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[[Category:Language]]
[[Category:Language]]
{{OSLang|[[File:icon-Python.png|64x64px|link=|alt=Python]]|Python is an object oriented programming language developed by the [http://www.python.org/psf/summary/ Python Software Foundation], is powerful and easy to learn.}}
__NOTOC__
__TOC__


==Introduction==
We provide support for Python in all major operating systems. We also provide instructions on how to get your project started in a number of common development environments. Select your operating system and preferred development environment below, and follow the instructions to get your project running with Phidgets.


{{LanguageSupport|Python|the complete Phidget API, including events|all Phidget devices.|Windows, OS X and Linux. We provide instructions on how to set up your environment for [[#Command line | command line]], [[#IDLE | IDLE]], and [[#Eclipse with PyDev | Eclipse with PyDev]]|
If you do not know which development environment you want to use, or your development environment of choice is not listed, we recommend starting with command line or terminal as the simplest path to getting your code running.


Only Python 2.5 or higher is supported.}}
Once you have set up your development environment to run with Phidgets, we recommend you follow our guide on [[Phidget Programming Basics]]. The guide will showcase the fundamentals of programming with Phidgets, with examples in Python.


==Quick Downloads==
== Setup Guide ==


{{QuickDownloads|Python|
<div class="phd-deck-sequence">
{{APIQuickDownloads|http://www.phidgets.com/documentation/PythonDoc.zip}}|
{{PT3_PYTHON_CHOOSE}}{{PT3_PYTHON_WIN_PYCHARM}}{{PT3_PYTHON_WIN_PYCHARM_1}}{{PT3_PYTHON_WIN_PYCHARM_2}}{{PT3_PYTHON_WIN_PYCHARM_3}}{{PT3_PYTHON_WIN_CMD}}{{PT3_PYTHON_MAC_TRM}}{{PT3_PYTHON_LNX_TRM}}{{PT3_PYTHON_SBC_TRM}}{{PT3_PYTHON_WIN_LIC}}{{PT3_PYTHON_WIN_VS}}{{PT3_PYTHON_WIN_VS_1}}{{PT3_PYTHON_WIN_VS_2}}{{PT3_PYTHON_WIN_IDLE}}
{{ExampleQuickDownloads|http://www.phidgets.com/downloads/examples/Python.zip|}}|
{{ExtraLibraryQuickDownloads|http://www.phidgets.com/downloads/libraries/PhidgetsPython.zip|Python|}}
{{WindowsQuickDownloads}}
{{MacQuickDownloads}}
{{LinuxQuickDownloads}}
}}
==Getting started with Python==
 
If you are new to writing code for Phidgets, we recommend starting by running, then modifying existing examples. This will allow you to:
{{ExampleCodeReasons}}
 
Instructions are divided up by operating system. Choose:
*[[#Windows(2000/XP/Vista/7)|Windows 2000 / XP / Vista / 7]]
*[[#OS X |OS X]]
*[[#Linux | Linux]] (including PhidgetSBC)
 
==Windows (2000/XP/Vista/7)==
 
===Description of Library===
Python programs on Windows depend on the following. The installers in the [[#Libraries and Drivers | Quick Downloads]] section put only the {{Code|phidget21.dll}} into your system. You will need to manually put the Phidget Python Module into 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}}.
* <b>{{Code|Phidget Python Module}}</b> is the Phidget library for Python.
* <b>{{Code|setup.py}}</b> is used to install the Phidget module into the standard location for third party Python modules. On typical Python environments, this setup will install the Phidget Python module in the {{Code|site-packages}} directory.
 
If you do not want to use our installer, you can download the [http://www.phidgets.com/downloads/libraries/Phidget21-windevel.zip {{Code|phidget21.dll}}] and refer to our [[OS - Windows|Windows page]] for manual installation instructions.
 
The first thing you will have to do is to [[#Installing the Phidget Python Module |install the {{Code|Phidget Python Module}}]].
Afterwards, Running the examples and writing your own code can be fairly compiler-specific, so we include instructions for each environment below.
 
===Installing the Phidget Python Module===
 
Please start by downloading [http://www.phidgets.com/downloads/libraries/PhidgetsPython.zip Phidget Python Module]. After extracting the file, open up a command line terminal, traverse to the directory containing {{Code|setup.py}} and enter the following to install the Phidget Python module into the Python environment.
 
<div class="source">
<syntaxhighlight lang=bash>
python setup.py install
</syntaxhighlight>
</div>
 
===Command Line===
 
====Use Our Examples====
Please ensure that the Phidget Python Module is [[#Installing the Phidget Python Module | installed]] onto your system.
 
Next, download the [http://www.phidgets.com/downloads/examples/Python.zip examples] and unpack them into a folder.  While these examples were written in Python 3.0, they are also compatible with Python 2.5 (with a [[#All Operating Systems: The examples produces an error while running in a Python 2.5 environment. | minor modification]]). It is probably best to start with the HelloWorld program, which will work with any Phidget.  There is also an example file for your specific Phidget device.  {{FindYourDevice}}
 
Now, open up a command line prompt and navigate to the directory of the example folder.
 
Next, enter the following to run the example:
 
<div class="source">
<syntaxhighlight lang=bash>
python example.py
</syntaxhighlight>
</div>
 
Once you have the Python 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 environment to properly link the Phidgets Python libraries. Please see the [[#Use Our Examples| Use Our Examples ]] section for instructions.
 
Then, in your code, you will need to reference to the Phidget Python library.
 
