Impossible to use COM port

[Pizzocolo]

Hello to every newsgroup!

I have a very strange problem using RS232 COM port on a computer.

I wrote a program using LabVIEW 8.2 in which the serial port communicates toward an external device.  So: in my Windows XP development PC all works; in another NEW Windows XP PC I installed my program distribution kit and I was able to run the program and to communicate to my device; in another Windows XP PC I installed exactly the same distribution kit, but the program is unable to use the COM port!

I opened the MAX, and I saw the VISA is installed (v4.1), but the MAX found no serial port in the "Device and Interfaces"!!  I'm sure that both COM ports work, because using hyperterminal I’m able to use them.

I tried to uninstall the VISA and reinstall it. I also tried to upgrade the VISA at 4.2 version, but the program never works with the COM port.

Thank you to everyone who can help me.

Have a nice day.

[MikeS81]

Hi Pizzocolo

could it be that your com ports have an other numbering on your pc?

Mike

[Pizzocolo]

Hi Mike,

another numbering on my PC? I do not belive so: the 2 COM ports are the normal integrated COM ports and in "Device manager" I can see them as COM1 and COM2 port.

So I guess there is another reason.

Thanks.

[Chuck_81]

Hi Pizzoccolo,

is there some error message returned by your program? What do you mean when say "unable to use COM ports"?

Serial devices on Max are shown only if the NI-Serial drivers are installed on your PC; NI-VISA allows you to detect and use serial interfaces as VISA resource, but only with NI-Serial you'll be able to have them listed under MAX "Devices & Interfaces".

Hope this helps,

Fabio

[Dennis_Knutson]

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Fabio_81 wrote:

Hi Pizzoccolo,

is there some error message returned by your program? What do you mean when say "unable to use COM ports"?

Serial devices on Max are shown only if the NI-Serial drivers are installed on your PC; NI-VISA allows you to detect and use serial interfaces as VISA resource, but only with NI-Serial you'll be able to have them listed under MAX "Devices & Interfaces".

Hope this helps,

Fabio

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To use and view serial ports in MAX, NI-Serial is NOT required. I do not now, and never have had NI-Serial installed but built-in and USB->RS-232 ports are listed in MAX. The only time I ever had to install Ni-Serial was when I used an NI serial board.

[Chuck_81]

Yeah Dennis, I was wrong: NI-Serial are required for using Serial interfaces in MAX only when dealing with cRIO and other RT targets... Sorry for the wrong information!!

[Dennis_Knutson]

Unfortunately, I wish I had an idea of why the installation of just NI-VISA does not appear to work for the op's problem.

[Pizzocolo]

Hi Fabio_81,

hi Dennis,

the error I sow when I tried to open the COM1 is "Property Node (arg 1) in VISA Configure Serial Port (Instr).vi->TestCOM.vi" (Code "-1073807343").

This error is the same error that appears when I try to open a COM port that doesn't exist, but, I repeat, I'm sure that the COM1 exist (I able to use it in hyperterminal).

I guess the problem is not in my program (in other PC it works correctly), but it's due to MAX where I cannot see any COM port: I think LabVIEW is not be able to use the COM port (I don't know why).

Do you have other suggestion?

Thanks.

[IngoWolf]

I have a similar problem, I can't use TCP/IP on the non developer maschine

and tryed al the reinstallations you did, I have also no serials on this maschine

in max and can't add some, there is only pxi under devices.

I wish I would no what to install on the production maschiene.

ingo

[IngoWolf]

Somebody told me that installing full NI-VISA instead of RunTime may solve the Problem.

You can't download full NI-VISA but I've red that an NI-VISA deployment License is included

in LabView like in some Other NI-Development Systems.

So maybe installing NI-VISA from the LabView-CD/DVD will help, maybe complete with

MAX from there.

May be it is also possible to extract that Installation from the CD/DVD.