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
5 Interfacing options
P5 I2C
<Yes>
<Yes>
<Ok>
<Finish>
<Yes> (If you do not see this page, continue to the next step)
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’s an I2C device connected, the results will be similar as shown above – since the address of the device is 0x48, 48 is printed.
Step 5:
For C language users: Install libi2c-dev.
sudo apt-get install libi2c-dev
For Python users: Install smbus for I2C.
sudo apt-get install python-smbus