ProSoft MVI56-DFCM ControlLogix DF1 Master/Slave Communication Module

Configured for multi-point serial protocol conversion in Rockwell Automation ControlLogix architectures, the ProSoft MVI56-DFCM (MVI56-DFCM Network Interface Module) provides direct physical/electrical execution. The module enables bi-directional data exchange between ControlLogix backplanes and legacy DF1-compliant field devices over dedicated serial links. Operating as an input/output interface, it handles protocol formatting internally to offload serial communication overhead from the primary system controller.

Hardware Specifications

Backplane Bus Latency and Deterministic Network Isolation

The MVI56-DFCM acts as an independent backplane module, transferring serial field data into its internal 5000-register database before executing deterministic backplane transfers to the ControlLogix processor. By isolating the serial polling routine from the controller execution cycle, the module prevents asynchronous serial delays from impacting main controller scan times. High-speed backplane bus communication velocity allows rapid memory map updates via block transfers, while software-configurable port baud rates (up to 115.2 kbps) maintain predictable throughput across complex DF1 Master/Slave network topologies.

Frequently Asked Questions

Q: What is the backplane current draw required by the MVI56-DFCM module during operation?

A: The module draws 800 mA at 5.1 VDC and 3 mA at 24 VDC from the ControlLogix backplane power supply.

Q: Can the serial ports on the MVI56-DFCM be independently set to different electrical standards?

A: Yes, each of the two RJ45 serial ports is individually software-configurable to operate under RS-232, RS-422, or RS-485 physical layer specifications.

Q: Is ladder logic required to manage the DF1 serial communication protocol engine?

A: No, the module handles full-duplex and half-duplex DF1 protocol parsing internally via its command list database, requiring only basic I/O block transfers in the controller logic.

Field Installation Guidelines

1. Power off the target ControlLogix chassis before inserting or removing the MVI56-DFCM module to prevent backplane edge-connector damage.
2. Align the module with the chassis slot guides and slide it firmly into place until the top and bottom retention levers snap securely.
3. Utilize shielded twisted-pair cables for all RS-422 and RS-485 serial runs to minimize electromagnetic interference (EMI).
4. Ensure single-point grounding of the cable shield at the panel earth bar. Do not connect the shield at both ends to avoid ground loop currents.
5. Verify signal line termination resistors (120 ohm) are applied at the physical end nodes of RS-485 network segments.