nRF52 PDK virtual COM port

The on-board Interface MCU features a Virtual COM port via UART.

The virtual COM port has the following features:

Flexible baudrate setting up to 1 Mbps.
Dynamic Hardware Flow Control (HWFC) handling.
Tri-stated UART lines when no terminal is connected.

Relationship of UART connections on nRF52832 and Interface MCU shows an overview of the UART connections on nRF52832 and the interface MCU.

Table 1. Relationship of UART connections on nRF52832 and Interface MCU
Default GPIO nRF52832	UART nRF52832	Interface MCU UART
P0.05	RTS	CTS
P0.06	TXD	RXD
P0.07	CTS	RTS
P0.08	RXD	TXD

The UART signals are routed directly to the Interface MCU. The UART pins connected to the Interface MCU are tri-stated when no terminal is connected to the Virtual COM port on the computer.

Important: The terminal used must send a DTR signal in order to configure the UART Interface MCU pins.

The P0.05 (RTS) and P0.07 (CTS) can be used freely when HWFC is disabled on the nRF52832.