I can't get a signal out of the arduino OPTA RS485 ports. I have a 24MHz8ch analyzer from saleae hooked up to the RS485 at the top of the opta.
when i trigger the signal with the senor i can't get a read on the analyzer.
i have used the AlModbusRTU and sysMbMRtu_FC06 library.
I think the problem might be the chn or pollingTime input but i can't find any documentation about this library.
currently struggling to set up modbus communication also, set chn to 0 and you should be able to get data out of the rs485 connection.
I am also having a problem with the arduinoModbus library on the finder opta (ModbusRtuClient). I connected the RS485 output to a RS485 to usb adapter into my notebook running hercules terminal emulator and the packet I receive when the opta polls is missing the last byte. (ID,0x03,StartH,StartL,QtyH,QtyL,CRCL and that's it... ).
Usually the problem is that the software immediately shuts the RS485 transmit enable line when the last byte is buffered and not finished transmitting (you usually have to monitor the last byte status for transmit complete, or wait for 1 byte frame time at baudrate before closing the line). I am unfortunately a noob at arduino environment and can't for the life of me get into the guts of the code so I can fix the problem myself.
The debug flag is also hidden so deep in the library with no function to enable it.