Language - C

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Revision as of 16:36, 22 December 2011 by 192.168.2.198 (talk) (→‎Dev C++)

Icon-C++.png C++ is a general purpose, cross-platform programming language with a vast user base.

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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 with C/C++

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

Instructions are divided up by operating system. Choose:

Windows

C/C++ programs on Windows depend on three files, which the installers above put onto your system:

  • Phidget21.dll contains the actual Phidgets library, which is used at run-time. If you used our installer, it's already correctly placed in C:\Windows\System32. It can be manually installed - check our Manual Installation instructions.
  • Phidget21.lib is used by your compiler to link to the dll. Your compiler has to know where this file is. Our installer puts Phidget21.lib into C:\Program Files\Phidgets. Phidget21.lib is written to be compatible with most compilers - but your specific compiler may need a different format. Check our documentation for your specific compiler below for details.
  • Phidget21.h lists all the Phidget API function calls available to your code. Your compiler also has to know where this file is. By default, our installer puts Phidget21.h 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. We offer some instruction below, by compiler.

To run the examples, you will download them and unpack them into a folder. If you browse around within the examples, you'll note that the examples are specific to each Phidget. So, you'll need to find the source code for your specific device within the example package.

When you are building a project from scratch, or adding Phidget function calls to an existing project, you'll need to configure your compiler / development environment to properly link the Phidget C/C++ libraries. Please check your compiler section below. Then, in your code, you will need to include the Phidget library: 

  #include <phidget21.h>

Visual Studio

Start by downloading the Visual C/C++ Examples. Our examples were written in Visual Studio 2005, but Visual Studio 2008 / 2010 will easily upgrade them.

C++/CLI (used to be called Managed C++) is very different from mainstream C/C++. If you are familiar in C++/CLI, consider calling the .NET library, instead of the C API normally used from C/C++. We have no documentation for using C++/CLI.

Microsoft makes free versions of Visual Studio available known as Express Editions. The Express editions are somewhat limited in functionality - in practice this does not seem to be a problem for most people.

Visual Studio 2010

From Visual Studio, to load all projects, go to File > Open > Project / Solution, and open "Visual Studio Phidgets Examples" in the VCpp folder of the examples. A wizard will open and convert the projects to VS2010 format.

Visual Studio 2008

From Visual Studio, to load all projects, go to File > Open > Project / Solution, and open "Visual Studio Phidgets Examples" in the VCpp folder of the examples. A wizard will open and convert the projects to VS2008 format.

Visual Studio 2005

From Visual Studio, to load all projects, go to File > Open > Project / Solution, and open "Visual Studio Phidgets Examples" in the VCpp folder of the examples.

To link libraries in Visual C++ 2005:

  • Generate a new C/C++ console project with a descriptive name such as PhidgetTest.
  • Open the project properties window.
  • Navigate to Configuration Properties | C/C++
  • Add "C:\Program Files\Phidgets" to the additional directories field.
  • Navigate to Configuration Properties | Linker | Input.
  • Edit the additional dependencies and add "C:\Program Files\Phidgets\phidget21.lib".

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

Visual Studio 2003

  • How would customer load our examples? Wizard does not work backwards, I assume.

Visual Studio 6

  • How would customer load our examples? Wizard does not work backwards, I assume.

Borland

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:

To compile and link your program: bcc32 -I"C:\Program Files\Phidgets" -L"C:\Program Files\Phidgets" phidget21bcc.lib example.c

GCC on Windows

Cygwin

To compile and link your program: gcc example.c -I"/cygdrive/c/Program Files/Phidgets" -L"/cygdrive/c/Program Files/Phidgets" -lphidget21

MinGW

To compile and link your program: gcc example.c -I"C:\Program Files\Phidgets" -L"C:\Program Files\Phidgets" -lphidget21

Dev C++

In order to control Phidgets with Dev-C++, the library file will need to be in a format that Dev-C++ accepts, as described in the following steps. The following steps works with Dev-C++ 4.9.9.2. Download the reimp tool(Please download it here), and type the following command to create libphidget21.a. 

reimp.exe "C:\Program Files\Phidgets\phidget21.lib"

Place libphidget21.a in <Dev-Cpp Install Directory>/lib

Open up your project in Dev-C++, and traverse to Project Options->Parameters->Linker, and enter the following to link to the library: 

-lphidget21

Next, the path to phidget21.h will need to be specified. Traverse to Project Options->Directories->Include Directories, and add the path to the Phidget installation directory: 

C:\Program Files\Phidgets

The 64 bit version of phidget21.lib is not supported on Dev C/C++. Please use the 32 bit version of phidget21.lib.

Mac OSX

C/C++ has excellent support on Mac OSX through the gcc compiler.

The first step in using C/C++ on Mac is to install the Phidget libraries. Compile and install them as explained on the getting started guide for your device. Then, the OS - Mac OSX page also describes the different Phidget files, their installed locations, and their roles.

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Use Our Examples

After installing the Phidget libraries for Linux as above, you're ready to run the examples:

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.

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 compile, link the Phidget libraries, and build an executable binary on MacOS, do (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.

Write Your Own Code

When writing your code from scratch, you must include a reference to the library header: 

  #include <phidget21.h>

Then, you would compile your completed C/C++ code the same way as the examples above.

To learn how to write your own code for your Phidget, and to learn more about our API, we have a teaching section to help you follow the provided C/C++ examples. Even more help and references are provided from there.

Linux

C/C++ has excellent support on Linux through the gcc compiler.

The first step in using C/C++ on Linux is to install the Phidget libraries. Compile and install them as explained on the main Linux page. That Linux page also describes the different Phidget files, their installed locations, and their roles.

Use Our Examples

After installing the Phidget libraries for Linux as above, you're ready to run the examples:

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.

To compile, link the Phidget libraries, and build a binary executable on Linux, do the following in a terminal in the directory with example.c: 

  gcc example.c -o example -lphidget21

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

On Linux, if you have not set up your udev rules for USB access, you will need to run the program as root.

Write Your Own Code

When writing your code from scratch, you must include a reference to the library header from within your .c source code file: 

  #include <phidget21.h>

Then, you would compile your completed C/C++ code the same way as the examples above.

To learn how to write your own code for your Phidget, and to learn more about our API, we have a teaching section to help you follow the provided C/C++ examples. Even more help and references are provided from there.

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.

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When changing the examples to do what you want, or writing your own code, you will probably find these API resources useful because they outline the C/C++ functions that you can use:

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Common Problems and Solutions/Workarounds

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

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