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[[File:icon-LabVIEW.png|64x64px|link=|alt=LabVIEW]] LabVIEW ..., developed by [http://www.ni.com National Instruments] is a ...


__TOC__
We provide support for LabVIEW on the '''Windows''' operating system. By using LabVIEW, you will have access to the complete {{Phidget22API}}, including events. We also provide example code in LabVIEW for all Phidget devices.


==Introduction==
LabVIEW is a development environment for a graphical programming language created by National Instruments.


{{LanguageSupport|LabVIEW|the complete Phidget API, including events|all Phidget devices.| Windows. OS X and Linux are unsupported as Phidgets have not been tested on those systems.|}}
==Setup Guide==
 
<div class="phd-deck-sequence">
==Quick Downloads==
__NOTOC__
{{QuickDownloads|Visual Basic 6.0|
{{PT3_LABVIEW_WIN}}
{{APIQuickDownloads|http://www.phidgets.com/documentation/LabVIEW_Manual.pdf}}|
{{ExampleQuickDownloads|http://www.phidgets.com/downloads/examples/LabVIEWx86_2.1.8.20120216.zip| for 32 bit systems on Windows, OS X, and Linux}}
{{ExampleQuickDownloads|http://www.phidgets.com/downloads/examples/LabVIEWx64_2.1.8.20120216.zip| for 64 bit systems on Windows only}}|
{{WindowsQuickDownloads}}
{{MacQuickDownloads}}
{{LinuxQuickDownloads}}
}}
 
==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:
{{ExampleCodeReasons}}
 
==Windows(2000/XP/Vista/7)==
 
===Description of Library Files===
LabVIEW programs on Windows depend on two files, which the installers in [[#Libraries and Drivers|Quick Downloads]] put onto your system:
* <b>{{Code|phidget21.dll}}</b> contains the actual Phidget library, which is used at run-time.  By default, it is placed in {{Code|C:\Windows\System32}}.
 
If you do not want to use our installer, you can download the [http://www.phidgets.com/downloads/libraries/phidget21-x86_2.1.8.20110615.zip {{Code|phidget21.dll}}] and manually install it where you want; refer to our [[Manual Installation Instructions | Manual Installation Instructions]].
 
We include instructions on [[#Use Our Examples | using our examples]] and [[#Write Your Own Code | writing your own code]].
 
====LabVIEW====
 
=====Use Our Examples=====
 
To run the examples, you first download the examples found in the [[#Example Code | Quick Downlods]] section and unpack them into a folder. Here, you will find the {{Code|examples}} folder, which contains {{Code|vi}} programs for all the devices. Each {{Code|vi}} demonstrate the usage of a few of the device's properties. To get a broader understanding of the device, you should take a look at all the examples inside the directory for your device. If you aren't sure what the software example for your device is called, check the software object listed in the [[Device List | Getting Started guide for your device]].
 
1. Inside the {{Code|examples}} folder, navigate to the directory for your device.
 
2. Open up any {{Code|.vi}} of your choice in LabVIEW.
 
[[File:LabVIEW Win Front Panel.PNG|link=|alt=Front Panel]]
 
You will see the front panel of the example. The front panel shows the user interface of the {{code|vi}} program.
 
2. Next, let us take a look at the block diagram by navigating to {{Code|Window &rarr& Show Block  Diagram}}.
 
[[File:LabVIEW Win Block Diagram 1.PNG|link=|alt=Block Diagram]]
 
The block diagram shows the logic of the application.
 
[[File:LabVIEW Win Block Diagram 2.PNG|link=|alt=Block Diagram]]
 
3. The only thing left to do is to run the examples! Navigate to {{Code|Operate &rarr& Run}}.
 
[[File:LabVIEW Win Run 1.PNG|link=|alt=Run]]
 
4. The application will now run.
 
[[File:LabVIEW Win Run 2.PNG|link=|alt=Run]]
 
You can determine that your device is connected to your application if you see the indicator for {{Code|attached}} turn green and the correct serial number is displayed. These features are available in most of the example {{Code|vi}}s' we provide.
5. When you are ready to terminate the application, click on the {{Code|STOP}} button to release the hold on the device.
 
