Applies To:
  • CitectSCADA 1.20 2.00 2.01 3.x 4.x 5.x

There are a number of different Profibus protocols and they don't communicate between each other. This article is a short explanation of which Citect currently supports and which Driver to use. 

The following can all run on the same physical hardware, the PC card and the networking cables are the same. The Softing PROFI-IF-PCAT card and the Siemens CP5412 card are identical, either can be used for the Citect SINEC and PROFI Drivers. Low level software drivers may be different. Devices on a Profibus network using different Profibus protocols cannot communicate with each other. Following is a brief summary of the different Profibus protocols.

Profibus FMS (Fieldbus Message Specification) (Siemens L2-FMS protocol)

  • interface at Layer 7
  • supported by Citect's PROFI, PROFIB, PROFIBNT, and PROFIBD drivers.

Profibus FDL(Fieldbus Data Link)

  • layer 2 interface (PLC code provides additional layers 3-7. PLC Code only available for S5 Series PLCs at present)
  • peer to peer PLC communications
  • Supported by Citect's SINECFDL (CP5412) and SFDL (CP5412A2) cards.

Profibus DP(Distributed Peripheral) (Siemens L2-DP protocol)

  • used for small distributed IO devices.
  • Supported using Citect's OPC driver at present - Softing OPC server is an OPC server that supports Profibus-DP. Please read KB Q2678.

S7 Protocol

  • Used by Siemens S7 range of processors
  • Supported using Citect's SSEVEN driver on Citect V5+


  • a Siemens layer 7 interface
  • supported by Citect's SINEC Driver (CP5412 card and Citect V3 only)