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Notice: This page contains information for the legacy Phidget21 Library.

Phidget21 is out of support. Bugfixes may be considered on a case by case basis.

Phidget21 does not support VINT Phidgets, or new USB Phidgets released after 2020. We maintain a selection of legacy devices for sale that are supported in Phidget21.

We recommend that new projects be developed against the Phidget22 Library.


Click on the 2phidget22.jpg button in the menu bar to go to the Phidget22 version of this page.

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Software Overview: Difference between revisions

From Phidgets Legacy Support
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   Loop waiting for events and user input:  
   Loop waiting for events and user input:  
</source><source lang=text style="color:red;">
</source><pre style="color:red;">
<span style="color:red;"> Change this loop to your input</span>
Change this loop to your input
</source><source lang=text>
</pre><source lang=text>
     If device attached: Get and Print various device statuses on request by input
     If device attached: Get and Print various device statuses on request by input
     Handle on-going attach and detach events
     Handle on-going attach and detach events

Revision as of 15:16, 2 November 2011

Operating System Support

Phidgets can run directly on these operating systems:

Phidgets can be driven remotely by these operating systems:

Language Support

Phidgets can be programmed either by an event-driven model, or by traditional linear code. All languages below support linear code. Some languages support our complete API, which includes support for event-driven design.

If you are flexible on what language you can use, we suggest choosing a language which supports event-driven code.

Phidgets have libraries to support Event Driven Code in the following languages:

Phidgets have libraries to support only Linear Code in the following languages:

Different Code Styles

User and device actions can be handled by either:

  • Letting the program tell you when they happen and then doing something (event driven code)
  • Waiting for them on your own and then and then doing something (linear code)

These styles can mix. For example, you can take a defined set of steps at first such as turning on an LED or antenna (linear code) and then doing nothing until an output change event is fired (event code).

With languages that support both styles, you can mix and match. For languages that support only linear code (see the Language Support Categories above) you can only use the linear style.

Examples in pseudo-code are given below for each style type so you can see how your language choice can affect your code design.

Event Driven Code

Event driven code

  // --- Event Functions ---

  Create any Language-Specific Functions

  Create General Attach, Detach, and Error Handling Functions
    On attach: Initialize hardware (antennas, etc)
    On detach: Reset any state variables

  Create Hardware-Specific Functions
    Print messages to notify they are called
    Perform minor accompanying changes (turn on LED, etc)

  // --- Main Code ---

  Create Device Software Object
  Attach Event Functions created above to Device
  Open Device

  Loop waiting for events and user input:
    If device attached: Get and Print various device statuses on request by input
    Handle on-going attach and detach events
    Exit upon specific user input

  Close Device
  Delete Device

Then, to add your own functionality, you might make the following changes:

  // --- Event Functions ---

  Create any Language-Specific Functions

  Create General Attach, Detach, and Error Handling Functions
    On attach: Initialize hardware (antennas, etc)
    On detach: Reset any state variables

  Create Hardware-Specific Functions
    Print messages to notify they are called
    Perform minor accompanying changes (turn on LED, etc)

  // --- Main Code ---

  Create Device Software Object
  Attach Event Functions created above to Device
  Open Device

  Loop waiting for events and user input:
Change this loop to your input
    If device attached: Get and Print various device statuses on request by input
    Handle on-going attach and detach events
    Exit upon specific user input

  Close Device
  Delete Device

Linear Code

Linear code

  Create Device Software Object
  Open Device
  Wait for Device Attachment
  Initialize any hardware (antennas, etc)

  Loop waiting for requests from user input:
    Get and Print various device statuses on request by input
    Exit upon specific user input

  Close Device
  Delete Device