VeriStand Steps for TestStand Feedback

[User002]

Eisuke,

The Stimulus Profile is very similar to a light TestStand.  Both run on the host pc, but TestStand is far more powerful.  In addition, Stimulus Profiles cannot be called in a parameterized way, so they cannot be reused in a modular way.

Using variables is a workaround that might add some parameter passing capability to calling Stimulus Profiles, but as you said it is cumbersome.

The way we normally recommend is to use TestStand steps for most of the logic, and have TestStand call RT Sequences for deterministic tasks.  Since the Stimulus Profile is less flexible, we recommend using TestStand instead of it if you can.  The combination of TestStand and the Stimulus Profile should allow the greatest amount of functionality with the least pain in setting it up.

If your customer already has a library of Stimulus Profiles he wants to call from TestStand, there are two ways to go forward.  One is to use the method he is using, of using user channels to pass values to and from the Stimulus Profile (or more likely to the RT Sequences that the Stimulus Profile calls).  The other method is to rewrite the logic in TestStand.

Will this work for your customer?  If not, please explain more about what he is wanting to do, and I can give more specific recommendations.

Best Regards,

Andrew

[e.ono]

Hi Andrew.

Thank you.

Very Clear to me.

I guess the customer as well.

Thank you for your very kind support.

Best regards.

Eisuke Ono

[e.ono]

Hi Andrew.

Thank you for your kind support.

Let us confirm one more things.

>>The other method is to rewrite the logic in TestStand.

I am very happy if you tell us how to concretely rewrite the "logic"?

Best regards.

Eisuke AE at NIJ.

[e.ono]

Hi Andrew.

Our customer's in Japan, have following system requirements.

- A test system which runs during night or even on holidays.

- They would like to log the test results per test unit

- ATML file is generated per a stimulus profile so they would like to run stimulus profile from teststand.

They have following questions regarding the veristand steps.

1. Is it possbile to pass the return value from "RT Sequence Pass Fail Test" to Teststand variable? If possible, how?

2. Is there a parameter which determines the logging period (delta-t) for Start VS logging?

As a background, Start Logging Step for stimulus profile step could determine logging period (once a sec or 10 times a sec etc.) for logging steps so they compare it to teststand.

3.Is it possible to run several logging period using "Start VS logging"?

4. If "3." is possible, there should be a way to control which logging steps should be stopped using Stop VS logging?

5. "Open and Deploy RT sequence" is the recommended way to run Real time sequence?

They are asking the usage of "Pause RT Sequence" and "Abort RT Sequence" and "Stop RT Sequence".

6. "Get Sequence Return Value" steps get return value from Real time sequence.

Is this getting value from the Real time sequence, executed right before "Get Sequence Return Value"?

7. Is it possible to pass from "Get Sequence Return Value" to teststand variable?

I really appreicate your cooperation though, I understand you are busy.

Best regards.

Eisuke Ono

NIJ AE.

[Sarci1]

Hello Eisuke,

1. It is possible to pass the return variable from the RT Sequence Pass Fail Test. If you look at the Property Browser for the step you will see a Result.VeriStand.PassFail variable. This is the return value for the test. In the RT Sequence Numeric Limit Test the return value can be found in the Step.Result.Numeric variable.
2. In the current version of the steps we only support logging at the target rate. You cannot set the rate at which to log channels. The customer has the option to work with their local support engineers to modify the existing step to set up a custom rate. We will also note this as feedback for future versions of the steps.
3. Currently there is only support for a single log that can be segmented according to size. We do not support multiple logs at this time but have it on our roadmap for future development.
4. Since we only support one log at a time (meaning you have to call a Stop Logging before you call a new Start Logging step), we don't provide the ability to dictate which log to stop. Supporting multiple logs is on our roadmap for future development.
5. There are three recommended options for running RT sequences. Of the three there are two tests: RT Sequence Pass Fail Test and RT Sequence Numeric Limit Test. These tests evaluate the return variable. The other recommended option is to use the RT Sequence Action step (in the RT Sequence folder). This runs a real-time sequence a provide a result variable (under Result.VeriStand.Returnval).The steps you mention are a part of the Advanced palette and not recommended for first-time users.
6. See #5.
7. Instead of using the Get Sequence Return Value step, use the return values mentioned in #1 and #5. Then you can use a Post-Expression to set a variable to the appropriate return value container.

