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<metadesc>Communicate over USB with sensors, controllers and relays with Phidgets! Our C library supports Windows/MacOS/Linux using Visual Studio or GCC.</metadesc>
{{#seo:|description=Learn how to use Phidget USB devices with C and C++.}}
[[Category:Language]]
[[Category:Language]]
__TOC__


== Quick Downloads ==
== Get Started ==
With the Phidget22 library, it's easy to create C or C++ applications that work with Phidget devices.


=== Documentation ===
== C Libraries ==
If you've installed the Phidget drivers for [[OS - Windows|Windows]], [[OS - macOS|MacOS]], or [[OS - Linux|Linux]], then you already have the files you need for your C project.


*{{Phidget22API}} (select C from the drop-down menu)
==== Windows Considerations ====
When adding directories for your project dependencies, add
<syntaxhighlight>
C:/Program Files/Phidgets/Phidget22
</syntaxhighlight>
And for the linker, you can add
<syntaxhighlight>
C:/Program Files/Phidgets/Phidget22/phidget22.lib}}     #(for 64-bit systems)
C:/Program Files/Phidgets/Phidget22/x86/phidget22.lib}} #(for 32-bit systems)
</syntaxhighlight>


=== Example Code ===
==== MacOS Considerations ====
 
The Phidget framework will be found in
*{{SampleCode|C|C Examples}}
<syntaxhighlight>
 
/Library/Frameworks
===Libraries===
</syntaxhighlight>
 
And the headers can be found in  
{{AllQuickDownloads}}
<syntaxhighlight>
 
/Library/Frameworks/Phidget22.framework/Headers
== Getting Started with C ==
Welcome to using Phidgets with C! By using C, you will have access to the complete Phidget22 API, including events. Example code is also provided for each Phidget channel class.
 
If developing for Windows, keep reading; otherwise, select an operating system:
*[[#macOS | macOS]]
*[[#Linux | Linux]]
 
== Windows ==
===Install Phidget Drivers for Windows===
Before getting started with the guides below, ensure you have the following components installed on your machine:
 
# You will need the [[OS_-_Windows#Quick_Downloads|Phidgets Windows Drivers]]
 
===Visual Studio===
====Use Our Examples====
One of the best ways to start programming with Phidgets is to use our example code as a guide. In order to run the examples, you will need to download and install [https://www.visualstudio.com/ Microsoft Visual Studio].
 
 
Now that you have Microsoft Visual Studio installed, select an example that will work with your Phidget:
*{{SampleCode|C|C Examples}}
 
 
Open the example project and start the example by pressing the ''Local Windows Debugger'' button:
 
 
[[Image: c_vs_run.png|link=|center]]
 
 
The application will open the Phidget, list basic information about the Phidget, and demonstrate the Phidget's functionality. Here is an example of an Accelerometer channel on a Spatial Phidget:
 
 
[[Image: c_vs_output.PNG|link=|center]]
 
{{Edit_the_Examples}}
 
====Setting up a New Project====
When you are building a project from scratch, or adding Phidget functionality to an existing project, you'll need to configure your development environment to properly link the Phidget C library. To begin:
 
 
Create a new Win32 Console application:
 
[[Image:C_vs_newproject.PNG|link=|center]]
 
 
Select an empty project and finish:
 
[[Image:C_vs_emptyproject.PNG|link=|center]]
 
 
If you are using a 64-bit machine, select x64, otherwise, keep x86:
 
[[Image:C_vs_configuration.png|link=|center]]
 
 
Next, add a new item to your source folder:
 
[[Image:C_vs_additem.png|link=|center]]
 
 
Give the source file a descriptive name and continue:
 
[[Image:C_vs_addsource.PNG|link=|center]]
 
 
Access the project's properties:
 
[[Image:C_vs_propertie.png|link=|center]]
 
 
Next, navigate to Configuration Properties -> C/C++ -> General and add the following line to the additional include directories:
*C:\Program Files\Phidgets\Phidget22
 
