User`s manual

CT-XBT0x Mini-ITX Motherboard

3.10 General Purpose Input Output

GPI and GPO pins may be implemented as GPIO. GPI and GPO pins may be

implemented as SDIO.

Signal I/O Description

GPO[0:3] O

General purpose output pins. Upon a hardware

reset, these outputs should be low.

GPI[0:3] I

General purpose input pins. Pulled high

internally on the Module.

3.10.1 GPIO Configuration

Board Design

Pin# GPIO# Default Configuration

1 VCC3

2 GND

3 DIO_PH_OUT0 GPO0

4 DIO_PH_IN0 GPI0

5 DIO_PH_OUT1 GPO1

6 DIO_PH_IN1 GPI1

7 DIO_PH_OUT2 GPO2

8 DIO_PH_IN2 GPI2

9 DIO_PH_OUT3 GPO3

10 DIO_PH_IN3 GPI3

Notes

1. Output pin default setting is “HIGH”

The GPIO function is provided by a Fintek F81866 AD-I, and it can be

accessed through its GPIO index/data port. The index port is the base address

+0 and the data port is the base address +1. To access the GPIO register,

write index to the index port, and then read/write from/to data port. The

configuration on the CT- XBT0x is described as below.

Index Port 0xA00

Data Port 0xA01