LabView TCP Read

[pjd7777]

Hi,

I am trying to read data from a personal weather station that is transmittng the data to a web site using a bridge.  I can see the data being transmitted with WireShark, so I know the bridge is working and that the data is there.  Also the data is getting to the web site.

I want to read this data, using LabView, as it is being sent to the web site.

I have tried the TCP Open Connection with the TCP Read function and also the TCP Listen.vi with the TCP Read function with no success.

I have attaced the two VIs and also a screen shot from WireShark.

One question I have is, How do I know what port to monitor?  It keeps changing in WireShark?

Any help is appreciated.

Perry

[tst · Accepted solution]

The TCP functions in LV are not sniffing functions. They are used for direct point-to-point connection.

If the web site supports getting the data back, then you can try contacting it and reading the data from it (probably use the HTTP or web service VIs, depending on the API the site provides).

Alternatively, you could try emulating the site in LV and having the unit send the data to you, but presumably the site address is hardcoded in the device. You could probably play around with it by faking a DNS server which will reroute it to your computer, but you would still need to know what the API for sending data to the site is.

A third option is to do the sniffing you want. LV doesn't have functions for this, but you can find some wrappers that people wrote for WinPCap, which might do what you want. I never used them, so I wouldn't know.

[pjd7777]

Thanks, I will give one of these a try.