Language - LabVIEW

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LabVIEW LabVIEW ..., developed by National Instruments is a ...

Introduction

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Quick Downloads

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Getting started with LabVIEW

If you are new to writing code for Phidgets, we recommend starting by running, then modifying existing examples. This will allow you to:

  • Make sure your libraries are properly linked
  • Go from source code to a test application as quickly as possible
  • Ensure your Phidget is hooked up properly

Windows(2000/XP/Vista/7)

Description of Library Files

LabVIEW programs on Windows depend on two files, which the installers in Quick Downloads put onto your system:

  • phidget21.dll contains the actual Phidget library, which is used at run-time. By default, it is placed in C:\Windows\System32.
  • Phidget21COM.dll is the Component Object Model(COM) library and provides your project access to the Phidget ActiveX objects. Your compiler has to know where this file is, by default our installer places this file into C:\Program Files\Phidgets, so you can either point your compiler to that location, or copy and link to it in a directory for your project workspace.

If you do not want to use our installer, you can download both files and manually install them where you want; refer to our Manual Installation Instructions.

We include instructions on using our examples and writing your own code for the Microsoft Visual Basic 6.0 IDE.

LabVIEW

Use Our Examples

To run the examples, you first download the examples and unpack them into a folder. Here, you can find example programs for all the devices. If you aren't sure what the software example for your device is called, check the software object listed in the Getting Started guide for your device.

1. Open up the .vbp project into the Visual Basic IDE.

2. Next, navigate to Project → Components to ensure that your project has access to the Phidget ActiveX objects

File:VB6 Components.PNG

3. The Components menu will show up. Ensure that the Phidget COM library is selected. If it is not, then browse for Phidget21COM.dll and add it. By default, it is placed in C:\Program Files\Phidgets. Accept the changes.

File:VB6 Library.PNG

4. Navigate to Project → References and ensure that the Phidget COM library is selected.

File:VB6 References.PNG

5. The only thing left to do is to run the examples! Click on Run → Start.

File:VB6 Run.PNG

Once you have the Visual Basic 6.0 examples running, we have a teaching section below to help you follow them.

Write Your Own Code

When you are building a project from scratch, or adding Phidget function calls to an existing project, you'll need to configure your development environment to properly link the Phidget COM library. To begin:

1. Generate a new Standard EXE project.

File:VB6 New Project.PNG

2. Next, navigate to Project → Components to add the Phidget ActiveX objects into your project.

File:VB6 Components.PNG

3. The Components menu will show up. Browse for Phidget21COM.dll and add it. By default, it is placed in C:\Program Files\Phidgets. Accept the changes.

File:VB6 Library.PNG

4. Navigate to Project → References and ensure that the Phidget COM library is selected.

File:VB6 References.PNG

5. Navigate to Project → Project1 Properties, select the Make tab and ensure that the Remove information about unused ActiveX Controls checkbox is unchecked.

File:VB6 Unused ActiveX Controls.PNG

6. Then, you will need to declare and initialize the Phidget ActiveX object for your device.

The simplest method is to place the Phidget ActiveX object from the toolbox directly onto your form. If the toolbox is not present on your screen, navigate to View → Toolbox to show the toolbar. Next, find the ActiveX object for your device in the toolbox, and double click it to add it to the form.

File:VB6 Toolbox ActiveX.PNG

Alternatively, you can dynamically create the Phidget ActiveX object in code. For example, for an PhidgetInterfaceKit, you would type:

Dim WithEvents PhidgetInterfaceKit As PhidgetInterfaceKit

Private Sub Form_Load()
   ...
   Set PhidgetInterfaceKit = Controls.Add("Phidget21COM.PhidgetInterfaceKit", "PhidgetInterfaceKit")
   ...
End Sub

The object name for each type of Phidget is listed in the COM API Manual. Please see the examples on how to add a reference to your particular Phidget.

The project now has access to the Phidget function calls and you are ready to begin coding.

The same teaching section which describes the examples also has further resources for programming your Phidget.

Follow the Examples

By following the instructions for your operating system and compiler above, you probably now have a working example and want to understand it better so you can change it to do what you want. This teaching section has resources for you to learn from the examples and write your own.

Next comes our API information, with syntax for all of our functions:

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Example Flow

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Common Problems and Solutions/Workarounds

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