Arduino Bluetooth Wiring Diagram on Mega Boards
Arduino Mega has 4 serial communications Rx Tx. In designing Arduino Bluetooth using Mega board, we can use the four Rx Tx serial communication ports freely, but we recommend to use serial 1, 2 and 3 serial communications ports. Because for serial communication port 0 used by Arduino Mega to communicate with computer upon uploading the program from Arduino IDE software.
Wiring Arduino Bluetooth diagram on Mega board, in this experiment we use serial communication port 3. Wiring Arduino Bluetooth diagram as shown below.