Serial port interrupt

I am a new user of LabView. I have been working a project for a month. I can explain shortly:
I used serial visa in my application. I configure all necessary thing for using serial port (port number, baud rate, etc.)
I configured the time out also, but I do not want to use it. Because when the time out finish serial visa read the port. If there is nothing
at the port read a empty string (""). It is a problem in my application.
I want to read the port when anything written. (when a interrupt occur)
May be it is just an easy problem but I could not find.
Thanks for your help.

Horseman,
I am trying to understand exactly what you are trying to do. If I understand you correctly, your code is wait for event is timing out and then it goes ahead and tries to make a read anyways. The read then returns nothing, so you would like your code not to read at all if it times out. Is this correct? In this situation, you would want to make a case statement that would have a case for when there was characters to read, and separate case for the time out to do nothing. Was that what you were looking to do?
Cheers,
-Marshall R
National Instruments
Applications Engineer
One stop for all your NI-VISA Support
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NI-DAQ Function Reference Manual for PC Compatibles
http://digital.ni.com/manuals.nsf/websearch/1630A0B68738B269862567C1007A2912?OpenDocument&node=132100_US
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Greetings from Germany!
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Hallo, Gilles,
Du meintest am 21.09.99 zum Thema serial port CTS monitoring:
> I would like to know how to read the status of the Clear To Send
> (CTS) line.
advanced/memory/in port
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Hi Magnetica
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Attachments:
advanced.JPG ‏31 KB

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... see the Solaris man pages.
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Ok this should be simple - if I understand you correctly.
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Hi florian
check the help examples
Attached png file shows the example.
chow
xseadog
Attachments:
serial.PNG ‏39 KB

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I can't feed those same bytes that show up as a correct hex representation
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I'm sure I'm staring the solution in the face, but I can't find any way to
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duh, well I finally discovered the "Unflatten from String" function. A guy
just feeds in the bytes he's collected from his serial port that Labview
thinks are a "string", and out come lovely little unsigned 16 bit numbers,
or whatever other type of number he wants to turn the bytes into. And there
are great little bit twiddlers available after that, like "swap bytes", and
you can mask out bits with the logic operators, why this is fun. There's
nothing like being a moron...... fly me to the moon...................
"David Lewis" wrote in message
news:[email protected]..
> The two bytes would come from a serial port read.vi in Labview, classed as
a
> string. For instance, D3 and 02. The output wou
ld swap the two bytes,
i.e.
> to 02 and D3, consider the two swapped bytes as 16 bits, drop the six most
> significant bits, and output the ten bits that are left as an integer
> classed by Labview as some kind of number, not a string.
>
> Your example StringToBits_Converter.vi I found on the ni.com site
> unfortunately gives an error message and refuses to open on my system
saying
> it comes from a newer version of Labview 6 than I am running. Mine says
> 6.0.1b3. Thank you very much anyway.
>
> "FightOnSCTrojan" wrote in message
> news:[email protected]..
> > In another words, you want to create a VI in which the input is 2
> > strings (i.e. AB) and the output is the converted array bits (e.g.
> > 1010101010101010)?
>
>

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Message Edited by Dennis Knutson on 12-19-2009 05:49 PM

Problem in using serial port.

I am using serial port to get data from a fusion splicer. The number of bytes at the port is 4096 but the read buffer of VISA read is empty. I am reading the same number of bytes. Can any one tell me what is the maximum size of VISA Read buffer? I am trying to put the contents of the buffer in a file. I am using labVIEW 6.1 on linux.I am also attaching the VI.
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S.Vijayalakshmi
Attachments:
serail_comm.vi ‏52 KB

Hey Viji,
In your application it looks like you are just checking to see how many bytes are at the serial port. Is it possible that your application is check for the serial data at the port before the data actually gets there. If you are looping this code as a subVI or just running it over and over it is possible that one of the iterations could occur faster than your device can write the information to the bus. In this instance you are checking the number of bytes at the port and there might not be any there yet. In this case the port reads 0 as you have designed it.
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Reading the serial port will give you a string. How you divide the channels depends on how the data was formatted before it was sent over the serial channel.
If you are designing the instrument, as it seems from your query, then you can set up any form you wish. If your data is always floating point numeric, you could use space or tab characters to separate data words. You could use and XML format. If the instrument is provided by a vendor, contact them for the protocol.
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I may not be perfect, but I'm all I got!

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Serial port interrupt

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