why do I get error -17502 when using datasocket step type in Test Stand

[dtraxler]

Tried to use the DataSocket step type DLL posted elsewhere on the NI site. After editing the URL and the variable the data goes into, I get "system error -17502".

The URL points at a tag, through an OPC server and is of the form "opc://localhost/RSLinx OPC Server/[HEUI-1]dintMyTag".

The connection between the OPC server and the target controller works fine....

Thanks in advance,

David

[Caroline Bright]

Hi David,

I went through the source code provided with the example and determined that the isue was occuring because of a problem with one of the funtions finding the uir used in the step type.  This error is probably because the example was created in much older versions of the software.  I am attaching a new dll as well as source code for you to use.  Just replace the old dll and c file with these files.  Also, you may need to go in and browse for one of the header files used in the program as its location has changed in the newer versions.  The file that may cause trouble is the stdtst.h file but you can just browse to it in its new directory C:\Program Files\National Instruments\TestStand 3.1\AdapterSupport\CVI.  Give these new files a try and let me know if you are still having any trouble.  I will be updating the online example to show these new changes.

[dtraxler]

Thanks, that fixed it.

There is one thing in the readme that comes with the example, that appears to be incorrect. The readme states "The data type of this variable must correspond to the type of data that you are reading from the server." The value I am reading is a defined as a double integer in the PLC (a signed long). When I use a local variable of type "number", I always get 0 back. If I change the type of this variable to "String", then I get the correct value. FYI...

The help is much appreciated.