Input 0
B.3 Assembly Language Samples
B.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