Edge module and communication methods

An edge module configured to be connected between a management system and a device of an industrial system, the edge module comprising:

• an upstream serial port;
• a downstream serial port;
• a microcontroller comprising a memory storing program instructions and a processor to carry out the program instructions to:
• receive a first Modbus packet comprising a multi-register write command to a first contiguous array of Modbus registers, designated as a command buffer, sent across a communication link from the management system to the upstream serial port,
• translate the multi-register write command by mapping Modbus registers of the device that are associated with the multi-register write command;
• and
• generate and send a second Modbus packet comprising a command to the mapped Modbus registers of the device via the downstream serial port.

A method for an edge module to override a host device in an industrial control system, the method comprising:

• identifying, by the edge module, a type of the host device by probing the host device via a downstream port of the edge module to determine device information;
• mapping, by the edge module, resources of the host device, wherein the mapping includes determining register addresses of each resource;
• conditioning, by the edge module, the host device to be passive by disabling automatic control modes;
• and
• overriding, by the edge module, executive control of the host device by directly accessing and manipulating the resources of the host device in response to action commands from a management system.