VISA Errors on Configure Serial Port

[Kezar]

I am using the attached VI to aquire data from a Cognex Dataman 100 barcode scanner.

For a small percentage of the times I run the VI, I get one of the two following errors;

-1073807360 - Property Node (arg 1) VISA Configure Serial Port

-1073807330 - Property Node (arg 2) VISA Configure Serial Port

I can add error handling to retry on this error, but I would like to understand why VISA is throwing this error.

Thanks

[Chris G in AE]

Howdy Kezar,

Here are the definitions of your errors from the LabVIEW Help file:

−1073807360  =  Unknown system error (miscellaneous error).
−1073807330  =  The specified state of the attribute is not valid, or is not supported as defined by the resource.

These errors are being generated by something in your VISA Configure Serial Port, most likely an improperly configured stop bit.  Check out this KB to see how to go about fixing this error.  Good luck!

[Kezar]

Thanks for the reply.

I have read the KB article you have referenced, but I do not believe this applies to my problem.  I do not have anything connected to this terminal, as I am using the default value.

Thank you

[K C]

Hi,

I don't think the number of stopbits can give you an error unless bytes are directly send after each other and the number of stopbits is 2

With the default setting of one stopbit it should always work.

Did you try this on a different PC, it looks more like a hardware error to me.

How often do you call this VI ? If it is a part of a program then it would be better to open and close the port in your upper VI.

[Kezar]

This error occurs on several machines.  I have the same block of code on 4 workstations now, and will be adding 5 more within the next month.  I've added code to e-mail me when this error occurs, so I will begin collecting frequency by workcenter data.

For background information, the calling VI is responsible for capturing a serial number which is contained in a barcode.  The calling VI is dynamically called from the Top-level application.  It is dynamically called because there are other methods in which a barcode can be collected (OPC communication with a PLC, RFID query, etc) based on the workstation.  I have created a plugin for each of these methods.

For workstations that use this barcode read, the VI is called frequently; as much as once every 5 seconds.  Additionally, when it is called, it is not known if it will be called again.  I would rather not complicate my top-level VI with dynamic calls to deallocate resources that may not be used for the other plugins.  Also, I view this solution as a work-around, in which I already have one; ignore the error as it is not critical.

Thank you