property node of "simulate arbitrary signal"

[SnowBoy111]

Very important issue.

I am using Labview 8

Windows Xp

PCI-GPIB Card

I need some help regarding access of property node of "Simulate Arbitrary signal" express VI.

My objective is to access "Load Data " button from Front Panel with out going into Block Diagram and double clicking the "Express Vi (Sim Arbtry Signal)".

How to access the Load data Property from Front Panel ?

Haider

Manager Tech (National Engineering)

[smercurio_fc]

Cross posted in Instrument Control forum.

Please do not cross post.

[smercurio_fc]

Your question is not clear. What "Load Data" button? The Express VI doesn't have a "Load Data" button. At least not in the 8.2 version that I'm looking at.

[Speedy_Badger]

Hello Haider,

I believe you are referring to the Load option within the properties of the express VI. The strength of an express VI is that it provides a concise solution to common applications. A trade off for the ease of use is that you sacrifice a lot of the lower level control. The "Simulate Arbitrary Signal" express VI in particular does not have access to the lower level property nodes.

If you are interested in programmatically controlling lower level properties you would be better off using the VIs that go along with File I/O and waveform simulation, rather than the express VIs. You can find these VIs in the File I/O and Waveform palettes.

Regards,

[smercurio_fc]

Ah, he was actually referring to the sub-dialog that you get when you click the "Define Signal" button. That is actually calling a subVI called "ex_TableInputs" located in the "vi.lib\express\express shared\" directory. You can call that VI yourself rather than using the Express VI. The "Load Data" button reads in a .lvm file, which you can also read using the "Read From Measurement File" Express VI.

[SnowBoy111]

Attachment (GPIB TEST EXPER . PSPT. VI)

                                        PS=STATIC PRESSURE

                                        PT=TOTAL PRESSURE

Thanks,

It helped me a lot to dig into subVi calling from the "express shared " directory.

1- Actuallly we have built all of our code which communicates with intrument(pressure simulator DRUCK AIR DATA TEST SYSTEM (having to pressure ports ps, pt)) using GPIB card. .

where we instruct the instrument to write a series of pressure values (reading from file or Table of "Define signal box") after each value is stable at instrument end ,

Code  is working fine . But end user is saying that hide the block diagram , and operate  all things from Front Panel to avoid unnecessary changes. So , to load the file we have to go to the Block diagram and double click the "Sim Arbtr Signal "express VI. we want to skip the block diagram and load the file from Front Panel .

There is another option by "Read Mea File" but it have no "Next Value " input parameter.

on the other hand as you told me that call the "ex_Tableinput" yourself. but it acts like an ActiveX control creating an another new instance , not changing to current express VI outputs.

[SnowBoy111]

correction

(having TWO  pressure ports ps, pt )

[Dennis_Knutson]

Your block diagram is a bit too large and the wiring messy but all you are getting out of the Simulate Arbitrary Signal is a 1D array. With a front panel Boolean and the Read From Measurement File or Read From Spreadsheet File, you should be able to do everything you want.

[Jennifer_R]

Hi Haider,

You can access the properties in the configuration dialog box by converting the "Simulate Arbitrary Signal" Express VI to a standard subVI:  

1. Place the "Simulate Arbitrary Signal" Express VI on the block diagram.

2. Configure the Express VI.

3. Right click on the "Simulate Arbitrary Signal" Express VI and select "Open Front Panel." 

4. "Convert" to a standard subVI.  Once it is converted, you can no longer access the configuration dialog box.

5. Replace the data array with the "Read From Measurement File" Express VI.  (You will need to use "Convert from Dynamic Data" to convert the signal to an array.)

6. Create a control for File Name, and now you can choose the file from the front panel. 

Hope this helps.