S2C is a communications protocol than enabled serial communication through GPIO pins 3 and 5 known as the SDA and SDL pins. Some setup is required to enabled this communication.

First step is to install i2c tools, this makes detecting device addresses much easier. This can be accomplished by running the following command.

sudo apt-get install -y i2c-tools

Next you will need to make sure I2C is enabled on the raspberry. To do this, run the following command:

sudo raspi-config

You will presented with a menu screen. Select 5. Interfacing Options, and then P5, I2C. Enable this interface, exit and save configuration.