Simulate a test program at system level

[BenoitProvost]

Hi,

  Is there a simulation tool or methodology that can be used to simulate a TestStand test program? I could create a behavioral model of the Device Under Test, but the difficulty I see is the interfacing of the model with the instrumentation drivers. For example, if I use a NI-DAQ card, is there a way to control the inputs of the DUT VI in the program? Same for the DUT model outputs: Is there a way to send signals to the NI-DAQ instrument driver input by software, and make the driver "believe" it was a real signal coming from the hardware NI-DAQ?

  This would be very useful for two reasons:

  - Development of the test programs before the real DUT becomes available

  - Troubleshooting of the TestStand and Labview programs on a user PC, instead of monopolizing tester hardware

  Thanks,

  Benoit

[Dennis_Knutson]

DAQmx has some simulation capability. You can program whatever you want for DAQ output and check for errors in code. The simulated analog read is fixed as a sine wave and cannot be changed. If you are using IVI, you can use the simulated option when doing the initialize. What you can specify as a simulated input is dependent on the instrument specific IVI driver and what capabilities were provided by the author of the driver.

[dowNow]

Hi,

As Dennis said DAQmx and IVI both have simulation capabilities and though I don't use them much I think they are both really  capable. You mentioned modelling the UUT, I don't think the driver simulation features will provide the detailed response of your UUT.

What I wanted to add is, you can use the None adapter in TestStand to create simulated steps that can create data using expressions if you just want to figure out your test execution flow control, results collection, barcoding, pass-fail action, database interface, etc. This type of simulation would be just at the test management layer, and UUT-related sim is at the LabVIEW layer.

cc

[BenoitProvost]

Thank for the suggestions.

We are currently using VISA drivers for all our instruments, not IVI. Last time I downloaded an IVI driver update by mistake, I had to fix all instrument handles by hand, until I realized I had to use the VISA version instead. So I am not sure I want to convert everything at this point. Is there an easier way to convert from VISA to IVI?

Thanks,

Benoit

[Dennis_Knutson]

You would have to change a lot more than just the instrument handles since the functions in a IVI class driver are not going to be the same as a plug and play driver and no, I know of no easy way to do that.