Modbus-RTU and Modbus-TCP on a HIPservice
The Modbus protocol enables data transmission between devices using a serial interface.
Modbus-TCP applies to:
Beginning with Firmware 2.1.6, we have added Modbus support making it possible to communicate over Internet or Intranet.
- HIPswitch-100s (RS-232)
- HIPswitch-150 (RS-232)
- HIPswitch-250e/g/d (RS-232 & RS-485)
- HIPswitch-300 (RS-232)
Modbus-RTU
The Modbus protocol is essentially a technique of enabling data transmission between devices using a serial interface. Our serial-enabled HIPswitches have been able to encapsulate Modbus-RTU (Remote Terminal Unit) over a serial line since since firmware 1.x.
With Firmware 2.1.6, we have enhanced our Serial over IP (SoIP) feature with Modbus-TCP (Transmission Control Protocol) support making it possible to communicate over Internet or Intranet.
After configuring Modbus via the HIPswitch SoIP settings in Conductor, the HIPswitch will accept Modbus-TCP commands from servers, issue the commands to serially-connected Modbus RTU device(s), and return the responses via Modbus TCP back to the server. This provides optimal efficiency for Modbus traffic in terms of throughput, latency, and number of messages as compared to transparent Serial over IP.
Modbus-TCP
Modbus-TCP is a frame-aware Modbus-RTU encapsulation that is compatible with modern Modbus/SCADA systems. Unlike SoIP, Modbus-TCP processes each Modbus frame as a separate packet, and transfers the burden of error correction to the TCP protocol.