<div class="source">
<syntaxhighlight lang=python>
from Phidgets.PhidgetException import *
from Phidgets.Events.Events import *
</syntaxhighlight>
</div>
 
Then, you will also have to add a reference to your particular Phidget.  For example, you would include the following line for a PhidgetInterfaceKit:
<div class="source">
<syntaxhighlight lang=python>
from Phidgets.Devices.InterfaceKit import *
</syntaxhighlight>
</div>
 
Please see the [http://www.phidgets.com/downloads/examples/Python.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.
 
===IDLE===
 
====Use Our Examples====
 
Please ensure that the Phidget Python Module is [[#Installing the Phidget Python Module | installed]] onto your system.
 
Next, download the [http://www.phidgets.com/downloads/examples/Python.zip examples] and unpack them into a folder.  While these examples were written in Python 3.0, they are also compatible with Python 2.5 (with a [[#All Operating Systems: The examples produces an error while running in a Python 2.5 environment. | minor modification]]). It is probably best to start with the HelloWorld program, which will work with any Phidget.  There is also an example file for your specific Phidget device.  {{FindYourDevice}} Now, open the example in the IDLE editor.
 
The only thing left to do is to run the examples! Click on Run &rarr; Run Module.
 
[[File:Python IDLE Run.PNG|link=|alt=Run?]]
 
Once you have the Python 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 environment to properly link the Phidget Python library. Please see the [[#Use Our Examples 2| Use Our Examples ]] section for instructions.
 
Then, in your code, you will need to reference to the Phidget Python library.
 
<div class="source">
<syntaxhighlight lang=python>
from Phidgets.PhidgetException import *
from Phidgets.Events.Events import *
</syntaxhighlight>
</div>
 
Then, you will also have to add a reference to your particular Phidget.  For example, you would include the following line for a PhidgetInterfaceKit:
<div class="source">
<syntaxhighlight lang=python>
from Phidgets.Devices.InterfaceKit import *
</syntaxhighlight>
</div>
 
Please see the [http://www.phidgets.com/downloads/examples/Python.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.
 
===Eclipse with PyDev===
 
====Use Our Examples====
 
1. Please ensure that the Phidget Python Module is [[#Installing the Phidget Python Module | installed]] onto your system.
 
2. Next, download the [http://www.phidgets.com/downloads/examples/Python.zip examples] and unpack them into a folder.  While these examples were written in Python 3.0, they are also compatible with Python 2.5 (with a [[#All Operating Systems: The examples produces an error while running in a Python 2.5 environment. | minor modification]]). It is probably best to start with the HelloWorld program, which will work with any Phidget.  There is also an example file for your specific Phidget device.  {{FindYourDevice}} You will need this example source code to be imported into your project later on.
 
3. Next, a new project will need to be created. Generate a new PyDev project with a descriptive name such as PhidgetTest.
 
[[File:Python PyDev New Project.PNG|link=|alt=New Project]]
 
4. To import the example program into your project, right click the Project and select {{Code|Import}}.
 
[[File:Python PyDev Import File 1.PNG|link=|alt=Import File]]
 
5. On the next screen, select {{Code|File System}} and proceed to the next screen.
 
[[File:Python PyDev Import File 2.PNG|link=|alt=Import File]]
 
6. Browse to the directory where you extracted the examples into, and select the example you wish to open.
 
[[File:Python PyDev Import File 3.PNG|link=|alt=Import File]]
 
7. The only thing left to do is to run the examples! Click on Run &rarr; Run.
 
[[File:Python PyDev Run.PNG|link=|alt=Run?]]
 
Once you have the Python 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 environment to properly link the Phidget Python library. Please see the [[#Use Our Examples 3 | Use Our Examples ]] section for instructions.
 
Then, in your code, you will need to include a reference to the Phidget Python library.
 
<div class="source">
<syntaxhighlight lang=python>
from Phidgets.PhidgetException import *
from Phidgets.Events.Events import *
</syntaxhighlight>
</div>
 
You will also have to add a reference to your particular Phidget.  For example, you would include the following line for a PhidgetInterfaceKit:
<div class="source">
<syntaxhighlight lang=python>
from Phidgets.Devices.InterfaceKit import *
</syntaxhighlight>
</div>
 
Please see the [http://www.phidgets.com/downloads/examples/Python.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.
 
==OS X==
 
The first step in using Python on Mac is to install the Phidget libraries.  Compile and install them as explained on the [[OS - OS X]] page, which also describes the different Phidget files, their installed locations, and their roles....
 
The next step is to install the Phidget Python module.  Download it here:
* [http://www.phidgets.com/downloads/libraries/PhidgetsPython.zip Phidget Python Module]
 
Then, unpack the module and enter the root of the newly unzipped directory.  There will be a script in the base directory called {{Code|setup.py}}.  This is used the same way as most other distributed Python modules - from a command line type:
 
<div class="source">
<syntaxhighlight lang=bash>
python setup.py install
</syntaxhighlight>
</div>
 
This will build the module and install the built python module files into your {{Code|site-packages}} directory.
 
===Use Our Examples===
 
First, download the examples:
*[http://www.phidgets.com/downloads/examples/Python.zip Phidget Python Examples]
 
Unpack them, and enter the root directory.  You will find examples specific to each Phidget device, as well as a {{Code|HelloWorld.py}} example.  The {{Code|HelloWorld.py}} code is probably the easiest example to run as it will work with any Phidget device.  Or you can use the example specific to your Phidget.  {{FindYourDevice}}
 
The Phidget examples were written in Python 3.0 and this tutorial assumes its use. However, they should still be compatible with Python 2.6. To run the examples using Python 2.5, you will need to modify the example code in the exception handling to read “except RuntimeError, e:”, instead of “except RuntimeError as e:”.
 
