Language - C: Difference between revisions

From Phidgets Support
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===Follow The Examples===
===Follow The Examples===


{{ExamplePseudocode|In C/C++ on Linux or Mac, you can name these '''event''' functions whatever you like.  They are then passed as function pointers to the Phidget library, which hooks them into the actual events when they occur. <br>  
{{ExamplePseudocode|In C/C++ on Linux or Mac, 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, they are called things like '''AttachHandler()''' and '''DetachHandler()'''.<br><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.
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.
In addition, functions in the examples like '''DeviceInitialize()''' will show what needs to be set up for your Phidget before using it.|HelloCreating a Phidget software object in C is specific to the Phidget.  For a Phidget Spatial, for example, this would involve:
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 C is specific to the Phidget.  For a Phidget Spatial, for example, this would involve creating an object with the <code>CPhidgetSpatialHandle</code> type, and then initializing it using the <code>CPhidgetSpatial_create</code> function.<br><br>
Other C calls follow a similar syntax, of <code>CPhidgetXXX_function</code>, where XXX is the name of your device, and function is an action available from the API for your specific Phidget.
}}
}}
Creating a Phidget software object in C is specific to the Phidget.  For a Phidget Spatial, for example, this would involve:<br>
CPhidgetSpatialHandle device = 0;
<br>
CPhidgetSpatial_create(&device));


==Write Your Own Code (Mac OSX/Linux)==
==Write Your Own Code (Mac OSX/Linux)==

Revision as of 22:37, 8 December 2011

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Support

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Quick Downloads

Just need the C/C++ drivers, libraries, and examples? Here they are:

C/C++ API Documentation:

C/C++ Example Code:

Libraries and Drivers:

Getting Started (Windows)

Run The Examples

A good way to learn to use Phidgets is to run and modify existing examples. You can find the C/C++ API and example code here:

To run the example code, you'll need to find the source code for your specific device within the example package. Then, compile the code under your platform and run it. 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

The Phidget examples were written using Visual C++ 2005. They also work well in other, similar environments such as Visual Studio.

Specific setup for many other compilers is covered below. Often, you can just import the example as an existing project, but if you are having trouble it might help to read the Write Your Own Code section below for your specific compiler.

Follow The Examples

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Write Your Own Code (Windows)

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General Windows Library Setup

In addition to actually creating code to drive your Phidget, you will also need to properly link the Phidget C/C++ libraries, which are included with the drivers above. Most compilers provide their own documentation on how to link external libraries. (Note that for Borland, you'll need a different library, which you can find in the Borland section below).

Then, in your code, you usually need to include the Phidget library specifically:

  #include "phidget21.h"

Visual C++ 2005 Library Setup

To link libraries in Visual C++ 2005:

  • Generate a new C/C++ console project with a descriptive name such as PhidgetTest.
  • Copy phidget21.h and phidget21.lib from the VC/VC++/Borland examples and add them to your project directory.
  • Open the project properties window.
  • Navigate to Configuration Properties | Linker | Input.
  • Edit the additional dependencies and add “phidget21.lib”.

The project now has access to the Phidget21 function calls and you are ready to begin coding.

Borland C/C++ Library Setup

To link libraries in Borland C/C++:

Make sure to download the additional Borland-specific libraries in addition to the drivers you already have through the Getting Started page for your device:

Create and Build Your Project

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With the libraries linked properly in your compiler, you can consult the following resources for help with writing code:

Build and compile your project with the properly linked libraries as you would any project on your specific compiler.

Getting Started (MacOS/Linux)

Run The Examples

One good way to start developing your application is to run and modify existing examples. You can find the C/C++ API and example code here:

To run the example code, you'll need to find the source code for your specific device. Then, compile the code under your platform and run it. 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

The examples assume that the compiled libraries have been set up properly.

  • To set them up on Mac OSX, follow the Getting Started page for your specific device
  • To set them up on Linux, compile and install them as explained on the main Linux page

Compiling and linking against the Phidgets Library for the example code can be done in the following ways:

To build on Linux:

  gcc example.c -o example -lphidget21

To build on MacOS (for example, depending on the Headers location):

  gcc example.c -o example -framework Phidget21 -I/Library/Frameworks/Phidget21.framework/Headers

After using gcc, you will have an executable named example that you can run.

Follow The Examples

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Write Your Own Code (Mac OSX/Linux)

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General Mac OS/Linux Library Setup

Before you can use the Phidget, you must include a reference to the library header.

  #include <phidget21.h>

Create and Build Your Project

With the libraries linked properly in your compiler, you can consult the following resources for help with writing code:


Compiling and linking against the Phidgets Library can be done in the following ways:

To build on Linux:

  gcc example.c -o example -lphidget21

To build on MacOS (for example, depending on the Headers location):

  gcc example.c -o example -framework Phidget21 -I/Library/Frameworks/Phidget21.framework/Headers

Development Environments and Compilers

Describe each major compiler and notable differences or important information. (eg. framework versions) If there are known issues/workarounds mention them and link to the corresponding issue at the bottom of the page.

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Common Problems and Solutions/Workarounds

Here you can put various frequent problems and our recommended solutions.