Virtual COM Port

The EDBG features a CDC class USB interface that implements a Virtual COM Port. A UART connected to a target device is used to enable easy communication between a computer and the target.

The following configuration options are implemented

Baud Rate: Flexible and accurate settings up to 2Mbps
Parity: None, Even, Odd, Mark, Space
Stop Bits: 1 bit, 1.5 bits, 2 bits

The configuration options must be specified in the terminal application, which will propagate the configuration to the EDBG Virtual COM Port on connection. The target MCU UART must be configured to match the Virtual COM Port.

Note that the UART pins of the EDBG are tri-stated when no terminal program is connected to the Virtual COM Port on the computer. This mechanism relies on the terminal program sending a DTR signal.

The Virtual COM Port is supported by the terminal extension in Atmel Studio. Most other terminal applications will work as well.