Simple Serial monitor communications

This activity introduces the Serial monitor and basic print commands to monitor program activity.

When you uploaded the blink program the computer sent information through the comm port to the Arduino's program memory. This uses the computer's USB port and the Ardunio's USB connection through the TX and RX pins of the Arduino. While the program was uploading you may have noticed the TX and RX LEDs flashing. The TX and RX pins are also connected to the Arduino's I/O pins 0 and 1. For this reason. it is important not to use pins 0 or 1 if you also need to use serial communication with the Arduino