An error about reading serial port

Hi,
I have sent 5 bytes(for example: "0","2","F","1","/n") to serial port and used VISA Read. But I only can read 0. The right result is in the second line of the read string window, The first line is void. Generally speaking, "02F1" should in the first line,then I can read them correctly. The following picture is the result.
Thank you!
帖子被hengfo在09-17-2007 03:57 AM时编辑过了
Attachments:
read string.JPG ‏6 KB

Hello,
you should add a flat sequence with some extra e.g. 50ms delays between the visa writes and reads, that helped us a lot.
You should also specify a large enough buffer. And don't forget to send the terminating CR and LF.

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Attachments:
MKSRead.vi ‏55 KB

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Attachments:
MKSRead_mod.vi ‏68 KB

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Sent via Deja.com http://www.deja.com/
Before you buy.

[email protected] wrote:
>
> Hi all,
> I have developed a VI that controls a setellite receiver using RS232
> serial port (LabVIEW 5.1.1).
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> I have already put serpdrv and my_file.ini files in the same directory
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> the problem.
> Any help greatly appreciated.
>
> Regards
>
> Antonio
>
> Sent via Deja.com http://www.deja.com/
> Before you buy.
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Roland Lampka - Nortel Dasa - ESN 565-7257 - FAX 8160

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Attachments:
NI Spy - before freeze.JPG ‏104 KB
NI Spy - after freeze.JPG ‏108 KB

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Message Edited by Dennis Knutson on 01-22-2010 01:42 PM
Attachments:
Parse String.png ‏16 KB

Error while reading USB Port : using JSR80

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Build Error: "VISA Configure Serial Port"

Hi,
I want to upgrade some old 6.i vi's to 8.5
But on building the project i am getting an Error:
Please take a look in to the screenhots
Greetings from the lake of Constance, Germany
juergen
=s=i=g=n=a=t=u=r=e= Click on the Star and see what happens :-) =s=i=g=n=a=t=u=r=e=
Attachments:
MESSAGE.jpg ‏106 KB
VI-LIB.jpg ‏783 KB

Hi j_dodek, there is a function called "mass compile", did yoou already try this option?
Please select Tools»Advanced»Mass Compile and choose the directory containing your old VI's. This will upgrade all the files in the directory or library.
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http://digital.ni.com/public.nsf/websearch/654877E62A97B72986256C95006F9B24?OpenDocument

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I open the example serial.vi , I select write to serial port, run the programm, I don`t have any problem. But when I select read serial port, I get the error code 16392and hex code error x4008. I need to know what can I do? Thanks a lot

Any time you get an error in LV you can right click on the error cluster indicator and do a "Explain Error".
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I have two instruments on serial ports, and two independant VIs to control them. One VI may be running, or both, at any one time. The VIs may be running under LabView, or executables.
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CDancer a écrit:
Thanks, guys, but I don't think you have understood my problem. Read the first sentence - 2 completely independant VIs, and 2 or more ports...
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ViLabWorks a écrit:
It isn't exactly clear to me why this is about one port. How much does one serial port cost versus programming time? Or even if it is about 4 serial ports the same applies. For me there is no question, doing something perhaps difficult versus spending next to nothing to solve the problem.
Well...
Sometimes you need to access the same equipement from different places in your application, or from different applications...
Usually I simply set/read a global "busy" boolean.
One problem I would like to adress is the automatic detection of specific serial hardware. How is it possible to find the port on which some equipment has been connected ? Of course, a solution would be to try to connect to this equipment by sending a command and waiting for the proper answer. However, before doing that, you need to detect the available ports (VISA Find Ressource), then scan each port after setting the proper baud rate, byte length, parity, etc..., then close the port to make it available to another application. Unfortunately, within LabVIEW, this procedure may interfere with other vis already connected to other serial equipments, with impredictable results.
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Chilly Charly (aka CC)
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An error about reading serial port

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