 
[[Image:C_vs_additionalinclude.png|link=|center]]
 
 
Navigate to Configuration Properties -> Linker -> Input and add the following line to the additional dependencies:
*C:\Program Files\Phidgets\Phidget22\phidget22.lib
 
 
[[Image:C_vs_additionadepend.png|link=|center]]
 
Finally, include the Phidget library in your code, and any other header files:
 
<syntaxhighlight lang='C'>
#include <phidget22.h>
</syntaxhighlight>
</syntaxhighlight>


[[Image:C_vs_finished.PNG|link=|center]]
====Linux Considerations====
Linux restricts access to USB devices to the root user.  


To run your C application as a regular user, you'll need to [{{SERVER}}/docs/OS_-_Linux#Setting_udev_Rules set up udev rules] on your system.


Success! The project now has access to Phidgets. Next, view the [[#Write Code | write your own code]] section located below.
=== Library Files ===
If you would like to manually manage the Phidget22 library files, you can download them [https://cdn.phidgets.com/downloads/phidget22/libraries/windows/Phidget22-windevel.zip here].


===GCC===
== Development Environment Configuration ==
====Cygwin/MinGW====
=====Use Our Examples=====
One of the best ways to start programming with Phidgets is to use our example code as a guide. In order to run the examples, you will need to download and install either [http://www.mingw.org/ MinGW] or [https://www.cygwin.com/ Cygwin].


=== GCC ===
{| style="margin:auto;" class="table-no-border mw-collapsible mw-collapsed"
|+ '''Instructions'''
|
The most common tool for C development is GCC, whether used in the command line or through an IDE. GCC is packaged with many other IDEs and packages, so you may already have it installed.


Now that you have either MinGW or Cygwin installed, select an example that will work with your Phidget:
{{hiddenh4|Windows}}
*{{SampleCode|C|C Examples}}
We recommend installing [https://www.cygwin.com/ Cygwin] or [https://sourceforge.net/projects/mingw/ MinGW], ensuring you select all gcc packages when prompted by the installer. 


To compile your code, go to the folder where your code is and open the command prompt by typing 'cmd' in the address bar.


If you are using Cygwin, navigate to the folder where the example is and open the command prompt. Enter the following command to compile the example:
The specific command you will use depends on your compiler of choice:
<syntaxhighlight lang='bash'>
<syntaxhighlight lang=bash>
gcc example.c -o example -I"/cygdrive/c/Program Files/Phidgets/Phidget22" -L"/cygdrive/c/Program Files/Phidgets/Phidget22/x86" -lphidget22
#Cygwin x86:
</syntaxhighlight>
gcc example.c -o example -I"/cygdrive/c/Program Files/Phidgets/Phidget22"-L"/cygdrive/c/Program Files/Phidgets/Phidget22/x86" -lphidget22


#Cygwin x64:
gcc example.c -o example -I"/cygdrive/c/Program Files/Phidgets/Phidget22" -L"/cygdrive/c/Program Files/Phidgets/Phidget22" -lphidget22


If you are using MinGW, navigate to the folder where the example is and open the command prompt. Enter the following command to compile the example:
#MinGW:
<syntaxhighlight lang='bash'>
gcc example.c -o example -I"C:/Program Files/Phidgets/Phidget22" -L"C:/Program Files/Phidgets/Phidget22/x86" -lphidget22
gcc example.c -o example -I"C:/Program Files/Phidgets/Phidget22" -L"C:/Program Files/Phidgets/Phidget22/x86" -lphidget22
</syntaxhighlight>
</syntaxhighlight>


After running the commands above for either Cygwin or MinGW, an executable file called ''example.exe'' will be created. Enter the following command to run the example:
After running the commands above for either Cygwin or MinGW, an executable file called example.exe will be created. Enter the following command to run the program:
<syntaxhighlight lang='bash'>
<syntaxhighlight lang=bash>
example.exe
example.exe
</syntaxhighlight>
</syntaxhighlight>
{{hiddenh4|MacOS}}
If you don't already have gcc installed, you can get it by installing [https://developer.apple.com/xcode/ Xcode].


