SNAP Profibus Module

I have a question about the Profibus module. We have a customer who would like our system to communicate with a Siemens S7 300 PLC. They want to send us a setpoint and want us to send back data. I believe we can use Ethernet (TCP/IP) or possibly Profibus with the PROFI module. I’m sure the S7 will be the network master. Can the PROFI module operate as a slave? I plan on using an R2 controller.


We have master and slave examples for Profibus DP.
What other protocols does your system support.
The R2 supports Ethernet/IP, Modbus/TCP.
We have integration kits for DNP3, BACnet and Modbus/RTU or ASCII

I was looking back over the spec and it does specifically mention Ethernet. Anyway, I’m thinking either Ethernet TCP/IP or Modbus TCP.

I’d like the information to be available to the R2 and the S7 via the scratchpad. Can you access scratchpad information via Modbus TCP? I’ve been able to read digital and analog I/O via Modbus without any special software. That would be the easiest solution. I would assign a scratchpad register for incoming data and another for outgoing. Then I would just read and write to those registers without dealing with the communications details.


Hi Joey,

Yes, you can access any mem map address you like via modbus. Check out this post called: “[U][B]Modbus in the Middle[/B][/U]” for details and screen shots.