Once you have the LabVIEW examples running, we have a [[#Follow the Examples|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|link=|alt=New Project]]
 
2. Next, navigate to Project &rarr; Components to add the Phidget ActiveX objects into your project.
 
[[File:VB6 Components.PNG|link=|alt=Components]]
 
3. The Components menu will show up. Browse for {{Code|Phidget21COM.dll}} and add it. By default, it is placed in {{Code|C:\Program Files\Phidgets}}. Accept the changes.
 
[[File:VB6 Library.PNG|link=|alt=Library]]
 
4. Navigate to Project &rarr; References and ensure that the Phidget COM library is selected.
 
[[File:VB6 References.PNG|link=|alt=References]]
 
5. Navigate to Project &rarr; Project1 Properties, select the {{Code|Make}} tab and ensure that the {{Code|Remove information about unused ActiveX Controls}} checkbox is unchecked.
 
[[File:VB6 Unused ActiveX Controls.PNG|link=|alt=Unused ActiveX Controls]]
 
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 &rarr; 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|link=|alt=Accessing Phidget ActiveX objects from the toolbox]]
 
Alternatively, you can dynamically create the Phidget ActiveX object in code. For example, for an PhidgetInterfaceKit, you would type:
 
<div class="source">
<syntaxhighlight lang=vb>
Dim WithEvents PhidgetInterfaceKit As PhidgetInterfaceKit
 
Private Sub Form_Load()
  ...
  Set PhidgetInterfaceKit = Controls.Add("Phidget21COM.PhidgetInterfaceKit", "PhidgetInterfaceKit")
  ...
End Sub
</syntaxhighlight>
</div>
</div>
The object name for each type of Phidget is listed in the [http://www.phidgets.com/documentation/COM_API_Manual.pdf COM API Manual]. Please see the [http://www.phidgets.com/downloads/examples/VB6_2.1.8.20120131.zip 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 [[#Follow the Examples|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:
{{UsingAPhidgetInCodeGeneral|both of which are available in Visual Basic 6.0|[http://www.phidgets.com/documentation/COM_API_Manual.pdf COM API Manual]}}
===Example Flow===
{{ExamplePseudocode|In Visual Basic 6.0, you can name these '''event''' functions whatever you like.  You will then pass them as function pointers to the Phidget library below in the Main Code section.  This hooks them into the actual events when they occur. <br>
In the example code, the event functions common to all Phidgets are called things like '''AttachHandler()''' and '''DetachHandler()''', etc.<br><br>
Some event functions will be specific to each device, like when a tag is read on an RFID board, or when a sensor value changes on an Interface Kit.
Other functions are given in the examples to show you more detail on using your Phidget.  For example, '''DeviceInitialize()''' will show what needs to be set up for your Phidget before using it.
|Creating a Phidget software object in Visual Basic 6.0 is specific to the Phidget.  For a Phidget Spatial, for example, this would involve creating a PhidgetSpatial object.  The examples show how to do this and other API functions|
[http://www.phidgets.com/documentation/COM_API_Manual.pdf COM API Manual]}}
==Common Problems and Solutions/Workarounds==
{{KnownIssues|Phidgets do not always work cleanly in Labview.  Sometimes they do not appear, sometimes they work veeerrryyy slowly.  No known fixes yet, hopefully soon.}}

Latest revision as of 21:42, 10 August 2023


We provide support for LabVIEW on the Windows operating system. By using LabVIEW, you will have access to the complete Phidget22 API, including events. We also provide example code in LabVIEW for all Phidget devices.

LabVIEW is a development environment for a graphical programming language created by National Instruments.

