UARTsΒΆ

The Duckbill comes with two UARTs on the pin headers. The Debug UART (part of connector 4) is usually used as system console, while the second UART (part of connector 3) is used as application UART. Please note, that the Debug UART has 3.3 V level, so do not connect it directly to your PCs serial port. We recommend to use an USB to UART TTL level adapter; there are plenty products available.

Attribute Debug UART Application UART
Function System console Customer defined
Linux Device /dev/ttyAMA0 /dev/ttyAPP0
Baudrate 115200 115200
Data bits 8 8
Parity None None
Stop bits 1 1
Flow control None None

The settings listed above are default values. For the Debug UART, we do not recommend to change the settings.

The application UART uses only Rx and Tx lines by default, but not RTS/CTS. If your application required hardware flow control, you have to modify the Device Tree binary to use the correct pin muxing on the additional required pins. In this case, you loose this/these pin(s) for other functionality.