3.1.1.1 Overview

The on-board debugger implements a composite USB device that includes a standard Communications Device Class (CDC) interface, which appears on the host as a Virtual COM port. The CDC can be used to stream arbitrary data in both directions between the host and the target: All characters sent from the host will be sent through a UART on the CDC TX pin, and UART characters sent into the CDC RX pin will be sent back to the host through the Virtual COM port.

On Windows machines, the CDC will enumerate as Curiosity Virtual COM Port and appear in the Ports section of the Windows Device Manager. The COM port number can also be found there.

On Linux machines, the CDC will enumerate and appear as /dev/ttyACM#.

On MAC machines, the CDC will enumerate and appear as /dev/tty.usbmodem#. Depending on which terminal program is used, it will appear in the available list of modems as usbmodem#.

Info: On older Windows systems, a USB driver is required for CDC. This driver is included in MPLAB X IDE and Atmel Studio installations.