I2C Configuration

Step 1: Enable the I2C port of your Raspberry Pi (If you have enabled it, skip this; if you do not know whether you have done that or not, please continue).

sudo raspi-config

3 Interfacing options

P5 I2C

, then ->

Step 2: Check whether the i2c modules are loaded and active.

lsmod | grep i2c

Then the following codes will appear (the number may be different).

i2c_dev                     6276    0
i2c_bcm2708                 4121    0

Step 3: Install i2c-tools.

sudo apt-get install i2c-tools

Step 4: Check the address of the I2C device.

i2cdetect -y 1      # For Raspberry Pi 2 and higher version

i2cdetect -y 0      # For Raspberry Pi 1

pi@raspberrypi ~ $ i2cdetect -y 1
    0  1  2  3   4  5  6  7  8  9   a  b  c  d  e  f
00:           -- -- -- -- -- -- -- -- -- -- -- -- --
10: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
20: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
30: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
40: -- -- -- -- -- -- -- -- 48 -- -- -- -- -- -- --
50: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
60: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
70: -- -- -- -- -- -- -- --

If there is an I2C device connected, the address of the device will be displayed.

Step 5:

For C language users: Install libi2c-dev.

sudo apt-get install libi2c-dev

For Python users: Install smbus for I2C.

sudo pip3 install smbus2