Multiple write operation on datasocket possible?

I am using datasocket to communicate between to applications, the first application writes a command on the datasocket url and the second application reads this command and after interpreting it writes some parameters on the same url, but i am having problems with this type of arcitecture. some times the commands are not read by the second application. I also wanted to know if after writing the command if i do a read operation on the same url then will the command be lost for the second application?

Hi Philip
Thanx a lot for your answer. i have created 2 diffrent items now and read write takes place on seperate items. But now i have another problem, i.e if i convert the vi's to application, the server is not able to read what is written on the url. i have attached the vi's along wid this mail, kindly change the url accordingly, before converting them to application and running.
thanx for your answer
Arun
type of command can be changed from 0 to 2
for 0 server answers as OK
for 1 server currently does not reply
for 2 server answers as OK
but if it is converted to application server does not the receive the commands.
Attachments:
datasokclient.zip ‏40 KB

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Multiple writes possible in DS in labview but not in CVI?

Hi
Am using Datasocket to communicate between to VI's, In one of the VI's am opening a new dataitem in "readwrite" mode and doing both read and write operation, and in the other VI am just writing on the dataitem by supplying the URL to the write function, surprisingly this is possible even though i havent created the dataitem from DS manager and have not selected the option of "allow multiple writes".
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Hello,
The following Knowledge Base describes two possible soltions for this issue.
Why Does My DataSocket Connection in LabVIEW Fail with "Error: Can't connect to data item, another w...
The second solution is what you have already described with checking the box to Allow Multiple Writers. I am not sure why that is not working in your case, but I would suggest trying the first soltuion suggested in the KB. It involves creating the datasocket item a certain way in LabVIEW, and more details are available in the KB.
Scott Y
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Message Edited by Daniel_Chile on 06-29-2006 03:05 PM

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>
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I found the answer

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Has anyone else ever had a problem where you had to perform 2 datasocket writes before the datasocket read would pick up the change?

I have a local VI that is simply a control that writes to the datasocket server whenever the control value changes.(the dataitem on the server is permanent - its initialized and never released by the server)
In the same local VI I have a datasocket read polling a different dataitem on the server.
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dingler44 wrote:
>
> Has anyone else ever had a problem where you had to perform 2
> datasocket writes before the datasocket read would pick up the change?
>
> I have a local VI that is simply a control that writes to the
> datasocket server whenever the control value changes.(the dataitem on
> the server is permanent - its initialized and never released by the
> server)
> In the same local VI I have a datasocket read polling a different
> dataitem on the server.
> The remote machine has a VI that reads the permanent dataitem on the
> server once per second.
> For some reason, after adding the local VI mentioned above, the
> remote VI stopped picking up the first change in the permanent
> variable.
> I'd start both the local and remote VIs...
> Then change the local control and the remote VI would not update -
> as if the datasocket write(upon adjusting the control) did not take
> place. So I'd change the control value again - this time the remote
> VI would update to this new value. And from here on out - the remote
> VI would update correctly. This problem only occurs when the local VI
> is first started up.
>
> What in the heck is going on?
Gorka is right, this came up on Info-LV a few days ago. Someone
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yet, but they are aware of it and will fix it. No anticipated release
date for the fix.
Regards,
Dave Thomson
David Thomson 303-499-1973 (voice and fax)
Original Code Consulting [email protected]
www.originalcode.com
National Instruments Alliance Program Member
Research Scientist 303-497-3470 (voice)
NOAA Aeronomy Laboratory 303-497-5373 (fax)
Boulder, Colorado [email protected]

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Multiple write operation on datasocket possible?

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