{{Edit_the_Examples}}
To compile the program, enter the following command in the terminal, substituting "example" for the name of your C file:
 
<syntaxhighlight lang=bash>
====Setting up a New Project====
When you are building a project from scratch, or adding Phidget functionality to an existing project, you'll need to configure your development environment to properly link the Phidget C library.
 
To include the Phidget C library, add the following line to your code:
<syntaxhighlight lang='C'>
#include <phidget22.h>
</syntaxhighlight>
 
You can now compile the file as shown in the previous section.
 
 
The project now has access to Phidgets. Next, view the [[#Write Code | write your own code]] section located below.
 
===Code::Blocks===
====Use Our Examples====
One of the best ways to start programming with Phidgets is to use our example code as a guide. In order to run the examples, you will need to download and install [http://www.codeblocks.org/downloads Code::Blocks].
 
 
Now that you have Code::Blocks installed, select an example that will work with your Phidget:
*{{SampleCode|C|C Examples}}
 
 
Open the example in Code::Blocks (you do not need to create a new project) and navigate to Settings -> Compiler... as shown in the image below:
 
[[Image:C_codeblocks_settings.png|link=|center]]
 
 
From the Global compiler settings screen, navigate to Search directories -> Compiler and add the following directory:
*C:\Program Files\Phidgets\Phidget22
 
[[Image:C_codeblocks_compiler.PNG|link=|center]]
 
 
Next, select Search directories -> Linker and add the following directory:
*C:\Program Files\Phidgets\Phidget22\x86
 
[[Image:C_codeblocks_linker.PNG|link=|center]]
 
 
Finally, from the Global compiler settings screen, navigate to Linker settings and add the following line:
*phidget22
 
[[Image:C_codeblocks_libraries.PNG|link=|center]]
 
 
You can now build and run the example:
 
[[Image:C_codeblocks_run.png|link=|center]]
 
{{Edit_the_Examples}}
 
====Setting up a New Project====
When you are building a project from scratch, or adding Phidget functionality to an existing project, you'll need to configure your development environment to properly link the Phidget C library.
 
 
To include the Phidget C library, add the following line to your code:
<syntaxhighlight lang='C'>
#include <phidget22.h>
</syntaxhighlight>
 
You can now compile the file as shown in the previous section.
 
 
The project now has access to Phidgets. Next, view the [[#Write Code | write your own code]] section located below.
 
==macOS==
===Install Phidget Drivers for macOS===
Before getting started with the guides below, ensure you have the following components installed on your machine:
 
# You will need the [[OS_-_macOS#Quick_Downloads|Phidgets macOS Drivers]]
 
===GCC===
====Use Our Examples====
One of the best ways to start programming with Phidgets is to use our example code as a guide. You likely have gcc installed on your macOS machine already, but if not, you can easily get it by downloading [https://developer.apple.com/xcode/ Xcode].
 
Next, select an example that will work with your Phidget:
*{{SampleCode|C|C Examples}}
 
 
To compile the example program, enter the following command in the terminal:
<syntaxhighlight lang='bash'>
gcc example.c -o example -F /Library/Frameworks -framework Phidget22 -I /Library/Frameworks/Phidget22.framework/Headers
gcc example.c -o example -F /Library/Frameworks -framework Phidget22 -I /Library/Frameworks/Phidget22.framework/Headers
</syntaxhighlight>
</syntaxhighlight>
Finally, run the program by entering the following command in the terminal:
Finally, run the program by entering the following command in the terminal:
<syntaxhighlight lang='bash'>
<syntaxhighlight lang=bash>
./example
./example
</syntaxhighlight>
</syntaxhighlight>
Success! The project is now running with Phidgets.


