Name Version Release Date Size MD5
Modbus_Protocol.pdf Jul 25 2018 123.4 KB 9faa9832028e4df6bd44ec2f07a109f7

The JNIOR has a built-in MODBUS server. The application is loaded by default but not enabled. You must use the DCP to enable the MODBUS server application.

The MODBUS server that is built-in implements MODBUS TCP. MODBUS is a request / response protocol and is not as efficient as other protocols. That being said, MODBUS is widely used.

Since the JNIOR is security conscious, we have a login option built-in for applications where a custom function command can be implemented and sent. The Login is set to true by default. If a login cannot be sent, set the ModbusServer/Login registry key to false and reboot the JNIOR.

Modbus login registry key for Modbus application

INTEG can write custom applications to communicate with other MODBUS devices across any of the MODBUS protocols. MODBUS RTU over RS-485 can only be used on the JNIOR 410. The JNIOR 410 is the only model with RS-485 capabilities.

The MODBUS Server application is part of the All-In-One update. Here is the documentation for the MODBUS server and MODBUS TCP protocol implemented by the JNIOR..