If needed, make those changes to the {{Code|HelloWorld.py}} example or the one for your Phidget. 
 
<div class="source">
<syntaxhighlight lang=bash>
python HelloWorld.py
</syntaxhighlight>
</div>
 
===Write Your Own Code===
 
When writing your code from scratch, you start it as you would any Python code, such as within a text editor like Emacs, Vi, Gedit, or Kate.  In your '''{{Code|.py}}''' source code file, you must include a reference to the Phidget module:
 
<div class="source">
<syntaxhighlight lang=python>
from Phidgets.PhidgetException import *
from Phidgets.Events.Events import *
</syntaxhighlight>
</div>
 
In addition, you should include the module functions for your specific device.  In the case of the Interface Kit, this would be:
 
<div class="source">
<syntaxhighlight lang=python>
from Phidgets.Devices.InterfaceKit import *
</syntaxhighlight>
</div>
 
For other devices, it would be the software object you found when running the examples above.  Then, you would run your Python code the same way as the examples.
 
To learn how to write your own code for your Phidget, and to learn more about our API, we have a [[#Follow the Examples|teaching]] section to help you follow the provided Python examples and which has resources such as the API reference.
 
==Linux==
 
Python has excellent support on Linux. 
 
The first step in using Python on Linux is to install the Phidget libraries.  These are the core Phidget libraries, written in C, which when compiled become part of the programming libraries available to your system.  Download, compile, and install from the links and instructions on the main [[OS - Linux | Linux page]].  That Linux page also describes the different Phidget files, their installed locations, and their roles.
 
The next step is to install the Phidget Python module.  Download it here:
* [http://www.phidgets.com/downloads/libraries/PhidgetsPython.zip Phidget Python Module]
 
Then, unpack the module and enter the root of the newly unzipped directory.  There will be a script in the base directory called {{Code|setup.py}}.  This is used the same way as most other distributed Python modules - from a command line type:
 
<div class="source">
<syntaxhighlight lang=bash>
python setup.py install
</syntaxhighlight>
</div>
 
This will build the module and install the built python module files into your {{Code|site-packages}} directory.
 
===Use Our Examples===
 
First, download the examples:
*[http://www.phidgets.com/downloads/examples/Python.zip Phidget Python Examples]
 
Unpack them, and enter the root directory.  You will find examples specific to each Phidget device, as well as a {{Code|HelloWorld.py}} example.  The {{Code|HelloWorld.py}} code is probably the easiest example to run as it will work with any Phidget device.  Or you can use the example specific to your Phidget.  {{FindYourDevice}}
 
The Phidget examples were written in Python 3.0 and this tutorial assumes its use. However, they should still be compatible with Python 2.6. To run the examples using Python 2.5, you will need to modify the example code in the exception handling to read “except RuntimeError, e:”, instead of “except RuntimeError as e:”.
 
If needed, make those changes to the {{Code|HelloWorld.py}} example or the one for your Phidget. 
 
Then, if you have not set up [[OS_-_Linux#Setting_udev_Rules|your udev rules for USB access]], you will need to run the Python example as '''root''':
 
<div class="source">
<syntaxhighlight lang=bash>
sudo python HelloWorld.py
</syntaxhighlight>
</div>
 
===Write Your Own Code===
 
When writing your code from scratch, you start it as you would any Python code on Linux, such as within a text editor like Emacs, Vi, Gedit, or Kate.  In your '''{{Code|.py}}''' source code file, you must include a reference to the Phidget module:
 
<div class="source">
<syntaxhighlight lang=python>
from Phidgets.PhidgetException import *
from Phidgets.Events.Events import *
</syntaxhighlight>
</div>
</div>


In addition, you should include the module functions for your specific device.  In the case of the Interface Kit, this would be:
<div class="source">
<syntaxhighlight lang=python>
from Phidgets.Devices.InterfaceKit import *
</syntaxhighlight>
</div>
For other devices, it would be the software object you found when running the examples above.  Then, you would run your Python code the same way as the examples.
To learn how to write your own code for your Phidget, and to learn more about our API, we have a [[#Follow the Examples|teaching]] section to help you follow the provided Python examples and which has resources such as the API reference.
==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.
Your main reference for writing Python code will be our Python API information, with syntax for all of our functions:
{{UsingAPhidgetInCodeGeneral|both of which are available in Python|[http://www.phidgets.com/documentation/PythonDoc.zip Python API]}}
===Example Flow===
{{ExamplePseudocode|In Python, you can name these '''event''' functions whatever you like.  You will then pass their function names 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 Python is specific to the Phidget.  For a Phidget Spatial, for example, this would involve creating a {{Code|Spatial}} object.  The examples show how to do this and other API functions.<br><br>
The object provides device specific methods and properties which are available from the API for your specific Phidget.|
[http://www.phidgets.com/documentation/PythonDoc.zip Python API]}}
===Code Snippets===
Specific calls in Python will differ in syntax from those on the [[General Phidget Programming]] page, but the concepts stay the same. 


It may help to have the [[General Phidget Programming]] page and this section open at the same time, because they parallel each other and you can refer to the Python syntax.  However, many additional concepts are covered on the General Phidget Programming page on a high level, such as using multiple Phidgets, handling errors, and different styles of programming.
== Quick Downloads ==


For example, if we were using a [[Product - 1018 - PhidgetInterfaceKit 8/8/8 | Phidget Interface Kit]] as our device, the general calls would look like this:
If you already know what you're doing and just need the files, you can find them all below.


