4.1. I2C serial protocol and data messages
In the I2C communication the main interface is the master and the other interfaces of the hardware platform are the slaves. The I2C data transfer is initiated by the master and other peripheral equipments are questioned with their 7-bit address. The synchronization of the devices is assured by the clock signal (SCL) generated by the master. The standard master-slave protocol contains the following information: start bit, 7-bit address of the slave, read/write bit (which defines the slave transmitter/receiver mode), acknowledge signal, data message (package of bytes), and stop bit [18].