Problems with Windows NT and serialport

[Sami Kuusrainen]

Hello

What should I do when Windows NT and serial port read/write does not work?
My device send some bits to port (COM 1) and can be readed with hyper
terminal but that VISA thing is unable to read it. LabView version is 6i and
computer is portable IBM ThinkPad(300MHz).

Everything works fine with Windows ME.

Thanks,

Sami K.


--
ICQ#: 141602107
email: sami.kuusrainen@raketti.net

[GabbyG]

Did you check the the control lines (DTR, CTS, RTS etc.) NT might default the status differently and your device might require a certain value.
Are you receiving binary information? Labview will stop when a "termination character" is received and you'll have to check the buffer and start a new read to retrieve the rest.

Gabi

[Oleg]

Hi,
Are you shure that you have installed VISA drivers on your NT system?
When you setup LV it offers you to install VISA drivers. May be you forgot to check this option. In this case you will be able to see and use VISA vis in LV, but your programs will not work till the installation of VISA drivers.
Check it.

Good luck.

Oleg Chutko.

[Sami Kuusrainen]

> Are you shure that you have installed VISA drivers on your NT system?
> Oleg Chutko.

This error message looks like that there is something wrong on that visa
system: initialization of dynamic link library \system32\NIVISV32.dll
failed.

This error messages is always on my screen when i'm trying to use labview
and that serialread program. But... when i use application builder ( build
application on other computer) and install that builded program with that
run-time engine it looks like everythink works fine. No error messages,
program runs but serialport is still dead. Before install that application i
must uninstall labview first because of that error message.

>Did you check the the control lines (DTR, CTS, RTS etc.)
>Gabi

CTS/RTS line is dead t
oo, nothing happens when i'm trying to control it on
program. Device which is connected to serialport is showing when
CTS/RTS-lines state is changed. Now it shows nothing...

Any ideas?

Thanks,

Sami K.

[Dennis_Knutson]

It's pretty clear that VISA is not correctly installed on your NT system. Also, a built application does NOT include the VISA drivers unless you you manually add the VISA run-time engine as part of the installation. Your built app probably has the same error but the error is not being trapped so no message is being displayed.

[Rob Cole]

First, upgrade your version of LabVIEW to 6.0.2. I had to do this to get the serial ports working on my NT box. The update can be downloaded for free from the NI web site. Other than that - the other suggestions here sound about right.

Rob

[Jeremy Braden]

I agree with Rob that you should upgrade to LV6.0.2. It is free and can be found at www.ni.com >> download software >> drivers and updates >> all software versions >> LabVIEW >> winNT >> update >> LabVIEW 6.0.2 update for windows. I recommend also uninstalling and reinstalling VISA. You can get the driver from the website by choosing VISA instead of LabVIEW above. Finally, it would be helpful to know if you could get the shipping examples to work. They are located at the following place: open LabVIEW >> help >> examples >> i/o interfaces >> serial communications. Serial Communications.vi is a good diagnostic program.

Jeremy Braden
National Instruments