====Step One: Initialize and Open====
=== Python Module ===
* [https://cdn.phidgets.com/downloads/phidget22/libraries/any/Phidget22Python.zip Phidget Python module]


<div class="source">
=== Documentation ===
<syntaxhighlight lang=python>
# Create
try:
  device = InterfaceKit()
except RuntimeError as e:
  print("Runtime Error: %s" % e.message)


# Open
*{{Phidget22API}}  (select Python from the drop-down menu)
try:
  device.openPhidget()
except PhidgetException as e:
  print (“Phidget Exception %i: %s” % (e.code, e.detail))
  exit(1)
</syntaxhighlight>
</div>


The variable {{Code|device}} is now a handle for the Phidget.  This example is ''specific to the Interface Kit'' because the call InterfaceKit() is used.  For another device, use the correspondingly named call in the Python API.
=== Example Code ===


The handle '''device''' is then used for all the Python function calls using the Phidget for its device-specific functions - in this case, Interface Kit specific functions.  Every type of Phidget also inherits functionality from the Phidget base class.
*{{SampleCode|Python|Python Examples}}


Note that open() opens the software object, but not hardware.  So, it is not a guarantee you can use the Phidget immediately.  The different types of open can be used with parameters to try and get the first device it can find, open based on its serial number, or even open across the network. The API manual lists all of the available modes that open provides.
===Libraries===
 
{{AllQuickDownloads}}
Also note that you can catch exceptions thrown by the Phidget library as we did above when using the openPhidget() call.  In other words, this should probably be present around most of your Phidget calls, especially when you are learning how to use the Phidget and debugging your code:
 
<div class="source">
<syntaxhighlight lang=python>
try:
  # Your code goes here
except PhidgetException as e:
  print (“Phidget Exception %i: %s” % (e.code, e.detail))
  exit(1)
</syntaxhighlight>
</div>
 
====Step Two: Wait for Attachment (plugging in) of the Phidget====
 
To use the Phidget, it must be plugged in (attached).  We can handle this simply by calling waitForAttachment. This function works for any Phidget. WaitForAttachment will block indefinitely until a connection is made to the Phidget, or an optional timeout is exceeded:
 
<div class="source">
<syntaxhighlight lang=python>
device.waitForAttach(10000)
print ("%d attached!" % (device.getSerialNum()))
</syntaxhighlight>
</div>
 
Sometimes, it makes more sense to handle the attachment via an event.  This would be in instances where the Phidget is being plugged and unplugged, and you want to handle these incidents.  Or, when you want to use event-driven programming because you have a GUI-driven program.  In these cases, an event-driven code snippet to handle the attachment might look something like this:
 
<div class="source">
<syntaxhighlight lang=python>
def AttachHandler(event):
    attachedDevice = event.device
    serialNumber = attachedDevice.getSerialNum()
    deviceName = attachedDevice.getDeviceName()
    print("Hello to Device " + str(deviceName) + ", Serial Number: " + str(serialNumber))
 
# Insert code for -creating- device here....
 
try:
    device.setOnAttachHandler(AttachHandler)
except PhidgetException as e:
    # Insert code for handling any exceptions
    # A common exception will occur if you do not create the device properly above
 
# Insert code for -opening- device here....
</syntaxhighlight>
</div>
 
====Step Three: 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.
 
For our [[Product - 1018 - PhidgetInterfaceKit 8/8/8 | Phidget Interface Kit]], the polling method of getting the current sensor state and setting an output state looks something like this:
 
<div class="source">
<syntaxhighlight lang=python>
 
# Get a data point from Analog Port 0
device.getSensorValue(0)
 
# Set digital output port 0 to be on
device.setOutputState(0, 1)
 
</syntaxhighlight>
</div>
 
To catch data changes via events, you would use something like this:
 
<div class="source">
<syntaxhighlight lang=python>
 
def sensorChanged(e):
  print (“Sensor %i: %i” % (e.index, e.value))
  return 0
 
# Insert code to create an Interface Kit called 'device'
 
# Hook our function above into the device object
device.setOnSensorChangeHandler(sensorChanged)
 
# Insert code to open 'device'
 
</syntaxhighlight>
</div>
 
====Step Four: Close and Delete====
 
At the end of your program, don’t forget to call closePhidget() to free any locks on the Phidget that the openPhidget() call put in place!
 
<div class="source">
<syntaxhighlight lang=python>
 
device.closePhidget()
 
</syntaxhighlight>
</div>
 
{{MoreHowTos}}
 
The ''complete'' set of functions you have available for all Phidgets can be found in the [http://www.phidgets.com/documentation/PythonDoc.zip Python API]. You can also find more description on any device-specific function in the Device API page for your specific Phidget, which can be found on its product page on our [http://www.phidgets.com main website].
 
