FWA-2112 User Manual
8
1.3.2.1
Locate i2c Bus of IO Expander
How to locate i2c bus of IO expander is shown as below:
1.
Make sure i2c driver is loaded.
Use lsmod to check if driver is already loaded:
2.
Install i2c-tools package.
I2c tools could be installed from Ubuntu’s repository simply:
Or built from source package in website. please check README in package.
https://www.kernel.org/pub/software/utils/i2c-tools/
3.
Scan smbus in system by i2cdetect.
Here shows system smbus adapter is located at bus 8. Please note the bus number
could be different due to different hardware configuration, kernel version and driver of
other devices.
4.
Confirm smbus switch.
Scan the devices on smbus which is got in step 3, and see smbus switch appears at
0x71.
5.
Open smbus switch, 0x71, channel 8 for I/O expender.
# modprobe i2c_i801
# sudo lsmod | grep i2c
# sudo apt-get install i2c-tools
# sudo i2cdetect -l
# i2cdetect -l
i2c-0 i2c igb BB I2C adapter
i2c-1 i2c igb BB I2C adapter
i2c-2 i2c igb BB I2C adapter
i2c-3 i2c igb BB I2C adapter
i2c-4 i2c igb BB I2C adapter
i2c-5 i2c igb BB I2C adapter
i2c-6 i2c igb BB I2C adapter
i2c-7 i2c igb BB I2C adapter
i2c-8 smbus SMBus I801 adapter at e000 SMBus adapter
# i2cdetect -y 8
0 1 2 3 4 5 6 7 8 9 a b c d e f
00: -- -- -- -- -- 08 -- -- -- -- -- -- --
10: -- -- -- -- -- -- -- -- 18 -- -- -- -- -- -- --
20: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
30: 30 31 -- -- 34 35 36 -- -- -- -- -- -- -- -- --
40: -- -- -- -- 44 -- -- -- -- -- -- -- -- -- -- --
50: 50 -- -- -- -- -- 56 -- 58 -- -- -- -- -- -- --
60: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
70: -- 71 -- -- -- -- -- --
# i2cset -y 8 0x71 0x80
