deterministic connection PXI LV RT and Siemens S7-400

[nicophenix]

I'm looking for the best solution to perform a deterministic link between a PXI running LV Real Time and a PLC Siemens S7-400.
In this application the PXI acquire all analog data and the Siemens PLC needs the analog data from the PXI to make decision about alarms,..,. But we need a very reliable and deterministic link between both systems.
there is two different solution :
the first one : the profibus link with a applicom card, but I don't know if this card is supported by LV RT.
and the second one : a industrial Ethernet link, I suppose this link don't need a special card in the PXI chassis ... I suppose the industrial Ethernet link from the Siemens PLC is fully compatible with the standard Ethernet link form th
e PXI.

is it possible to use another link ?
which link is the best link to have a deterministic and quickly communication between these two systems ?

[JorisV]

Hi Nico,

1. There is no LV RT support for an Applicom card to connect to a Siemens PLC. You will have to write your own driver with VISA calls. No determinism guarranteed.

2.Datasocket utilizes Microsoft Windows components for its OPC functionality. This means it cannot be used on the Real-Time operating system and other traditional LabVIEW platforms like Macintosh, Solaris, and Linux. There are, however, other ways to transfer information between your LabVIEW Real-Time embedded application and an OPC server on a host PC. Since LabVIEW Real-Time cannot communicate with directly with an OPC server, an intermediary application is needed. This application can be a LabVIEW VI that receives data from the RT engine and uses DataSocket to write to the OPC server. To tran
smit the data from the RT engine to the host VI, you could utilize DataSocket, TCP/IP, or UDP on both the host PC and RT engine.

3. Ethernet is not deterministic. Maybe a deterministic Ethernet protocol written on a FPGA card.

4. The solution can be CAN which is supported under RT.

5. Or using direct digital communication on bit level.

Regards.

Joris Vanderschrick
Team Leader Application Engineering
NI Belgium