TRB255 was reading data from modbus rs485 and sending over http post.
After few days, it stopped sending the data.
While trying to investigate the reason, we found out that the tab RS485 in Modbus Serial Master was missing.
Rebooting the router from System - Reboot didn't solve the problem, so also Auto Reboot will not work.
Removing the power connector and plugging it back did solve the problem.
What is the reason of this missing RS485 tab and how to solve it?
The device is not easily accessible, so it need to be bulletproof.