Now many M2M applications require the Modbus feature. Some M2M Routers can support Modbus; but how to config this Modbus? Here we can check the E-Lins router as an example.

Config Modbus on router Web GUI; open page Services-> Modbus.

Note: if we want to access the Modbus server from WAN or cell port, then it requires config the firewall to open the TCP port.

1.     Connect terminal blocks pin TX, RX, and GND to DB9, then connect to PC serial port.

2.     Open Modbus Slave on PC which connects to router terminal blocks.

3.     Click connection then config it like this:

Config it as Serial Port, RTU. Baud rate, Data Bits, Parity, and Stop Bit shall be the same as the configuration of the Modbus page on the router.

4.     After all setup is done, click “OK”.

5.     PC connects to the router via ethernet cable, then opens the tool Modbus Poll.

6.     Click the connection, then config it like this:

7.     192.168.8.1 is the router LAN IP in this case. If you want to access it via cell interface, then it shall be a cell IP address. The Port is the same value as the TCP port at the router Modbus configure page.

8.     After all setup is down, then click “OK”.

9.     Config Modbus Slave, double click address 0 then config it as auto-increment.

10. Check the value on Modbus Poll.

11. Double click Grid at Modbus Poll, and set the single Register value as 5.

12. Check it at Modbus slave, the same register value changed accordingly.

If you have further issues or questions, just freely contact with E-Lins Tech Team.