Using a TCP/IP Connection to REQUEST and RECEIVE data from a iDRX Signal Conditioner through a EIS-2B Server

[Dave@Ventec]

First let me say that I am new to labview, please bear with me.  I want to use Labview to querry a iDRX thermocouple signal conditioner using tcp/ip.  The signal conditioner is wired to a EIS-2B server.  The server is at 198.162.10.53 and port 2000.  The data request command is *10x01\r and the expected data to be returned is 01X01+00064.6 (or whatever the actual temperature is).  The conditioner and server are working and testing correctly using the iDRX supplied software.

My attached vi runs, creates no errors, but returns no data either.  I can find many examples of how to set up a listener, but I need to QUERRY and then RECEIVE the data.

Thanks in advance.

[MattP]

Hi Alyeska!  Welcome to the forums!

I took a quick look at the VI, and I have four quick suggestions for you that may give us some information about what is happening.

You may be experiencing an error that just isn't detected by the VI - normally we add an error handling VI at the end of program execution to report any errors that occurred.  Also, it's helpful to have a way to exit the while loop so that the program can finish executing if an error occurs.  Third, you may need to introduce a delay between the query and the read command to allow the server time to process and respond to the request.  Lastly, if you already know how long the return message will be, you should wire this length to the Bytes to Read input of the TCP Read VI so it knows to return the data once it receives that number of bytes.  I've attached a modified version of the VI incorporating these - give this a try, and let us know if you still see an error, and if so, what error.  Also, if you haven't taken a look at it already, there are excellent resources for learning LabVIEW at the LabVIEW Fundamentals page - it's a great way to introduce yourself to LabVIEW and get up to speed quickly.

[Dave@Ventec]

Matt,

Thanks for your help!  Your code did produce data and I am on my way.  My other problem was not having the TCP Write string constant in the "\" codes display mode.

Thanks again,

David

[MattP]

Alyeska,

Always glad to help!

[Garibay]

I am interested in this program, but I can not open it because I have an older version (LabView 7.1). Can you convert the program  an send it to my e-mail cecilia@mechatronics-d.com?

thank you

[Dennis_Knutson]

I can't save it as LabVIEW 7.1 so here's an image of the block diagram.

p.s. It's not a good idea to post your email to a public forum. Responses are all made to the forum anyway and all you will get is a lot of spam.

Message Edited by Dennis Knutson on 01-12-2008 12:43 PM

[shanky1023]

I have a signal conditioner iFPX-W.. its suppossed to give me Frequency output. i used the same .vi file from the prev post .. attaching it too.. modified a little for my case.
The problem  seems to be the same.The code runs but does not return a data value. Also i would like a continous graphical real time output of the measure frequecy as in when the Frequency changes it is displaye din the graph..

Can u please help me modify the code. the command *SRA\r seems to be right ... but i cant get any output.

[shanky1023]

http://www.omega.com/iseries/Pdf/M4051O.pdf

[Justin_P]

Hi Shanky,

I think that you should take a look at the code posted by Matt Pollock and note the original poster's comment "My other problem was not having the TCP Write string constant in the "\" codes display mode."

I have a feeling that you will need a wait between the write and read and your code looks to be in "Normal Display" mode.

To change your code to "'\' Code Display", right click on the "*SRA\r" string constant and select "'\' Code Display".

Please let me know if this helps.

[shanky1023]

Hi Justin...

I had figured that out.. now the code does give a data and its correct.. but i need a small modification and i cantfigure out how to get it cause i am new to labview..

The data is not continuous and keeps getting updated every 5 seconds or so..

is there a way i could get a continous data output in a Waveform chart ???? I know the TCP read command just gives a single valued output but could you suggest me how to get a waveform output in a continouw way.. i am attaching the Code... this works fine...