 
{{hiddenh4|Linux}}
[[Image:c_mac_gcc.png|link=|center]]
On Linux, gcc is installed through the package manager:
 
<syntaxhighlight lang=bash>
 
{{Edit_the_Examples}}
 
====Setting up a New Project====
When you are building a project from scratch, or adding Phidget functionality to an exisiting project, you'll need to configure your development environment to properly link the Phidget C library.
 
To include the Phidget C library, simply add the following line to your code:
<syntaxhighlight lang='C'>
#include <phidget22.h>
</syntaxhighlight>
 
You can now compile the file as shown in the previous section.
 
 
The project now has access to Phidgets. Next, view the [[#Write Code | write your own code]] section located below.
 
==Linux==
===Install Phidget Drivers for Linux===
Before getting started with the guides below, ensure you have the following components installed on your machine:
 
# You will need the [[OS_-_Linux#Quick_Downloads|Phidgets Linux Drivers]]
 
===GCC===
====Use Our Examples====
One of the best ways to start programming with Phidgets is to use our example code as a guide. You likely have gcc installed on your Linux machine already, but if not, you can easily get it by entering the following command in the terminal:
<syntaxhighlight lang='C'>
apt-get install gcc
apt-get install gcc
</syntaxhighlight>
</syntaxhighlight>
 
To compile the program, enter the following command in the terminal, substituting "example" for the name of your C file:
 
<syntaxhighlight lang=bash>
Next, select an example that will work with your Phidget:
*{{SampleCode|C|C Examples}}
 
 
To compile the example, enter the following command in the terminal:
 
<syntaxhighlight lang='bash'>
gcc example.c -o example -lphidget22
gcc example.c -o example -lphidget22
</syntaxhighlight>
</syntaxhighlight>
After compiling, you can run the program by entering the following command in the terminal:
After compiling, you can run the program by entering the following command in the terminal:
<syntaxhighlight lang='bash'>
<syntaxhighlight lang=bash>
./example
./example
</syntaxhighlight>
</syntaxhighlight>
Success! The project is now running with Phidgets.
|-
|}


 
=== Visual Studio ===  
{{Edit_the_Examples}}
{| style="margin:auto;" class="table-no-border mw-collapsible mw-collapsed"
 
|+ '''Instructions'''
====Setting up a New Project====
| If you want to jump right into a pre-configured project, you can download one on our [https://www.phidgets.com/?view=code_samples&lang=C Code Sample Generator] page. || [[Image:Language_C_VSProject.jpg|center|link=https://cdn.phidgets.com/docs/images/f/f1/Language_C_VSProject.jpg|350px]]
When you are building a project from scratch, or adding Phidget functionality to an exisiting project, you'll need to configure your development environment to properly link the Phidget C library.
|-
 
| To configure a new project, follow these steps. ||
To include the Phidget C library, simply add the following line to your code:
|-
<syntaxhighlight lang='C'>
| First, create a new Win32 Console Application: || [[Image:Language_C_VS_step1.jpg|center|link=https://cdn.phidgets.com/docs/images/a/a1/Language_C_VS_step1.jpg|350px]]
#include <phidget22.h>
|-
</syntaxhighlight>
| If you are using a 64-bit machine, select x64, otherwise, select x86: || [[Image:Language_C_VS_step2.jpg|center|link=https://cdn.phidgets.com/docs/images/6/6b/Language_C_VS_step2.jpg|350px]]
 
|-
You can now compile the file as shown in the previous section.
| Next, right click on the source folder and click New Item: || [[Image:Language_C_VS_step3.jpg|center|link=https://cdn.phidgets.com/docs/images/e/e1/Language_C_VS_step3.jpg|350px]]
 
|-
 
| Give the source file a name and click Add: || [[Image:Language_C_VS_step4.jpg|center|link=https://cdn.phidgets.com/docs/images/e/e5/Language_C_VS_step4.jpg|350px]]
The project now has access to Phidgets. Next, view the [[#Write Code | write your own code]] section located below.
|-
 
| Right click your project and access its properties: || [[Image:Language_C_VS_step5.jpg|center|link=https://cdn.phidgets.com/docs/images/1/1e/Language_C_VS_step5.jpg|350px]]
== Editing the Examples==
|-
To get our example code to run in a custom application, simply remove the calls to ''AskForDeviceParameters'' and ''PrintEventDescriptions'', and hard-code the addressing parameters for your application.
| Go to Configuration Properties -> C/C++ -> General and add this to the additional include directories:
 
