How to cummunicate with FP from Mstudio via Instrument I/O Assistant

[jeppe]

 We recently purchased a FP-1001 (RS-485 interface) and a FP-A1-111 (16 ch. 16 bit current input) and Measurement Studio.

On the computer with Measurement Studio we have a NI USB-485/4 device attached connecting the FP modules.

I was hoping to use DAQmx with the USB-485 but I quickly learned that did not work - so I turned to NI-VISA to read/ write the serial communication.

NI-VISA in Mstudio v. 7.1 has a 'Instrument I/O Assistant' - with the I/O Assistant I can select the device (ASRL7::INSTR) on COM7 - but to 'Query and Parse'/ sending a receiving the FieldPoint Optomux commands is not a success.

For instance - I would like to read Channel 1 on the FP-A1-111 which has address 01. I am trying to use the extended command 'READ 16 bit Data' - !F

>01!F0001??

I am getting a TMO Error 15 - "Timeout expired before operation completed"

I assume I am not doing the querying in the right sequential order and a 'Start Monitoring' is required before I can query- but I am not sure how much the I/O Assistant is doing for my and I can't seem to find any documentation on FieldPoint and Optomux session sequences.

Clearly I am new to this and I am not even sure I am heading down the right road with VISA and Serial FP-1001 – or I am heading for trouble.

Any suggestions to the above or alternative solutions are very much appreciated.

Thanks in advance,

Jeppe

[Laura F.]

Hello Jeppe,

Have you seen the FP-1001 Programmer's Reference Manual?  I think this would be a great place to get started and should give a lot of help with using the Optomux commands.

Thanks,

Laura

[jeppe]

Thanks for the input.

In the meantime I've found out the easiest way to communicate with FP-1001 (Serial) and FP-A1-111 is via the OPC server. This server will handle the Optomux commands.

The OPC Client to the Server is the DataSocket.

Now - would I need 1 DataSocket for every 16 channels (every 1 OPC item) - or can 1 DataSocket handle multiple connections?

Tia,
Jeppe

[Laura F.]

Hello Jeppe,

For each item that you create in Measurement and Automation Explorer (MAX) you need 1 datasocket connection.  You can group multiple channels from one module together in one item, as you alluded to.

Thanks,

Laura