 
==Common Problems and Solutions/Workarounds==
 
==={{ProblemSolution|OS X|My application hangs when using multiple devices in a single Python application.}}===
 
A call to {{Code|open}} may hang indefinitely if multiple devices are being programmed in a single Python application. To circumvent this, allow the application to delay a short period between {{Code|open}} calls. For most environments, a 1.25 millisecond delay is enough. For example:
<div class="source">
<syntaxhighlight lang=python>
import time
...
interface_kit.openPhidget(94695)
time.sleep(0.00125)
rfid.openPhidget(33502)
</syntaxhighlight>
</div>
 
 
==={{ProblemSolution|All Operating Systems|The examples produce an error while running in a Python 2.5 environment.}}===
 
Running the examples produces an error similar to the following:
<div class="source">
<syntaxhighlight lang=python>
InterfaceKit-simple.py:33: Warning: 'as' will become a reserved keyword in Python 2.6
  File "InterfaceKit-simple.py", line 33
    except RuntimeError as e:
SyntaxError: invalid syntax
</syntaxhighlight>
</div>
 
To run the example code in Python 2.5, all the lines containing:
<div class="source">
<syntaxhighlight lang=python>
except RuntimeError as e:
</syntaxhighlight>
</div>
will need to be replaced with:
<div class="source">
<syntaxhighlight lang=python>
except Runtime, e:
</syntaxhighlight>
</div>

Latest revision as of 22:06, 17 October 2023


We provide support for Python in all major operating systems. We also provide instructions on how to get your project started in a number of common development environments. Select your operating system and preferred development environment below, and follow the instructions to get your project running with Phidgets.

If you do not know which development environment you want to use, or your development environment of choice is not listed, we recommend starting with command line or terminal as the simplest path to getting your code running.

Once you have set up your development environment to run with Phidgets, we recommend you follow our guide on Phidget Programming Basics. The guide will showcase the fundamentals of programming with Phidgets, with examples in Python.

Setup Guide

Python - Select Development Environment

Select your Development Environment:

Windows

MacOS

Linux

PhidgetSBC

Language - Python

Windows with Pycharm

Welcome to using Phidgets with Python! By using Python, you will have access to the complete Phidget22 API, including events.

PyCharm is an integrated development environment for Python by JetBrains.

Requirements

First, make sure you have the following installed:

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

● Python (2.7 and 3.6+ are both compatible with Phidgets)

Installing the Phidget Python Module

Select your preferred installation method below:

PIP Install

PIP Global Install

Manual Install

The recommended way to install the Phidget22 Python module is using the PIP package manager.

«
»

Language - Python

Installing the Phidget Python Module

You can install the Phidget22 libraries for your current PyCharm project with PIP by opening File > Settings

Installing the Phidget Python Module

Next, navigate to Project > Project Interpreter and click on the + symbol located on the right:

Installing the Phidget Python Module

Type Phidget22 into the search bar, select the package named Phidget22 and click Install Package:

Finding Code Samples

To find the code sample to use for your Phidget, navigate to the Code Samples page and select your device from the drop-down menu.

Once you select your device, the code sample generator will give you a working code sample, and a selection of options to customize it to your needs.

Using the Code Samples

Click the Download Example button to download the sample code:

Using the Code Samples

Add the example you just downloaded by dragging it into the project:

Using the Code Samples

Finally, run the project:

The project is now running with Phidgets!

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.

«
»

Language - Python

Installing the Phidget Python Module

Python versions 2.7.9+ and 3.4+ include PIP by default. To install the Phidget22 Python module with PIP, simply open the Command Prompt (press the Windows key and search for cmd), and enter the command:

python -m pip install Phidget22

To install the Phidget22 libraries to a specific Python version, you can use the Python Windows Launcher from the Command Prompt as follows (replace -X.X with your Python version, e.g. -2.7 or -3.6):

py -X.X -m pip install Phidget22

Installing the Phidget Python Module

To use the global Phidget22 library in your PyCharm project, select Inherit global site-packages when creating a new project.

Finding Code Samples

To find the code sample to use for your Phidget, navigate to the Code Samples page and select your device from the drop-down menu.

Once you select your device, the code sample generator will give you a working code sample, and a selection of options to customize it to your needs.

Using the Code Samples

Click the Download Example button to download the sample code:

Using the Code Samples

Add the example you just downloaded by dragging it into the project:

Using the Code Samples

Finally, run the project:

The project is now running with Phidgets!

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.

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Language - Python

Installing the Phidget Python Module

To install the Phidget22 Python module without PIP, you need to download it here:

● Phidget22 Python Module

Unpack the Phidget22 Python module and open the Command Prompt (press the Windows key and search for cmd). Find the folder where you downloaded the Python module and enter this command:

python setup.py install

This will build the module and install the Python module files into your site-packages directory.

Finding Code Samples

To find the code sample to use for your Phidget, navigate to the Code Samples page and select your device from the drop-down menu.

Once you select your device, the code sample generator will give you a working code sample, and a selection of options to customize it to your needs.

Using the Code Samples

Click the Download Example button to download the sample code:

Using the Code Samples

Add the example you just downloaded by dragging it into the project:

Using the Code Samples

Finally, run the project:

The project is now running with Phidgets!

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.

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»

Language - Python

Windows with Command Line

Welcome to using Phidgets with Python! By using Python, you will have access to the complete Phidget22 API, including events.

The command line is the default environment to make Python programs in Windows, since it's available immediately after installing Python.

Requirements

First, make sure you have the following installed:

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

● Python (2.7 and 3.6+ are both compatible with Phidgets)

Installing the Phidget Python Module

Python versions 2.7.9+ and 3.4+ include PIP by default. To install the Phidget22 Python module with PIP, simply open the Command Prompt (press the Windows key and search for cmd), and enter the command:

python -m pip install Phidget22

To install the Phidget22 libraries to a specific Python version, you can use the Python Windows Launcher from the Command Prompt as follows (replace -X.X with your Python version, e.g. -2.7 or -3.6):

py -X.X -m pip install Phidget22

If you don't use PIP, follow the manual installation instructions on the next slide.

