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<metadesc>Communicate over USB with sensors, controllers and relays with Phidgets! Program in Linux using a wide variety of programming languages.</metadesc>
[[Category:OS]]
[[Category:OS]]
__TOC__
==Quick Downloads==
Already know what you're doing? Here you go:
*[{{SERVER}}/downloads/phidget22/libraries/linux/libphidget22.tar.gz Phidget22 Library for Linux]
*[{{SERVER}}/downloads/phidget22/libraries/linux/libphidget22extra.tar.gz Phidget22Extra Library for Linux] (Required for Network Server)
*[{{SERVER}}/downloads/phidget22/servers/linux/phidget22networkserver.tar.gz Phidget Network Server for Linux]
*[{{SERVER}}/downloads/phidget22/tools/linux/phidget22admin.tar.gz PhidgetAdmin Tool for Linux]
*[[Software License]]


If you need older versions of the Linux libraries, [{{SERVER}}/downloads/phidget22/libraries/linux/libphidget22/ click here].
==Getting Started with Linux==
Welcome to using Phidgets with Linux!
 
===Install===
The first step to using Phidgets with Linux is installing the Phidget22 libraries.


==Getting Started with Linux==
We provide prebuilt packages for Debian, Ubuntu, and their derivatives.
Welcome to using Phidgets with Linux. If you haven't already, check out the [[:Category:UserGuide|user guide]] for your device. If you are ready to go, the first step in creating Linux applications with Phidgets is installing the Phidget libraries!


===Installing===
If you're running a supported distros, we recommend using the '''Package Install'''. For other systems, you can use the '''Source Install'''.  
If your Linux machine is running Debian, keep reading. For all other Linux distributions, jump ahead to [[#Generic Install | generic installs]].
====Debian Install====
To install the Phidget libraries on Debian, follow theses steps:


1. Enter the following command in the terminal:
<div class="bigTabs">
<syntaxhighlight lang=bash>
<tabber>
wget -qO- http://www.phidgets.com/gpgkey/pubring.gpg | apt-key add -
|-|Package Install=
</syntaxhighlight>
{{LinuxPackageInstall}}


2. If you are running jessie (Debian 8), enter the following command:
|-|Source Install=
====Source Install====
To install our libraries, first install libusb-1.0 development libraries. The exact command and package name will vary depending on distribution. For Debian based distributions, including Ubuntu and Mint, the command would be:
<syntaxhighlight lang=bash>
<syntaxhighlight lang=bash>
echo 'deb http://www.phidgets.com/debian jessie main' > /etc/apt/sources.list.d/phidgets.list
apt install libusb-1.0-0-dev
</syntaxhighlight>
</syntaxhighlight>
We also support squeeze (Debian 6), and wheezy (Debian 7). If you are running one of these older releases, simply replace ''jessie'' in the command above with your release.


3. Next, update your package lists:
<syntaxhighlight lang=bash>
apt-get update
</syntaxhighlight>


4. Finally, install the recommended packages by entering the command below:
Next, download and unpack the following files:
<syntaxhighlight lang=bash>
*[https://cdn.phidgets.com/downloads/phidget22/libraries/linux/libphidget22.tar.gz libphidget22] (Mandatory)
apt-get install libphidget22 libphidget22-dev phidget22networkserver libphidget22java phidget22admin
*[https://cdn.phidgets.com/downloads/phidget22/libraries/linux/libphidget22extra.tar.gz libphidget22extra] (Optional - needed by NetworkServer and Admin)
</syntaxhighlight>
*[https://cdn.phidgets.com/downloads/phidget22/libraries/linux/libphidget22java.tar.gz libphidget22java] (Optional - Java Libraries)
*[https://cdn.phidgets.com/downloads/phidget22/servers/linux/phidget22networkserver.tar.gz phidget22networkserver] (Optional - [[Phidget Network Server]])
*[https://cdn.phidgets.com/downloads/phidget22/tools/linux/phidget22admin.tar.gz phidget22admin] (Optional - Phidget Admin Tool)
Open the README file that is included at the top of each directory. This file will give you important information about how to properly install the files.




You have finished installing the Phidget libraries onto your Debian machine. Next, we will verify everything is working properly. Jump ahead to [[#Verify | verifying]].
Libraries are installed in /usr/local/lib by default. If you run into trouble finding the libraries during linking or at runtime, this probably means that /usr/local/lib is not on the library path for your distribution.


====Generic Install====
You can handle this in a number of ways:
To install the Phidget libraries, follow these steps:


1. Install libusb-1.0 development libraries by entering the command into the terminal:
Specify a different install folder during compile
<syntaxhighlight lang=bash>
<syntaxhighlight lang=bash>./configure --prefix=/usr && make && sudo make install</syntaxhighlight>
apt-get install libusb-1.0-0-dev
OR Add /usr/local/lib to the system-wide library path
</syntaxhighlight>
<syntaxhighlight lang=bash>echo /usr/local/lib >> /etc/ld.so.conf && sudo ldconfig</syntaxhighlight>
OR Add /usr/local/lib in your local shell every time
<syntaxhighlight lang=bash>export LD_LIBRARY_PATH=$LD_LIBRARY_PATH:/usr/local/lib</syntaxhighlight>


