Hi

I'm trying to transfer data between S7-400 and S7-300 via profibus as a multiple master, I know it's possible in SIMATIC with DP/DP coupler, But in TIA Portal v14sp1 It's working with PUT & GET function blocks without DP Coupler,I didn't see this possibility anywhere even in TIA help.

How It is working without DP coupler?

Hello yaray;

You can use PUT/GET functions between the S7-400 and S7-300 over Profibus, if you program them in the S7-400 CPU. The S7-300 integrated DP interface can only act as a server for S7 Communicatioons; to act as a client it requires a CP 342-5 in the rack.

This is explained in the following documents:

Which types of connection/protocols do the S7-300/400 CPUs and the CPs support by default?

https://support.industry.siemens.com/cs/ww/en/view/24352751

“S7 300: Client functionality only via CP342-5 from FW V5.2»

CPU-CPU Coimmunication with S7 Controllers.

https://support.industry.siemens.com/cs/de/en/view/78028908

The screenshots below are extracted from this last document (known as "The Kompendium").

Dear Dchartier

Thanks for your time, I appreciate that was exatly what i need.

In this case can't We use two S7-300  in S7 connection as a multiple master without CP 342-5?

Is this rule same as Simatic Step 7 v5.5 or there are differences ?