Installing the Phidget Python Module

To install the Phidget22 Python module without PIP, you need to download it here:

● Phidget22 Python Module

Unpack the Phidget22 Python module and open the Command Prompt (press the Windows key and search for cmd). Find the folder where you downloaded the Python module and enter this command:

python setup.py install

This will build the module and install the Python module files into your site-packages directory.

Finding Code Samples

To find the code sample to use for your Phidget, navigate to the Code Samples page and select your device from the drop-down menu.

Once you select your device, the code sample generator will give you a working code sample, and a selection of options to customize it to your needs.

Using the Code Samples

Click the Download Example button to download the sample code:

Using the Code Samples

To run the example, open the command prompt at the location of the example and enter the following command:

python example.py

The script is now running with Phidgets!

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.

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»

Language - Python

MacOS with Terminal

Welcome to using Phidgets with Python! By using Python, you will have access to the complete Phidget22 API, including events.

The terminal is the default environment to make Python programs in macOS, since it's available immediately after installing Python.

Requirements

First, make sure you have the following installed:

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

● Python (2.7 and 3.6+ are both compatible with Phidgets)

Installing the Phidget Python Module

Python versions 2.7.9+ and 3.4+ include PIP by default. To install the Phidget22 Python module with PIP, simply open the Terminal and enter the command:

python pip install Phidget22

If you don't use PIP, follow the manual installation instructions on the next slide.

Installing the Phidget Python Module

To install the Phidget22 Python module without PIP, you need to download it here:

● Phidget22 Python Module

After unpacking the Phidget Python module, open the terminal (Applications -> Utilities -> Terminal). Locate the folder containing the Python module and enter the following command:

python setup.py install

This will build the module and install the Python module files into your site-packages directory.

Finding Code Samples

To find the code sample to use for your Phidget, navigate to the Code Samples page and select your device from the drop-down menu.

Once you select your device, the code sample generator will give you a working code sample, and a selection of options to customize it to your needs.

Using the Code Samples

Click the Download Example button to download a Java file with the sample code:

Using the Code Samples

To run the example, open the command prompt at the location of the example and enter the following command:

python example.py

Success! Your program is now running with Phidgets!

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.

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»

Language - Python

Linux with Terminal

Welcome to using Phidgets with Python! By using Python, you will have access to the complete Phidget22 API, including events.

The terminal is the default environment to make Python programs in Linux, since it's available immediately after installing Python.

Requirements

First, make sure you have the following installed:

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

● Python (2.7 and 3.6+ are both compatible with Phidgets)

Installing the Phidget Python Module

Python versions 2.7.9+ and 3.4+ include PIP by default. To install the Phidget22 Python module with PIP, simply open the Terminal and enter the command:

Python 2.x :

pip install Phidget22

Python 3.x :

pip3 install Phidget22

If you don't use PIP, follow the manual installation instructions on the next slide.

Installing the Phidget Python Module

To install the Phidget22 Python module without PIP, you need to download it here:

● Phidget22 Python Module

After unpacking the Phidget Python module, open the terminal at folder location and enter the following command:

python setup.py install

This will build the module and install the Python module files into your site-packages directory.

Finding Code Samples

To find the code sample to use for your Phidget, navigate to the Code Samples page and select your device from the drop-down menu.

Once you select your device, the code sample generator will give you a working code sample, and a selection of options to customize it to your needs.

Using the Code Samples

Click the Download Example button to download a Java file with the sample code:

Using the Code Samples

To run the example, open the command prompt at the location of the example and enter the following command:

Python 2.x :

python Python_Example.py

Python 3.x :

python3 Python_Example.py

Success! Your program is now running with Phidgets!

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.

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»

Language - Python

PhidgetSBC with Python

Welcome to using Phidgets with Python! By using Python, you will have access to the complete Phidget22 API, including events.

Requirements

If you haven't already, check out the user guide in order to set up the following:

● Networking

● Administrator password


This guide will cover development using an external machine. For development using the SBC itself, go back and select Terminal - Linux as your environment.

Introduction

To begin, this video will help you get started:

Developing With An External Computer

There are two main ways in which you can access your SBC from an external computer:

● SBC Web Interface

● Secure Shell (SSH)


Since the SBC User Guide covers the web interface in detail, this guide will cover SSH.

SSH

If you are unfamiliar with SSH, it is a simple yet powerful tool that allows you to log into a remote machine in order to execute commands. You can also transfer files using the associated SCP tool.

In order to use SSH, you need the following:

● The SBC's IP address (e.g. 192.168.3.195) or the link local address (e.g. phidgetsbc.local)

● The administrator password

● SSH enabled on the SBC

SSH

You can enable SSH on the SBC Web Interface as shown below:

SSH on Windows

To use SSH on Windows, we recommend PuTTY. Use the images below as a guide for configuring PuTTY (use the IP address or the link local address interchangeably):

SSH on Windows

After clicking open, simply login as root and provide the administrator password:

To transfer files between your SBC and Windows machine, we recommend either of these programs:

● WinSCP

● PuTTY PSCP

You will follow a similar process to access the SBC as described for SSH.

SSH on Linux and macOS

SSH is available on Linux and macOS by default. To run SSH, open the terminal and type:

ssh root@phidgetsbc.local

Or, something like this (you will need to know the IP address of your SBC):

ssh root@192.168.3.195

You will then be prompted for the password in order to gain access to the SBC:

SSH on Linux and macOS

To copy a file from the SBC to your development machine using SCP, open the terminal and type:

scp root@phidgetsbc.local:/path/to/source /path/to/destination

You can reverse this if you want to transfer a file from your development machine to your SBC:

scp /path/to/source root@phidgetsbc.local:/path/to/destination

Installing Packages For Development

Installing support for Python has three steps:

  1. Ensure Include full Debian Package Repository is checked on the SBC Web Interface (System->Packages)
  2. Install Python
  3. Install Phidget Python module

You will need to run commands on the SBC to install support for Python. You can either use SSH to issue the commands, or you can connect directly to the SBC via a monitor and keyboard.

