Trucrux Inc

Testing UART

There are total 4 UART.

UART1 -> ttymxc0 -> Used for USB debugging

UART2 -> ttymxc1 -> Free

UART3 -> ttymxc2 -> Free

UART4 -> ttymxc3 -> Used for Bluetooth  communication

Below is and example to test UART2

Testing UART #

Make a LOOPBACK by shorting Tx and Rx for UART2. Refer Carrier Board Datasheet for pinouts.

Login into device

Setting UART2 #
root@imx8mq-trux-q01:~# stty -F /dev/ttymxc1 -echo -onlcr 115200
root@imx8mq-trux-q01:~# cat /dev/ttymxc1 &
Transmit data #

To transmit data simply print a string over UART2.

root@imx8mq-trux-q01:~# echo hello > /dev/ttymxc1
Receive data #

To receive data, use minicom. Open minicom for ttymxc2 and check if the transmitted data prints on minicom terminal.

To open minicom

root@imx8mq-trux-q01:~# minicom -s

now for setting configrations select “Serial port setup”. Now set the tty-port by pressing “A” and set it  to /dev/ttymxc1. Then turn off the Hardware flow control and turn on the Software flow control by pressing “F” and “G”. Now exit the setup and check if the transmitted string is received.