Then, using the function “write()”, some characters containing some letters signs are sent, and then, a byte of the actual data is sent. Then, using the function “beginTransmission(8)”, the address of the slave is entered and I2C communication is started for data transfer.In the main loop, the analog input is stored in the variable “value” and converted to the range of 0-255.

We start working with library using the “begin()” function.

The following points are worth mentioning regarding the code above:

We want to send the value of the potentiometer on the master side to the slave and receive a byte of the potentiometer data by the slave, display it on the Serial Monitor and control the brightness of the LED with it. onRequest(): This is defined as a function by the slave and is called when data is requested by the master.onReceive(): This is defined as a function by the slave and is called when data is received from the master.setClock(): This is used by the master to set the clock frequency.read(): The function for reading a byte of data from the I2C bus.available(): Both the master and the slave use this function to calculate the number of bytes received (by the “read()” function).write(): Both the master and the slave use this function to send data to the I2C bus.endTransmission(): The communication started by the previous function ends using this function.beginTransmission(): This function which is used by the master starts the communication with a special slave using its address.The number of bytes and also the slave address are specified in this function. requestFrom(): this function is used on the master side and can be used to request data transmission from the slave.begin(): Using this function, you can determine the Arduino board to be the master or the slave.

This library has a lot of useful functions, including: Working with the I2C communication protocol would be so easy using this library. To work with the I2C protocol, we use the “Wire” library, which is one of the Arduino IDE libraries.

How to use wire h library arduino