Setup Guide

Language - LabVIEW

Windows with LabVIEW

Welcome to using Phidgets with LabVIEW! By using LabVIEW, you will have access to the complete Phidget22 API, including events. We also provide example code in LabVIEW for all Phidget devices.

LabVIEW is a development environment for a graphical programming language created by National Instruments.

Requirements

First, make sure you have the following:

● Phidgets Drivers for Windows installed(see Part 1 of this user guide)

● Phidget LabVIEW Library downloaded


Note: The LabVIEW Library also contains example VI trees, which we'll cover later in this guide.

Using Our Examples

One of the best ways to start programming with Phidgets is to use our example code as a guide.

Unpack the Phidget LabVIEW Library and rename the unpacked folder to Phidgets.

Using Our Examples

Navigate to the following directory:

● For 32-bit LabVIEW, C:/Program Files (x86)/National Instruments/LabVIEW 20xx/instr.lib

● For 64-bit LabVIEW, C:/Program Files/National Instruments/LabVIEW 20xx/instr.lib

Place the renamed folder at this location:

Using Our Examples

Next, open LabVIEW and create a new VI:

Using Our Examples

In the new block diagram window, open the functions palette (View -> Functions Palette).

Next, go to the Phidgets palette (Instrument I/O -> Instrument Drivers -> Phidgets):

Using Our Examples

Next, select a palette that will work for your Phidget and drag VI Tree.vi onto your block diagram:

Using Our Examples

Right-click on VI Tree.vi and select Open Front Panel:

Using Our Examples

From the front panel, navigate to the block diagram (Window -> Block Diagram):

Using Our Examples

The VI Tree Block Diagram lists all VIs available for its Phidget Class, and which subpalette to find them under. The examples are located near the bottom of the block diagram. Right-click the example you would like to use and select Open Front Panel:

Using Our Examples

When you are ready, press Run and the application will demonstrate the Phidget's functionality.

Here is an example of an Accelerometer channel on a Spatial Phidget:

You should now have the example up and running for your device. Play around with the device and experiment with some of the functionality. When you are ready, the next step is configuring your environment and writing your own code!

Configure Your Environment

First, we recommend enabling the Show constant labels setting in LabVIEW. This setting will reduce complexity when developing, and is especially recommended for beginners.

To enable the setting, first navigate to Tools -> Options on your block diagram:

Configure Your Environment

Select the Environment category and enable Show created constant labels at the bottom:

Configure Your Environment

To begin working with Phidgets, you will need both a StartPhidget VI and a ClosePhidget VI:

Configure Your Environment

Select a class that will work with your Phidget from the drop-down menu for each VI:

Configure Your Environment

You can now add device information or any initialization parameters to the StartPhidget VI. Using your mouse, hover over each of the connection nodes to see information about it:

Configure Your Environment

If you would like to add device information or initialization parameters, right-click the connection node and navigate to one of the following:

● Create -> Constant

● Create -> Control

Configure Your Environment

Creating a constant will allow you to modify device information from the block diagram:

Configure Your Environment

Creating a control will allow you to modify device information from the front panel:

The environment now has access to Phidgets. Next, we'll walk through writing your own code.

Write Code

Along with this guide, your main resources for writing LabVIEW code will be:

● The examples

● The Phidget22 API

● The VI help files

Examples of more complex general topics such as using multiple Phidgets and connecting to a Phidget over the Network Server can be found under the VI Tree for the Phidget Common palette.

Example Flow

Most LabVIEW examples follow the same basic flow: starting a Phidget, reading some data, and closing the Phidget.

Step One: Initialize, Open And Wait For Attachment Of The Phidget

The entire process of opening and initializing a Phidget can be done by using the version of StartPhidget.vi that corresponds to your device. In most cases, StartPhidget.vi will also attempt to wait for the first data to become available from the device for 5 seconds after initialization.

If you'd prefer to initialize the device manually, you can use OpenPhidget.vi for your device and call the individual functions to set up the device.

