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Simulation of a scope through IVI driver

Hello,

 

I am running a .VI which acquires data from a scope. I do not have the instrument scope connected, so I initialize it in simulation mode, while the scope is defined through an IVI driver. In this IVI driver settings, I have selected "simulate with" and I have chosen nisScope. 

 

When I run the .VI to acquire from the scope, I get a sinusoidal waveform. Even if I change the channel, I always get the same sinusoidal waveform. Also changing the "simulate with" option (other than nisScope) of the IVI driver, I always get the same sinusoid.

 

By reading the various tutorials, I thought that the simulated data should be random, so why am I getting always the same waveform? Some missing setting? 

 

Thanks.

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You are seeing the default simulation. Refer to http://www.ni.com/white-paper/4560/en/ for modifying the simulated data.
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Hello,

 

thanks for your answer. I already have read such guide as well as the IVI Driver User Manual, where there's a description of two possible ways of simulating data: 1) Specific Driver Simulation and 2) Advanced Class Driver Simulation. My understanding is that 1) corresponds to setting "Simulate with Specific driver" and 2) corresponds to "Simulate with niSscope" in the general IVI settings (in NI MAX). 

 

It's normal that in case 1) a sinusoid is returned, citing the manual: "When you use an oscilloscope-specific driver in simulation mode, the Read Waveform function returns a simple sine-wave array of data within valid ranges for the scope. This simple data generation process returns data values to the program variables so subsequent function calls do not fail for lack of data. However, a simple sine wave of fixed frequency might not be meaningful.". 

 

In case 2), citing the manual: "When your program makes a call to a class driver, the class driver calls the corresponding function in the specific driver. When you enable simulation, the class driver opens an additional session, a session that is assigned to its class simulation driver." So I was expecting that if selecting "Simulate with niSscope", then this additional session should open, while it does not. The manual mention that "Simulation drivers have two modes: interactive and non-interactive. You specify whether to use interactive or non-interactive simulation with the IVI Configuration utility. In interactive mode, simulation drivers have pop-up user interface panels that allow you to configure the parameters for generating the simulated output data" but I could not find where to select the interactive mode, although I checked everywhere the IVI configuration utility in NI MAX. 

 

As mentioned, whatever changes I make, if I set Simulation=1 in the Initialization, I always get the sinusoid, no matter which settings I apply in the IVI simulation configuration. Now, did I misunderstand the whole thing or what is the matter with this driver? I am using the hp548xx driver with a 54845A Agilent scope.

 

Thanks for your help. 

 

 

 

 

 

 

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A little update: I have found the initialization settings in the nisScope simulation driver session. Among these, I can set, for example, INTERACTIVE_SIMULATION to true (BTW, that should have been true already by default). However, by running the .vi I do not experience any change, no interactive window, and still the default sinusoid appears. 

 

There are also many other settings: on the manuals, I found that also the setting order is important, but I could not find a manual which explains parameter by parameter, and which ones are necessary for getting an interactive simulation (I wonder if INTERACTIVE_SIMULATION is enough).

I have also tried to change AMPLITUDE settings, but nothing changes in the simulated sinusoid. Maybe these parameters are not coherently set?

 

Anybody willing to clarify?

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I'm confused as to what you are doing. From what I know, NiScope is for the NI series of digitizers. The class driver is IVIScope. You say you are trying to simulate a 54825. Clarify please.
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Hello,

 

I am very sorry if my previous messages are not clear. Yes, I am trying to simulate a 54825a scope.

I have created an IVI logical name, which links to the hp548xx driver.  In the section simulate with, I have set nisScope. In the nisScope driver session, I have added the attribute INTERACTIVE_SIMULATION=True (although, this should be a default). 

 

In a VI, I run a VI that initialize the scope by passing the logical IVI name as handle. The VI runs, but the simulated waveform is always a sinusoid, while I was expecting the possibility to customize the returned data. If I set simulate with "specific driver", I get the same result. 

 

I hope that  this clarifies.. thanks in advance for your help.

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Hello,

 

I find this post and at this point, I have exactly the same problem. I just wanna no if you success to set up your configuration or if you try other things to simulate your device.

 

Thanks !

 

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