A question about Basic Serial Write and Read.vi

[dangzhe]

I tried to use Basic Serial Write and Read.vi to simulate the funtion of Hyperterminal, communicating between the pc and the device through COM port. The question I have is that, when I opened the vi, under the VISA resource name option, I cannot find the COM port my device used. I clicked the refresh buttion, but still, always only shows COM1. And when I entered COM7 (which I was using) by hand, and clicked run, it would show the error message:" Invalid resource specified, Parsing error".

Can anyone help me with this problem? Thanks a lot.

[Dennis_Knutson]

Valid resources will be listed in MAX. If you do not see a new port there, try disconnecting and connecting again. If it still does not appear, it's possible you have one of the few brands that does not work with VISA. I'm assuming this is a USB-RS232 adapter.I've had very good luck with brands that use the FTDI chip.

[dangzhe]

Thanks for your reply, Dennis.

Actually, the MAX I installed on my laptop cannot detect any ports. Everytime I opend MAX and tried to see the lists of devices and interfaces, it would report an error saying MAX database connection error. I have McAfee anti-virus software installed on this laptop, it's provided by my company. So my another question is whether it is this McAfee prhibits the MAX to detect the ports info. And is it true that without running MAX, I will not be able to use Labview to connect to the COM port? In that case, I will ask the IT department to uninstall the McAfee software.

Thanks again!

[Dennis_Knutson · Accepted solution]

Not a big fan of McAfee but I'm not sure if it's responsible. There is a KB article about how to fix it.

Until you fix it and the ports appear in MAX, you will not be able to use the ports in LabVIEW.

[GJDR]

I am having problems with the Basic Serial Write and Read.vi. I removed the Write part of the vi. I tested it but I obtained the error attached below. Please help me  Thank You! 

[Dennis_Knutson]

You should really have created a new thread since your problem is unrelated to the original. You could also have done a search for the error. A framing error indicates a mismatch between the com paramaters that you have set for the pc and what the instrument is set to.

[GJDR]

thank you  I am new here in forums :)) I do not know how to start a new thread  please help me on how to post one thank you :))

[RavensFan]

At the top of the LabVIEW board is a blue box with the words "New Message" written in it.