<syntaxhighlight>
If you are unsure what values to use for the addressing parameters, check the [[Finding The Addressing Information]] page.
C:\Program Files\Phidgets\Phidget22
 
For instance:
<syntaxhighlight lang=C>
AskForDeviceParameters(&channelInfo, (PhidgetHandle)ch);
 
prc = Phidget_setDeviceSerialNumber((PhidgetHandle)ch, channelInfo.deviceSerialNumber);
CheckError(prc, "Setting DeviceSerialNumber", &(PhidgetHandle)ch);
 
prc = Phidget_setHubPort((PhidgetHandle)ch, channelInfo.hubPort);
CheckError(prc, "Setting HubPort", &(PhidgetHandle)ch);
 
prc = Phidget_setIsHubPortDevice((PhidgetHandle)ch, channelInfo.isHubPortDevice);
CheckError(prc, "Setting IsHubPortDevice", &(PhidgetHandle)ch);
   
Phidget_setChannel((PhidgetHandle)ch, channelInfo.channel);
CheckError(prc, "Setting Channel", &(PhidgetHandle)ch);
 
if (channelInfo.netInfo.isRemote) {
    prc = Phidget_setIsRemote((PhidgetHandle)ch, channelInfo.netInfo.isRemote);
    CheckError(prc, "Setting IsRemote", &(PhidgetHandle)ch);
       
    if (channelInfo.netInfo.serverDiscovery) {
        prc = PhidgetNet_enableServerDiscovery(PHIDGETSERVER_DEVICEREMOTE);
        CheckEnableServerDiscoveryError(prc, &(PhidgetHandle)ch);
    } else {
        prc = PhidgetNet_addServer("Server", channelInfo.netInfo.hostname,
                    channelInfo.netInfo.port, channelInfo.netInfo.password, 0);
        CheckError(prc, "Adding Server", &(PhidgetHandle)ch);
    }
}
</syntaxhighlight>
 
Might become:
 
<syntaxhighlight lang=C>
prc = Phidget_setDeviceSerialNumber((PhidgetHandle)ch, 370114);
CheckError(prc, "Setting DeviceSerialNumber", &(PhidgetHandle)ch);
 
prc = Phidget_setHubPort((PhidgetHandle)ch, 2);
CheckError(prc, "Setting HubPort", &(PhidgetHandle)ch);
 
prc = Phidget_setIsHubPortDevice((PhidgetHandle)ch, 1);
CheckError(prc, "Setting IsHubPortDevice", &(PhidgetHandle)ch);
</syntaxhighlight>
 
Notice that you can leave out any parameter not relevant to your application for simplicity.
 
You can then manipulate the rest of the code as your application requires. A more in-depth description of programming with Phidgets follows in the [[#Write Code| Write Code]] section.
 
==Write Code==
{{WriteCode_Intro|C}}
 
=== Step One: Create and Address===
You will need to create your Phidget object in your code. For example, we can create a digital input object like this:
<syntaxhighlight lang=c>
PhidgetDigitalInputHandle ch;
PhidgetDigitalInput_create(&ch);
</syntaxhighlight>
 
Next, we can address which Phidget we want to connect to by setting parameters such as ''DeviceSerialNumber''.
 
