I am having troubles with the UART 0 port of Auvidea J90 carrier board with Jetson TX-2. That port doesn’t react at all using write/read operations on it. Within the dev directory ttyTHS1, ttyTHS2 and ttyTHS3 are available. On UART 2 interface I attached another serial device and it works perfectly through the ttyTHS1. But UART 0 can’t be accessed with the current firmware version 1.5 (kernel and patches) for J90/J100/J106/J120/J130/J140 and JetPack 3.2 with L4T 28.1.
Within the Auvidea J90 documentation I found this:
On the J90-LC the UART 0 is directly connected to connector J14. On the
J90 UART 0 is tunnelled through the on-board micro controller (MCU) and then connected to J14. This allows
the MCU to monitor the UART 0 communication for watchdog applications.
Do I need to control the MCU functionality in order to access UART 0?
Any ideas for resolving that issue will be highly appreciated.