Data Sockets Problem

Hi,
I have written an applet with the following code that opens a simple socket. The problem is that I can only run one copy of the applet at once or I get an IOException can not create socket. Can any help me out
Thanks for any help
Joolz
//// Start Code ////
public tcpip(InetAddress ipa, int port)
Socket _given = null;
try
_given = new Socket(ipa.getHostAddress(),port);
catch(IOException e) {System.out.println("Error creating socket..");
return;
//// End Code ////

Hi,
Here is the error message, I don't have access to the server.
Error creating socket java.net.connectException Connection refused connect.
Thanks
Joolz

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Data socket problems with LVRT 8.2

I am in the process of migrating to LV 8.2 from LV7.1.1. My system has 18 RT targets which send data to a Host PC through data socket (DS). The Host PC runs LV on Windows XP Pro. With LV7.1.1 on both host and RT targets DS works perfectly. The RT targets update the host every 500 ms.
I've taken a three-step process in the migration. First tests were done with the host migrated to LV8.2 while keeping the RTs at LV7.1.1. Result: the system worked perfect. Then I changed one RT to 8.2 keeping the rest the rest at LV7.1.1. Result: DS timed out before all the data could be sent to Host. Finally, all RTs were migrated to LVRT 8.2. Result: Only about 5 out of the 18 RTs report to the Host before DS times out. However, if only one RT target is used, i.e., the other 17 RTs are diasbled, communication is very fast. Is there a special setting that I need to make? Btw, the roughly 5 RTs that report vary randomly from test to test, i.e., there is no bias towards any particular RTs.
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Ben,
I must say I am very surprised by Nadim's email. His point, which I must say I don't agree with, was made quite clear to me yesterday during a conference call between my team and the NI team comprising Chris, Nadim, and Avinash. So I don't know what purpose this morning's email is supposed to serve. Be that as it may, I think NI has gotten it wrong here. I do not think it should be one or the other. The discussion forum is a much wider forum comprised of people with varying experiences - not just NI employees. That is precisely why I posted my problem to the forum: to tap into the vast experiences of the discussants. But when I did not get any responses after I had posted answers to Nadim's questions, I decided to make a formal service request to NI, all perfectly legal. So I was really surprised when I was being blamed for tying up NI resources on one problem. I believe the resource allocation issue should be NI's to solve, not mine. I have no way of knowing that NI had formally assigned somebody to my problem. What if nobody from NI responds, am I allowed to make a service request to NI? My feeling is that NI's logic is flawed here, assuming Nadim's views are NI's views.
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Create OPC I/O server and front panel data socket problem

Hi all!
I installed the NI OPC server. When I try to create a new server I/O in a LabVIEW project I don't see the "OPC client" possibility.
Is something software missing?
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Dear vajasgeri1,
do you have LabVIEW DSC module installed? Without it you will not have the OPC client funtionality.
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Problem with data socket server

We have developed a program (from LabVIEW 6.1 running on Windows NT) consisting of a main executable and four other executables dedicated to collecting various i/o information. The four i/o executables convert raw data into process data and pass it on to the main executable using Data Sockets. The data is assembled as a cluster, then flattened into a string, which is published to a data socket variable. The data cluster contains a time stamp used by the main executable to verify i/o is being updated periodically (at least once a second). The main executable generates an alarm if the timestamp gets to be more than 5 to 15 seconds old, depending on the expected data. Typically, this alarm never happens, unless an i/o device is powered down o
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Thanks in advance for your help.
Brian Hajder
Despatch Industries
8860 207th Street West
Lakeville, MN 55044
Phone: 952.469.8111
Fax: 952.469.4513
[email protected]

Hello Matt,
Thank you for reading & responding. I should try to summarize this specific application in a little more detail.
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I wonder what you mean by "the datasocket
server resetting"? Is this documented anywhere?
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Problems with data socket connection

I have two computers on a network both running labview. I would like to
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Thanks for the Port number, I got it to work now.
I will summarise what was necessary to establish a connetion in case other people are interested:
If you need a bidirectional communication between computer A (IP:192.168.0.1)
and B (IP: 192.168.0.2) the following steps may be necessary:
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What is the purpose of open/close connection data socket?