Installing Python

The base Python functionality can be downloaded and installed in one step:

apt-get install python

Installing the Phidgets Module

Next, you need to install the Phidget Python module. You have three options:

Using PIP

The recommended way to install the Phidget22 Python module is using the PIP package manager.

Python versions 2.7.9+ and 3.4+ include PIP by default.

To install the Phidget22 Python module with PIP, simply run the command: 

python -m pip install Phidget22

Manual Install Using the Internet

First, install wget and unzip: 

apt-get install wget
apt-get install unzip

Next, copy the web link address for the Python Libraries and use it in the following command (right click to copy into a terminal): 

wget http://copied_link

The Phidget Python libraries should now be downloaded in the folder you ran the previous command in. The next step is to unzip the file: 

unzip filename

Finally, change directories to the unzipped folder: 

cd /path/to/unzipped/folder

and install the Phidget Python libraries: 

python setup.py install

Using a USB Key

Copy the Python Libraries onto a USB key. Unpack the zip file into a folder on the USB key. Insert the key into the SBC.

You will have to figure out where the USB key (and the Phidget Python library folder) is now located. Next, run the following commands (be sure to modify the usb directory number if necessary): 

cd /media/usb0/
python setup.py install

You're now ready to begin programming! Continue through this guide for code examples and directions on where to go next.

Finding Code Samples

To find the code sample to use for your Phidget, navigate to the Code Samples page and select your device from the drop-down menu.

Once you select your device, the code sample generator will give you a working code sample, and a selection of options to customize it to your needs.

Using the Code Samples

If it's unclear what any of the options do, click on the nearby '?' for more info.

Once you've made your selections, click the Download Example button under Downloads.

Setting up a New Project

When developing on an external computer, you will write, compile, and test your programs on that machine. When you are ready, you will then upload your programs to the SBC to compile and run them.

Setting up a New Project

Once your code is written, follow these steps to get your program running on the SBC:

1. Using the SBC Web Interface, create a new project:

Setting up a New Project

2. Transfer all the project files from the development machine to the SBC, either using the SBC Web Interface or a tool like WinSCP.

The project directory will be:

/usr/userapps/ProjectName

Setting up a New Project

3. Use SSH to access the SBC terminal and go to the project folder:

cd /usr/userapps/ProjectName

You can now run the program with the command:

python ExampleName.py

Success! The program is running on your SBC.

Running a Program Automatically

To run a Python script as a standalone application, you will need to add a line called a "shebang" to the top of the script, with the path to your Python executable. If you have followed the steps in this guide, the line will be:

#!/usr/bin/python

Click on the sections below for various automation options:

-----

Running a Program from the SBC Web Interface

To quickly test whether a program can be run automatically, you can try starting it from the SBC Web Interface.

1. To start the program, navigate to Projects->ProjectName->Startup Settings in the SBC Web Interface.

2. Select your program in the drop-down menu labeled Executable/Class Name.



3. Click the Start button on the SBC web interface.


4. You'll note that as it runs, there are two links below the Stop button which can be used to view the program output:

  • stdout: view the program output like you would in a terminal or command prompt
  • stderr: view the program error output
Run on Boot

Running on boot ensures that your program will never miss an event. As long as the SBC is running, your code will be running. This section assumes you have written and compiled your program on an external computer, and have uploaded it to the SBC Web Interface.


To have your program run on boot, navigate to Projects->ProjectName->Startup Settings in the SBC Web Interface. After selecting your project, copy the settings from the image below:



We will review some of the options that are shown in the image above:

  • Startup Order: lower numbers boot first. Booting later means more programs are available for use, booting earlier means other programs can use your program.
  • Run as a daemon: starts the program as a daemon. Unless you have explicitly written your program as a daemon, leave this checked, or else your SBC may hang on boot.
  • Executable/Class name: your main Java class or C file.
  • Arguments: any command line arguments the program needs.

After saving your changes, your program will run automatically whenever your SBC boots.

Run on a Schedule

Running your program on a schedule allows you to perform your task once a week, or once a minute without worrying about memory management issues or instability problems that may arise. It executes, and then gets cleaned up. To run your program on a schedule, we recommend using Cron. Cron can automatically schedule programs (known as jobs, or cron jobs). Cron simply reads a crontab file and runs whatever programs are listed, with whatever timing they are listed with. Cron runs continuously in the background, but the cron jobs only run as long as they naturally would, and then they exit.


Let's set up your first cron job. We will use nano to edit the crontab file, but feel free to use whatever editor you prefer.


First, set your editor to nano: 

export EDITOR=nano

Next, edit your crontab file: 

crontab -e

Finally, schedule your cron job: 

#cron job that will run at 5AM every week:
0 5 * * 1 /root/code/myprogram argument1


After entering your task, simply save and exit the file.

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.

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»

Language - Python

Windows with LiClipse

Welcome to using Phidgets with Python! By using Python, you will have access to the complete Phidget22 API, including events.

LiClipse is a closed-source development environment based on Eclipse, with support for Python.