<syntaxhighlight lang=C>
Phidget_setDeviceSerialNumber((PhidgetHandle)ch, 496911);
</syntaxhighlight>
 
Although we are not including it on this page, you should handle the return codes of all Phidget functions. Here is an example of the previous code with error handling:
<syntaxhighlight lang=C>
PhidgetReturnCode prc;
PhidgetDigitalInputHandle ch;
 
prc = PhidgetDigitalInput_create(&ch);
if (prc != EPHIDGET_OK) {
fprintf(stderr, "Runtime Error -> Creating DigitalInput: \n\t");
fprintf(stderr, "Code: 0x%x\n", error);
return 1;
}
 
prc = Phidget_setDeviceSerialNumber((PhidgetHandle)ch, 496911);
if (prc != EPHIDGET_OK) {
fprintf(stderr, "Runtime Error -> Setting DeviceSerialNumber: \n\t");
fprintf(stderr, "Code: 0x%x\n", error);
return 1;
}
</syntaxhighlight>
 
=== Step Two: Open and Wait for Attachment===
 
After we have specified which Phidget to connect to, we can open the Phidget object like this:
<syntaxhighlight lang=C>
Phidget_openWaitForAttachment((PhidgetHandle)ch, 5000);
</syntaxhighlight>
</syntaxhighlight>
 
|| [[Image:Language_C_VS_step6.jpg|center|link=https://cdn.phidgets.com/docs/images/d/d3/Language_C_VS_step6.jpg|350px]]
To use a Phidget, it must be plugged in (attached). We can handle this by calling ''openWaitForAttachment'', which will block indefinitely until a connection is made, or until the timeout value is exceeded. Simply calling ''open'' does not guarantee you can use the Phidget immediately.
|-
 
| Go to Configuration Properties -> Linker -> Input and add the appropriate line to additional dependencies:
Alternately, you could verify the device is attached by using event driven programming and tracking the attach events.
<syntaxhighlight>
 
C:\Program Files\Phidgets\Phidget22\phidget22.lib #(for 64-bit systems)
To use events to handle attachments, we have to modify our code slightly:
C:\Program Files\Phidgets\Phidget22\x86\phidget22.lib #(for 32-bit systems)
<syntaxhighlight lang=C>
PhidgetDigitalInputHandle ch;
PhidgetDigitalInput_create(&ch);
 
Phidget_setOnAttachHandler((PhidgetHandle)ch, onAttachHandler, null);
 
Phidget_openWaitForAttachment((PhidgetHandle)ch, 5000);
</syntaxhighlight>
</syntaxhighlight>
 
|| [[Image:Language_C_VS_step7.jpg|center|link=https://cdn.phidgets.com/docs/images/0/09/Language_C_VS_step7.jpg|350px]]
Next, we have to declare the function that will be called when an attach event is fired - in this case the function ''onAttachHandler'' will be called:
|-
<syntaxhighlight lang=C>
| Lastly, include the Phidget library at the beginning of your program:
static void CCONV onAttachHandler(PhidgetHandle ph, void *ctx) {
<syntaxhighlight lang=bash>
    printf("Phidget attached!\n");
#include < phidget22.h >
}
</syntaxhighlight>
</syntaxhighlight>
||
|-
|}


We recommend using this attach handler to set any initialization parameters for the channel such as DataInterval and ChangeTrigger from within the AttachHandler, so the parameters are set as soon as the device becomes available.
=== PhidgetSBC Web Interface ===
 
{| style="margin:auto;" class="table-no-border mw-collapsible mw-collapsed"
=== Step Three: Do Things with the Phidget ===
|+'''Instructions'''
We recommend the use of event driven programming when working with Phidgets. In a similar way to handling an attach event as described above, we can also add an event handler for a state change event:
|<center>{{#ev:youtube|2hTlVexctqY|rel=0}}</center>  
<syntaxhighlight lang=C>
|}
PhidgetDigitalInputHandle ch;
PhidgetDigitalInput_create(&ch);
 
