Introduction - IEI Technology PM-PV-N4551/D5251 User Manual

E.1 Introduction
The DIO connector on the PM-PV-N4551/D5251 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
AL
Page 96
PM-PV-N4551/D5251 User Manual
:Set the digital port as INPUT
:Digital I/O input value