Requirements

First, make sure you have the following installed:

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

● Python (2.7 and 3.6+ are both compatible with Phidgets)

Installing the Phidget Python Module

Python versions 2.7.9+ and 3.4+ include PIP by default. To install the Phidget22 Python module with PIP, simply open the Command Prompt (press the Windows key and search for cmd), and enter the command:

python -m pip install Phidget22

To install the Phidget22 libraries to a specific Python version, you can use the Python Windows Launcher from the Command Prompt as follows (replace -X.X with your Python version, e.g. -2.7 or -3.6):

py -X.X -m pip install Phidget22

If you don't use PIP, follow the manual installation instructions on the next slide.

Installing the Phidget Python Module

To install the Phidget22 Python module without PIP, you need to download it here:

● Phidget22 Python Module

Unpack the Phidget22 Python module and open the Command Prompt (press the Windows key and search for cmd). Find the folder where you downloaded the Python module and enter this command:

python setup.py install

This will build the module and install the Python module files into your site-packages directory.

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 Python library.

To start, create a new Python project:

Setting Up a New Project

Next, add a new file to the project:

Finding Code Samples

To find the code sample to use for your Phidget, navigate to the Code Samples page and select your device from the drop-down menu.

Once you select your device, the code sample generator will give you a working code sample, and a selection of options to customize it to your needs.

Using the Code Samples

If it's unclear what any of the options do, click on the nearby '?' for more info.

Once you've made your selections, click the copy button and paste the code into your new project.

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.

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Language - Python

Windows with Visual Studio

Welcome to using Phidgets with Python! By using Python, you will have access to the complete Phidget22 API, including events.

Visual Studio is an IDE provided by Microsoft that can be used to develop code in a wide variety of programming languages, including Python.

Requirements

First, make sure you have the following installed:

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

● Python (2.7 and 3.6+ are both compatible with Phidgets)

Installing the Phidget Python Module

Select your preferred installation method below:

PIP Install

Manual Install

The recommended way to install the Phidget22 Python module is using the PIP package manager.

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Language - Python

Installing the Phidget Python Module

You can install the Phidget22 libraries for your current Visual Studio project with PIP by opening View > Other Windows > Python Environments

Installing the Phidget Python Module

Next, select Packages (PyPI) from the drop-down menu:

Installing the Phidget Python Module

Type Phidget22 into the search bar, then click Install Phidget22:

Success! Your project now has access to Phidget22.

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 Python library.

To start, create a new Python project:

Setting Up a New Project

Then open the Python file that was generated with the project.

Finding Code Samples

To find the code sample to use for your Phidget, navigate to the Code Samples page and select your device from the drop-down menu.

Once you select your device, the code sample generator will give you a working code sample, and a selection of options to customize it to your needs.

Using the Code Samples

If it's unclear what any of the options do, click on the nearby '?' for more info.

Once you've made your selections, click the copy button and paste the code into your new project.

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.

«
»

Language - Python

Installing the Phidget Python Module

To install the Phidget22 Python module without PIP, you need to download it here:

● Phidget22 Python Module

Unpack the Phidget22 Python module and open the Command Prompt (press the Windows key and search for cmd). Find the folder where you downloaded the Python module and enter this command:

python setup.py install

This will build the module and install the Python module files into your site-packages directory.

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 Python library.

To start, create a new Python project:

Setting Up a New Project

Then open the Python file that was generated with the project.

Finding Code Samples

To find the code sample to use for your Phidget, navigate to the Code Samples page and select your device from the drop-down menu.

Once you select your device, the code sample generator will give you a working code sample, and a selection of options to customize it to your needs.

Using the Code Samples

If it's unclear what any of the options do, click on the nearby '?' for more info.

Once you've made your selections, click the copy button and paste the code into your new project.

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.

«
»

Language - Python

Windows with IDLE

Welcome to using Phidgets with Python! By using Python, you will have access to the complete Phidget22 API, including events.

IDLE is a cross-platform development environment for Python targeted at newcomers to the language.

WARNING: We do not recommend using Idle with Phidgets. It has known problems dealing with multiple threads, which is a required feature if your program uses events.

Requirements

First, make sure you have the following installed:

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

● Python (2.7 and 3.6+ are both compatible with Phidgets)

Installing the Phidget Python Module

Python versions 2.7.9+ and 3.4+ include PIP by default. To install the Phidget22 Python module with PIP, simply open the Command Prompt (press the Windows key and search for cmd), and enter the command:

python -m pip install Phidget22

To install the Phidget22 libraries to a specific Python version, you can use the Python Windows Launcher from the Command Prompt as follows (replace -X.X with your Python version, e.g. -2.7 or -3.6):

py -X.X -m pip install Phidget22

If you don't use PIP, follow the manual installation instructions on the next slide.

Installing the Phidget Python Module

To install the Phidget22 Python module without PIP, you need to download it here:

● Phidget22 Python Module

Unpack the Phidget22 Python module and open the Command Prompt (press the Windows key and search for cmd). Find the folder where you downloaded the Python module and enter this command:

python setup.py install

This will build the module and install the Python module files into your site-packages directory.

Finding Code Samples

To find the code sample to use for your Phidget, navigate to the Code Samples page and select your device from the drop-down menu.

Once you select your device, the code sample generator will give you a working code sample, and a selection of options to customize it to your needs.

Using the Code Samples

If it's unclear what any of the options do, click on the nearby '?' for more info.

Once you've made your selections, click the copy button.

Using the Code Samples

Paste the sample code into a new Python script file in IDLE:

Using the Code Samples

To run the example, simply click on Run and select Run Module:

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.

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»


Quick Downloads

If you already know what you're doing and just need the files, you can find them all below.

Python Module

Documentation

Example Code

Libraries

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