Phidget_setOnAttachHandler((PhidgetHandle)ch, onAttachHandler, null);
PhidgetDigitalInput_setOnStateChangeHandler(ch, onStateChangeHandler, null);
 
Phidget_openWaitForAttachment((PhidgetHandle)ch, 5000);
</syntaxhighlight>
 
This code will connect a function to an event. In this case, the ''onStateChangeHandler'' function will be called when there has been a change to the channel's input. Next, we need to create the ''onStateChangeHandler'' function:
<syntaxhighlight lang=C>
static void CCONV onStateChangeHandler(PhidgetDigitalInputHandle ph, void *ctx, int state) {
    printf("State: %d\n", state);
}
</syntaxhighlight>
 
If you are using multiple Phidgets in your program, check out our page on [[Using_Multiple_Phidgets]] for information on how to properly address them and use them in events.
 
If events do not suit your needs, you can also poll the device directly for data using code like this:
<syntaxhighlight lang=C>
int state;
PhidgetDigitalInput_getState(ch, &state);
printf("State: %d\n", state);
</syntaxhighlight>
 
'''Important Note:''' There will be a period of time between the attachment of a Phidget sensor and the availability of the first data from the device. Any attempts to get this data before it is ready will result in an error code, and a specific nonsensical result. See more information on this on our page for [[Unknown Values]].
 
====Enumerations====
 
Some Phidget devices have functions that deal with specific predefined values called enumerations. Enumerations commonly provide readable names to a set of numbered options.
 
Enumerations with Phidgets in C will take the form of '''ENUMERATION_NAME'''.
 
For example, specifying a SensorType to use the 1142 for a voltage input would look like:
<syntaxhighlight lang=C>
SENSOR_TYPE_1142
</syntaxhighlight>
and specifying a K-Type thermocouple for a temperature sensor would be:
<syntaxhighlight lang=C>
THERMOCOUPLE_TYPE_K
</syntaxhighlight>
The Phidget error code for timing out could be specified as:
<syntaxhighlight lang=C>
EPHIDGET_TIMEOUT
</syntaxhighlight>
 
You can find the Enumeration Type under the ''Enumerations'' section of the {{Phidget22API}} for your device, and the Enumeration Name in the drop-down list within.
 
=== Step Four: Close and Delete ===
At the end of your program, be sure to close and delete your device:
<syntaxhighlight lang=C>
Phidget_close((PhidgetHandle)ch);
PhidgetDigitalInput_delete(&ch);
</syntaxhighlight>
 
== Further Reading ==
 
[[Phidget Programming Basics]] - Here you can find the basic concepts to help you get started with making your own programs that use Phidgets.
 
[[Data Interval/Change Trigger]] - Learn about these two properties that control how much data comes in from your sensors.


[[Using Multiple Phidgets]] - It can be difficult to figure out how to use more than one Phidget in your program. This page will guide you through the steps.
== Example Code ==
Navigate to our [https://www.phidgets.com/?view=code_samples&lang=C Code Sample Generator] to view and download code samples that are tailored to your specific device.


[[Polling vs. Events]] - Your program can gather data in either a polling-driven or event-driven manner. Learn the difference to determine which is best for your application.
[[Image:Language_c_codesample2.png|center|600px|link=]]


[[Logging, Exceptions, and Errors]] - Learn about all the tools you can use to debug your program.
===Phidget Programming Basics===
{{PhidgetProgrammingBasicsLink}}


[[Phidget Network Server]] - Phidgets can be controlled and communicated with over your network- either wirelessly or over ethernet.
==API==
[{{SERVER}}/?view=api&lang=C Phidget22 API]

Latest revision as of 20:03, 12 March 2026


Get Started

With the Phidget22 library, it's easy to create C or C++ applications that work with Phidget devices.

C Libraries

If you've installed the Phidget drivers for Windows, MacOS, or Linux, then you already have the files you need for your C project.