Best Regards,

Lynn

[tfelber]

I realize this is a very new Step Type Library and most of the functionality is pretty straight forward, however I have parsed through the discussions but have found nothing clear on how to get the "start stimulus profile session" to work.

I have seen discussions where someone said it works and others where someone said it won't work. I've tried the "NI VeriStand - Run Stimulus Profile.vi" from the "Run Stimulus Profile.llb" and the "Start Stimulus Profile Session" step type from the "Low-Level RT Sequence Controls" of the "NI VeriStand Step Types" for VeriStand 2013 SP1.

I am using VeriStand 2013 SP1, TestStand 2013 SP1, and LabVIEW 2013 (32-bit).

I can start my profile, which consists only of a VeriStand sequence which waits for a logging flag to be asserted and a set of parameters to log, and run it manually without issue.

[Sarci1]

Hi tfelber,

The step you are needing to use is the Run Stimulus Profile (or the async version) step in the Low-Level Stimulus Profile Control folder in the Advanced section. This will allow you to run a stimulus profile.

One item to understand is that TestStand was meant to replace the need for creating Stimulus Profiles. Instead it is recommended that you generate all non deterministic portions of your test in a TestStand sequence. Then, for any deterministic actions, use a real-time sequence to define this behavior. This will then allow you to RT Sequence Numeric Limit Test, RT Sequence Pass Fail Test (both in the VeriStand Tests folder), or the RT Sequence Action step (in the RT Sequence folder).

Best Regards,

Lynn

[e.ono]

Hi Sarci1.

Thank you for your quick response and kind support.

Our customer added some comments on the questions 1.

Instead of our customers, I asked following questions.

>>1. Is it possbile to pass the return value from "RT Sequence Pass Fail Test" to Teststand variable? If possible, how?

Sorry I misunderstood customer's intention. So the questions above "1." is a bit differenet than they thought.

Actually they were asking if they can control to run stimulus profile from Teststand and pass data to Teststand.

Is it possible to control to run stimulus profile from Teststand and pass data to Teststand?

I noticed that the comments above.

"One item to understand is that TestStand was meant to replace the need for creating Stimulus Profiles. Instead it is recommended that you generate all non deterministic portions of your test in a TestStand sequence."

But, I am a bit confused.

If the customer have already created many stimulus profiles, they can not re-use them.

Is there a way to control to run stimulus profile from Teststand and pass data to Teststand?

Best regards.

Eisuke.

[Sarci1]

Hi Eisuke,

Like I mentioned in the previous post you can use the Run Stimulus Profile step to run an already existing stimulus profile. At this point we don't have support for passing the execution results for stimulus profiles back to TestStand. The customer has the option to work with their local support engineers to modify the existing step to add this feature.

Best Regards,

Lynn

[tfelber]

I have tried the Run Stimulus Profile step with no success.  What I am trying to do in the stimulus profile is log a bunch of channels I. Realtime.  I can't think of a way to do this from TestStand.  I also want the ability to start/stop logging, which I implemented using a discrete trigger.  Since there is no looping functionalty in the stimulus profile and the veristand sequence can't start logging I have just created a multitude of "Wait for Trigger (True)", "Start Logging", "Wait for Trigger (False)" statements.

I have also noticed some annoying behavior within the stimulus profile editor, such as:

- Shift Select doesn't select block of lines, only the first line and the current line

- Ctrl Select selects a combination of lines but when you paste they are pasted in the order they were selected rather than the order in the selected block.

- Paste can only be done at the beginning of a section.

Thanks,

Tony