RS485 to external Modbus RTU board
I have Patron L207 and I'm trying to establish communication with following external Modbus RTU relay board
I tried this:
mbpoll /dev/extcomm/0/0 -m rtu -a 1 -b 9600 -c 8 -P none
But I get
Read output (holding) register failed: Connection timed out
Any hints on wwhat I am doing wrong? I have no experience with RS485 so I am totally stuck.