How can I use low level driver from teststand through CVI?

[Hiren]

I am trying to control the serial port by outp command. I have code written in CVI and calling that dll from TestStand. I have low level drivers on the PC but it can not load that and I can not control the serial port.

[Elaine_R.]

Hello Hiren -

As a way of troubleshooting this behavior, have you tried writing a quick CVI EXE that can call this DLL code to make sure that the DLL is loading and linking correctly in general? Another thing to try would be to use the CVI debugging option 'call external executable' for your DLL's project and have CVI launch the TestStand seqEdit.exe as part of the CVI execution. This way you could step into your dll at runtime and try and get a more precise fix on where the breakdown is happening. If you could provide any results from trying these two things, it would be very useful to us in debugging your application further. We will investigate this here as well.

--Regards,

Elaine R.
National Instruments
http://www.ni.com/support

[Hiren]

Hello Elaine,

I have got the solution for this problem. To access the low level drivers for rs232 port you have to open that port first. You don't have to do anything to access the parallel port.

Thanks for your help.

Regards,
Hiren