Windows Considerations

When adding directories for your project dependencies, add 

C:/Program Files/Phidgets/Phidget22

And for the linker, you can add 

C:/Program Files/Phidgets/Phidget22/phidget22.lib}}     #(for 64-bit systems)
C:/Program Files/Phidgets/Phidget22/x86/phidget22.lib}} #(for 32-bit systems)

MacOS Considerations

The Phidget framework will be found in 

/Library/Frameworks

And the headers can be found in 

/Library/Frameworks/Phidget22.framework/Headers

Linux Considerations

Linux restricts access to USB devices to the root user.

To run your C application as a regular user, you'll need to set up udev rules on your system.

Library Files

If you would like to manually manage the Phidget22 library files, you can download them here.

Development Environment Configuration

GCC

Instructions

The most common tool for C development is GCC, whether used in the command line or through an IDE. GCC is packaged with many other IDEs and packages, so you may already have it installed.

Windows

We recommend installing Cygwin or MinGW, ensuring you select all gcc packages when prompted by the installer.

To compile your code, go to the folder where your code is and open the command prompt by typing 'cmd' in the address bar.

The specific command you will use depends on your compiler of choice: 

#Cygwin x86:
gcc example.c -o example -I"/cygdrive/c/Program Files/Phidgets/Phidget22"-L"/cygdrive/c/Program Files/Phidgets/Phidget22/x86" -lphidget22

#Cygwin x64:
gcc example.c -o example -I"/cygdrive/c/Program Files/Phidgets/Phidget22" -L"/cygdrive/c/Program Files/Phidgets/Phidget22" -lphidget22

#MinGW:
gcc example.c -o example -I"C:/Program Files/Phidgets/Phidget22" -L"C:/Program Files/Phidgets/Phidget22/x86" -lphidget22

After running the commands above for either Cygwin or MinGW, an executable file called example.exe will be created. Enter the following command to run the program: 

example.exe
MacOS

If you don't already have gcc installed, you can get it by installing Xcode.

To compile the program, enter the following command in the terminal, substituting "example" for the name of your C file: 

gcc example.c -o example -F /Library/Frameworks -framework Phidget22 -I /Library/Frameworks/Phidget22.framework/Headers

Finally, run the program by entering the following command in the terminal: 

./example

Success! The project is now running with Phidgets.

Linux

On Linux, gcc is installed through the package manager: 

apt-get install gcc

To compile the program, enter the following command in the terminal, substituting "example" for the name of your C file: 

gcc example.c -o example -lphidget22

After compiling, you can run the program by entering the following command in the terminal: 

./example

Success! The project is now running with Phidgets.

Visual Studio

Instructions
If you want to jump right into a pre-configured project, you can download one on our Code Sample Generator page.
Language C VSProject.jpg
To configure a new project, follow these steps.
First, create a new Win32 Console Application:
Language C VS step1.jpg
If you are using a 64-bit machine, select x64, otherwise, select x86:
Language C VS step2.jpg
Next, right click on the source folder and click New Item:
Language C VS step3.jpg
Give the source file a name and click Add:
Language C VS step4.jpg
Right click your project and access its properties:
Language C VS step5.jpg
Go to Configuration Properties -> C/C++ -> General and add this to the additional include directories: 
C:\Program Files\Phidgets\Phidget22
Language C VS step6.jpg
Go to Configuration Properties -> Linker -> Input and add the appropriate line to additional dependencies: 
C:\Program Files\Phidgets\Phidget22\phidget22.lib #(for 64-bit systems)
C:\Program Files\Phidgets\Phidget22\x86\phidget22.lib #(for 32-bit systems)
Language C VS step7.jpg
Lastly, include the Phidget library at the beginning of your program: 
#include < phidget22.h >

PhidgetSBC Web Interface

Instructions

Example Code

Navigate to our Code Sample Generator to view and download code samples that are tailored to your specific device.

Language c codesample2.png

Phidget Programming Basics

To learn more about the structure of the example code, visit our Phidget Programming Basics guide.

API

Phidget22 API

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