Modbus Master/Slave Tutorial for Diagnostics on MVI56E-MCM, MVI56E-MCMXT

The MVI56E Modbus Master/Slave Enhanced Communication Modules (MVI56E-MCM, MVI56E-MCMXT) allow Rockwell Automation ControlLogix processors to easily interface with devices using the Modbus RTU/ASCII serial communication protocol.

The MVI56E-MCM and MVI56E-MCMXT act as input/output modules on the ControlLogix backplane, making Modbus data appear as I/O data to the processor. Data transfer to and from the processor is asynchronous from the communications on the Modbus network. Two independently-configurable serial ports can operate on the same or different Modbus networks. Each port can be configured as a Modbus Master or Slave, sharing the same user-controlled 5000-word database.

The two modules are functionally the same. The MVI56E-MCM is designed for standard process applications. The MVI56E-MCMXT is designed for the Logix-XT control platform, allowing it to operate in extreme environments, at higher operating temperatures, with a conformal coating to protect it from harsh or caustic condition.

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