COM port problem

[Izze2000]

Hi Gents,

Sorry a really newbie question but i cannot get the VISA serialport to work.

When i use Hyperterminal and other sw i can read from the COM4 without any problems. I.e. the hardware works.

But when i run the "Basic Serial Read and Write.vi" i get a strange "-1073807202" error message?

I get the same message when i dive into the "VISA Configure Serial Port (Instr).vi" trying several COM ports etc.

Any hints?

Btw im running Labview 8.2 on a Vista machine.

Thanks!

[smercurio_fc]

That usually means you don't have VISA installed. Launch MAX (Measurement and Automation Explorer and expand the tree item My System->Software. Verify that NI-VISA is there. If you don't have MAX or NI-VISA, rerun the installer and install VISA.

[Shivkumar]

Izze2000 ,

   For this problem problem as the above reply states visa is not installed, what you can do to rectify this error is installing the driver CDs to get the NI VISA.

Sivakumar G

[Izze2000]

smercurio and Shivkumar!

Thanks you where completely correct! VISA was missing under software in the Measurement and Automation Explorer.

Now i have installed the VISA, reeboted the computor but strangely enough i get the same err  message?

Under NI-VISA i can find,

visa32.dll

NiVisaServer.exe

NIvisaic.exe

Any more hints you can think of?

Many thanks!

[smercurio_fc]

What are you using as your VISA resource name? It should be in the form ASRL[board][::INSTR] (note that the characters [ and ] are placeholders). In your case it would be ASRL4::INSTR.

[Izze2000]

Ok!

I have tried both COM4 and now ASRL4::INSTR as you mentioned, thanks.

I also probed the VISA recource name in the Diagram view where COM4 alt. ASRL4::INSTR shows up in the "VISA refnum"

still no cigarr

Also when i do a refresh in the Visa recource name no COM ports shows up?

[Dennis_Knutson]

Before you even think of using LabVIEW, make sure that the com port is being shown in MAX. Expand the Devices and Interfaces>Serial and Parallel and see if the port is listed there. LabVIEW will get the resources from what MAX finds.

[Izze2000]

...i checked MAX as you said. The COM ports are there, seems to be ok.

Now when i got back to Labvie the vi suddely works

Q: did the port checking in the MAX initiate the ports or, just curios?

Anyway, thanks alot guys guys!!.....now i  need to start to do some programming

[Dennis_Knutson]

Going into MAX forced it to do a refresh and to check for new resources. Glad it's working now.