If any character is received from a remote serial terminal. This example sends a string on the serial port each 1 second at 115200,N,8,1 and checks Install the Python serial library: sudo apt-get update This port is visible in Linux as /dev/ttyUSB3 device. The signals are available on screw terminals as visible below and are at 3.3 volt level. A serial port interface at 3.3 volt is available on the CM3-Home to connect external microcontrollers like Arduino or ESP8266.
