I am testing an Android application loaded on a Nitrogen 6X board (uses i.MX6 quad processor) running Android 7.1 that communicates with another board via Serial Port. The first request I try to send after the port object has been created instantly times out. I have tried all the available port paths on the board (/dev/ttymxc0, /dev/ttymxc1, /dev/ttymxc2), but all timeout. I also tried manually sending data to the port via adb by echoing data to the port in one terminal and viewing the contents of the same port in another, but did not see the data go through:
Has anyone seen anything like this? If so, are there any solutions to this problem?