modem IP

[alysko]

  Hello,

I need to acquire data from a number of remote Fieldpoint-based stations (clients). I will have a server running Windows. I intend to use a GSM/GPRS modem to establish the links. I can do everything "manually" (dial a number, establish connection, send/receive commands and data) but ... I would like to try to use the real power of LabVIEW (shared variables or DataSocket). How do I go about it?

I know that the modem (made by wavecom) have a built-in TCP/IP stack allowing me to get an equivalent of TCP Open/Read/Write etc. through the modem's serial port. However, how do I link all these together, so I could access the data from the remote stations with minimal programming?

Sincerely,

Albert Lysko

[Ankita]

Hi,

I believe the easiest way to communicate with the FP clients and Windows server would be by using Shared variables. If you have the FP module connected to the ethernet then you would not even need to use the modem.

Using the shared variable engine

Regards,

Ankita

[alysko]

Thanks for the response.

No, that's not what I want. I think what I want is a kind of TCP/IP over serial, which would bridge TCP/IP on the PC side with TCP/IP on the side of GPRS provider:

GPRS provider  ---+---  modem  (mobile equipment --+-- mobile terminal) ---+---  PC ( DTE --+-- VISA ---+--- end software)

[JasonSmith]

Unfortunately you will not be able to utilize Datasocket or Shared variables through this configuration, as they are only going to work through the FieldPoint controllers built-in ethernet port.  Although your GPRS modem has a built-in TCP/IP stack, the FieldPoint controller is not aware of this, and will see it as any other serial device. 

In order to communicate over TCP/IP you would need to send all of the proper commands to your GPRS modem through the serial port, using the Visa Open/Read/Write commands.  You have said that you already can successfully communicate "manually" with your controllers, this may be easier than utilizing the TCP/IP stack which is built in to your modem.

Jason S.
Applications Engineer
National Instruments

[Mackemann]

Hi Jason,

    I'm looking info about reading some data from a electronic module sent via GPRS. I've heard I can use a modem to read this data, is this possible? How can I control the model with LabVIEW? Do you have some examples or ideas? Does it have to be a special GPRS modem? I hope you can answer these questions. Thanks in advance,

Mackeman

[JasonSmith]

I am by no means an expert on GPRS, but this is my understanding:

The GPRS modem will install on your remote device, which will need to issue commands to initiate TCP/IP communications back to your server.  Your GPRS provider provides the internet connection, and you will need to run a service on your server that the GPRS modem can connect to.

This server in LabVIEW would be something similar to the TCP examples which ship with LabVIEW.  As far as communicating with the GPRS modem from your remote device, you would need to consult the documentation of your GPRS modem.  If the remote end is utilizing LabVIEW, you would need either a driver for the GPRS modem to make it appear as a TCP/IP connection in Windows, or the command set to use to control it through a serial port.

Jason S.
Applications Engineer
National Instruments

[Mackemann]

Thank you very much Jason!