Signal Express Error: The session handle is not valid.

[AshishMaharjan]

I am generating and sending stimulus signals to PXI-6552 channels using NI-HSDIO stimulus/response tool. I used waveform created in NI Digital waveform as a source of signals. Then I used NI-HSDIO acquire to receive(or read) signals from those channels back. Then I used Save HWS tool to save the acquired signals.

The error I got was : The session handle is not valid.

I need to know the sample number at which my signals in different channels do not match. I hard-wired Channel 0 and 1 and compared the sent sginal from CH0 and received from CH1. Similarly I hard wired CH2 and CH3.

Any idea or suggestion?

Thanks.

Softwares used: Signal Express 2.5.1

                            Digital Waveform Editor 3.0

P.S. It didn't allow me to upload digital waveform file. *.hws extension not valid!!!

[Coal_Man]

Ashish,

The reason you are receiving the session handle is not valid error is because the stimulus/response step that you are using in your Signal Express project is using the same resources as your acquisition step.  The stimulus response step will only look to see if the device is already reserved by itself, not an acquisition or generation step.  Since you are only allowed to have one acquisition and one generation session per device, you will receive an error from one of these steps as you have seen.  This is a little more difficult to see since the stimulus/response block does not check for acquisition or generation sessions in the project.

As for the second problem you were having with saving the HWS signal, I did not see this error once I selected a file path that existed on my system.