Step Two: Do Things With The Phidget

You can read data and interact with your Phidget both by polling it for its current state (or to set a state), or by catching events that trigger when the data changes.

To poll devices, simply place the corresponding blocks:

To use events, there are three main blocks for each type, to create, execute, and close the event handler. When creating the event, all devices using an event of the same type must be grouped into an array to ensure the events get processed correctly.

Step Two: Do Things With The Phidget

Once created, the events will be processed by [Name]EventExe.vi. When an event occurs, the pertinent information will be output, as well as information to reference which device caused it.

After a program has run its course, the event handler must be closed.

Step Three: Close And Delete

Closing a Phidget is done by using the appropriate version of ClosePhidget.vi

That's all the basic building blocks you need to create a LabVIEW program using Phidgets.

Help and Documentation

For more information on the use of any VI and its parameters, right-click the VI and select Help

Help and Documentation

This will take you to an HTML page outlining the function of the VI. This includes a list of all its parameters, which devices support them, their range of acceptable values, and their default values, where applicable:

What's Next?

Now that you've set up Phidgets in your programming environment, you should read our guide on Phidget Programming Basics to learn the fundamentals of programming with Phidgets.

Continue reading below for advanced information and troubleshooting for your device.

Scroll down for device-specific troubleshooting, or go to the next slide for LabVIEW troubleshooting.

LabVIEW Troubleshooting

Expand All
I cannot attach to an object any more after running my program once

What this means is you probably aborted the VI which stopped the program before the Phidget could be closed. Aborting execution will not release the Phidget device properly and will consequently make it unusable until the Phidgets library (or LabVIEW) has been restarted.

To resolve this, you may open a new VI, place PhidgetResetLibrary.vi, and run it. This will completely reset the current Phidget library, making it possible again to connect to all Phidgets.

Note that this action will close all Phidgets that are currently open in LabVIEW, and should not be used while other Phidgets-related LabVIEW VIs are running.

Phidget Reset All Palette.png

Phidget Reset All.png

In order to prevent this from happening you should use a software stop button when possible instead of halting operation. That way the Close subVI gets called and the Phidget will be released.

I cannot find my error code on this website

All Phidgets-based error codes in LabVIEW are offset by 7000 to avoid conflicting with LabVIEW's own error codes. To get the equivalent Phidget return code from the LabVIEW error code, simply subtract 7000. For instance, error code 7003 in LabVIEW translates to Phidget Return Code 3.

To find the meaning of all Phidget Return Codes, you can go to the Phidget22 API page, and open the PhidgetReturnCode section under Enumerations.

Events Can Occasionally Cause Issues, Especially When There Are Multiple Of The Same Type Of Event

In other words, if you open 2 of the same device and have a sensor change event for each one your system can behave unpredictably. This problem is a quirk in the way that LabVIEW handles passing events to and from C. There are a few solutions to this issue, either:

  • Stop using events and simply poll the device. Events work similarly to polling in LabVIEW anyway and should not cause substantial performance changes to your application.
  • Implement a simple fix to the events which are causing the problem. The pointer is identical in the case where two events of the same type are passed from a single function. This causes the events in C to output to the same event in LabVIEW. To get around this you need to copy the offending subVI, then change the name of the cluster object in it from "Event" to something else (your choice), change the name of the .vi to something else and then use those two different subVIs in your program. You would need to repeat this for each subsequent event of the same type you wish to have.
  • Make an array of all the devices you intend to use with the event, and feed the array into a single EventCreate vi, and use a single EventExe handler for all the events. When using this method, it might be tempting to add multiple event handlers, but keep in mind that events only occur once, in whichever handler sees them first. When running multiple Phidgets through the single event handler, you can determine which one caused the event by comparing the phid terminal from the EventExe VI to the Phidget IDs (Device In/Device Out) of your Phidgets.

We recommend using either of the the first two solutions where possible. The first is a bit cleaner, but the second will work just as well. We only recommend using the third method in cases where it is not practical to manually create individual event handlers.

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