Communications Test Rig for Common Protocols


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I am looking to set up a demonstration/Test rig where common protocols i.e. Modbus, Profibus, Hart, etc. could be set up to communicate with devices such as chart recorders. Is there anything on market? What would be a good entry cost to build and apart from Wireshark? Any suggestions on suitable protocol tools?
What tasks are you doing that you need a protocol analyzer for?

I've connected devices to Modbus enabled recorders (both as master/clients and slave/server), but have never needed Wireshark to analyze the serial or TCP traffic to get them working, but I could have been lucky.

The recorders I've encountered have not had HART enabled inputs, so I've used a HART-to-Modbus converter.

HART point-to-point for configuration has always worked with enough resistance in the loop, except once when I found a power supply that would eat all the HART FSK data. Changing the power supply got HART running.

It is my impression that the commercial HART Multiplexors use Modbus as the protocol to get data out of the gateway.

HART Multidrop needs a host program to poll the individually addressed devices on the network.

This link shows the value of an oscilloscope for finding something like a 'longer-than 3.5 intercharacter time-out' timing issue:
Consider a DCS with interface cards for the protocols you want to work with.

For example You can start with interfaces for Fieldbus, 4-20 mA/HART input, and 4-20 mA/HART output. Then you can add cards for Modbus, Profibus, ASI, and DeviceNet etc. as needed.

A chart recorder will not allow you to fully explore the capabilities of these protocols