AXIOMTEK EP820 Series, User Manual

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EP820 All-In-One EPIC Board User’s Manual
Digital I/O
71
A p p e n d i x B
Digital I/O
Using the Digital Input Function
Start
↓
Un-Lock SuperI /O:
O 2E 87 ; Un-lock super I/O
O 2E 87 ; Un-lock super I/O
↓
SelectMultiplexed pin to GPIO Function:
O 2E 2A
O 2F FF
↓
Select Logic device:
O 2E 07
O 2F 07
↓
Activate Logic Device:
O 2E 30
O 2F 01
↓
Select GPI Function:
O 2E F0
O 2F F0 ; for 4IN / 4OUT
( When set to a '1', respective GPIO port is programmed as an input port.
When set to a '0', respective GPIO port is programmed as an output
port.)
↓
Read Data:
O 2E F1
I 2F
XX ( XX is input Data;
if no input source,the value is FF)