TX2 UART3 is not readable and writeable

Hi guys:
I want to communicate with other device with Uart3 “/dev/ttyTHS3”( Pin H9 H10).
I just write the serial port with “write(int fd, const void *buf, size_t count)” method.
The returned value is always -1, and the errno always 0.

But i take “/dev/ttyTHS2” or “/dev/ttyTHS1” as the serial port, i never got this problem, write and read success.

I appreciate anyone help me very well.

hello xilaiwojia,

could you please check the configuration was correctly, you may search from the kernel message as below.

$ dmesg |grep ttyTHS

the connection speed should set as 115200/8N1, please also refer to Serial Console – NVIDIA Jetson TX2.