Hello everyone,
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Attachments:
Test Event.vi ‏11 KB

Hi YehChia,
I was talking about something like that:
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Greetings,
I have an LV 8.6 HMI that performs Data Socket reads
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Attachments:
DS Related Error.PNG ‏10 KB

Hello,
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National Instruments
RIO Embedded Hardware PSE
CompactRIO Developers Guide

Data Socket

I am reposting this message and hope someone can help me....
I have been using Data Socket to pass information from a control computer
to two
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data. Has anyone else experienced this? Does this seem like a "network
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I got this answer from another question posted on the NI website. I don't know if it will help but it seems like this may be the same problem.
Jeff M. on 8/8/2001 answered:
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Data Socket Documentation

Could someone please help me find detail Data Socket documentation regarding allowed urls and Timouts.. For example what expressions are not allowed for making connections(.html)? And what is the maximum Timeout (seems to be limited to ~20secs)? -SS

Unfortunately, there isn't a single source that I would call the "definitive" data connection resource for LC Designer. I would suggest using information from the following resources at your disposal:
These forums. There are lots of examples here on data connections and some Adobe personnel along with many other very knowledgeable customers providing answers.
The
Working with Data Sources help topic in LC Designer Help.
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Data socket open?

I have one computer with a data socket that I write some waveforms to
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Jesse Wodin

Hello,
One way to do it would be to simply check for that error in your loop. If it occurs, you know the connection was lost, otherwise you're receiving data!
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Best,
JLS
Sixclear

Data Socket fails if built in DLL and called by Labview

I've placed a Data Socket Connection Open in a SubVi and tested this by running the VI. -> No Problems.
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Hello Carsten_S.....
my collegue, who found this behaviour made a little package to
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Message Edited by BLAQmx on 03-06-2008 01:12 PM
Mark
LabVIEW R&D

Why can't I read what I have written to the data socket server?

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Attachments:
readwriteDS.zip ‏17 KB

hi there
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Best regards
chris
CL(A)Dly bending G-Force with LabVIEW
famous last words: "oh my god, it is full of stars!"
Attachments:
set_flag_v2_LV7.1.vi ‏43 KB

Dynamically create Variant Data Socket items with multiple writers

I want to use variant or cluster items with data socket connection. I want to allow multiple writers.
So far I can create these items dynamically but not set them to allow multiple writers.
For numeric, string, and Boolean items I can set these properties by predefining them in the data socket server manager. I could not predefine a variant or cluster in the manager.
I realize I can flatten to string the item needed but would prefer to do this in the cluster or variant formats.
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unclebump wrote:
Could you accomplish this using a functional global architecture??
An interesting concept which might work and did just open up a new host of possibilities!
When I get the time I might give this a try. I just did a quick test in another program.
Through VI server I opened a reference to a remote machine. I then created strictly typed reference to a âfunctional global viâ that I knew would be in memory. It reads the functional global just fine!
Thanks for the suggestion.
Here is the work around I used for the data socket program.
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I needed to know on the server side when a new value was written to the message cluster, which consisted of a string and a variant. Checking the string portion of the cluster let me know what command to send the device being controlled on the server machine. The variant is used to hold the various parameters that accompanied the command. Since the same command type could be sent several times I needed to reset the string control after the server read the command. This required writing to the data socket from the client & server machine (multiple writers). Also since the client could be any PC in the subnet I needed to allow all these machines to have write access.
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Data socket. how to implement this?

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Hi Mike,
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Configuring a DataSocket Server
http://zone.ni.com/devzone/cda/tut/p/id/3123
Can Multiple DataSocket Writers Connect to the Same Item?
http://digital.ni.com/public.nsf/websearch/A8AC9A751404BAB18625672400630A3D?OpenDocument
Nick Keel
Applications Engineering
National Instruments
Nick Keel
Product Manager - NI VeriStand and Model Interface Toolkit
National Instruments

Data Sockets Problem

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