2. Download and unpack the following files:
The libraries are now installed on your machine. Next, you should set the UDev Rules.
*[{{SERVER}}/downloads/phidget22/libraries/linux/libphidget22.tar.gz libphidget22]
</tabber>
*[{{SERVER}}/downloads/phidget22/libraries/linux/libphidget22extra.tar.gz libphidget22extra]
</div>
*[{{SERVER}}/downloads/phidget22/libraries/linux/libphidget22java.tar.gz libphidget22java]
*[{{SERVER}}/downloads/phidget22/libraries/linux/phidget22networkserver.tar.gz phidget22networkserver]
*[{{SERVER}}/downloads/phidget22/libraries/linux/phidget22admin.tar.gz phidget22admin]


=== Setting UDev Rules ===
By default, Linux will not grant permission to regular users to access physical hardware as a security feature.  This means that in order to run Phidgets code from user space you must grant yourself root privileges via sudo.  For example:


3. Open the README file that is included at the top of each directory. This file will give you important information about how to properly install the files.
sudo ./HelloWorld


You can grant access manually or, more commonly, set up a rules file to do it automatically keying off of the vendor code for Phidget USB devices.  To do this, create a text file called "99-libphidget22.rules" with the following contents:
<syntaxhighlight lang=bash>
# All current and future Phidgets - Vendor = 0x06c2, Product = 0x0030 - 0x00af
SUBSYSTEMS=="usb", ACTION=="add", ATTRS{idVendor}=="06c2", ATTRS{idProduct}=="00[3-a][0-f]", MODE="666"
</syntaxhighlight>


You have finished installing the Phidget libraries onto your Linux machine. Next, we will verify everything is working properly.
Where mode 666 means every user has permission to read and write to the specified file/device.  You need to then move this file to "/etc/udev/rules.d".  Now you can run Phidget related code as a regular user without the OS denying permission.


===Verify===
===Verify===
The best way to verify that your libraries are installed and your Phidget is working is to compile and run the [{{SERVER}}downloads/phidget22/examples/c/Manager/Phidget22_HelloWorld_C_Ex.zip HelloWorld C example]. To compile and run the example, follow these steps:
The best way to verify that your libraries are working properly is to compile and run an example program.




1. Unpack the C examples and open a terminal window at this location
First, download and unpack this C example:
*[https://cdn.phidgets.com/downloads/phidget22/examples/c/Manager/Phidget22_HelloWorld_C_Ex.zip HelloWorld C example]


2. Compile the HelloWorld.c example:
'''Note:''' If using the Debian intallation methods, you will need to install the '''libphidget22-dev''' package to use the C libraries for Phidget22


Next, open the terminal at the example location. Compile the example by entering the following command:
<syntaxhighlight lang=bash>
<syntaxhighlight lang=bash>
  gcc HelloWorld.c -o HelloWorld -lphidget22
  gcc HelloWorld.c -o HelloWorld -lphidget22
</syntaxhighlight>
</syntaxhighlight>


3. Run the HelloWorld example:
 
Run the HelloWorld example:
<syntaxhighlight lang=bash>
<syntaxhighlight lang=bash>
./HelloWorld
./HelloWorld
</syntaxhighlight>
</syntaxhighlight>


Your terminal should look something like this:
Your terminal should look something like this:
[[File:linux_helloworld.PNG|link=|center]]
[[File:linux_helloworld.PNG|link=|center]]


Line 92: Line 92:
Your Phidget is now able to communicate with your development machine. The next step is selecting a programming language so you can start to write some code!
Your Phidget is now able to communicate with your development machine. The next step is selecting a programming language so you can start to write some code!


===Programming===
==Programming==
Ready to write some code? Select one of the programming languages below:
Ready to write some code? Select one of the programming languages below:


''Great choices for beginners:''
{{Programming_Languages_Table}}
*[[Language - C/C++|C/C++]]
*[[Language - Java | Java]]
*[[Language - Python | Python]]
''Also supported:''
*[[Language - C Sharp | C#]]
*[[Language - Visual Basic .NET | VB.Net]]
*[[Language - JavaScript | JavaScript]]
 
==Phidget Network Server==
The Phidget Network Server is an extremely useful feature of Phidgets that allows you to remotely control Phidgets over your network. If you haven't already, check out the [[Phidget Network Server]] page for a complete overview.
 
===Try it out!===
In order to try the Phidget Network Server out, you will need a host computer, and a client computer with the Phidget libraries installed:
*Host computer: the computer that is physically connected to the Phidgets via USB and is running the Phidget Network Server.
*Client computer: a computer running a Phidgets application that accesses Phidgets connected to the host computer.
If you only have one computer, don't worry, your machine can act as both a host and a client.
 
 
Next, follow these steps:
 
1. Open the terminal on the host computer and type in the following command:
<syntaxhighlight lang=bash>
phidget22networkserver
</syntaxhighlight>
 
[[File:Linux_networkserver.PNG|link=|center]]
 
 
The Network Server is now running on your machine with the default configuration. If you would like to change the Network Server configuration, you can do so by modifying the following file:
*/etc/phidgets/phidget22networkserver.pc
 
 
Now that you have the Network Server running on your host computer, the next step will be accessing the Phidgets connected to your host computer from your client computer. Follow the steps below:
 
 
1. Open the terminal on the client computer and type in the following command (if you are using a single machine, simply open a new terminal session and continue):
<syntaxhighlight lang=bash>
phidget22admin -s
</syntaxhighlight>
 
 
[[File:Linux_networkserver_phidgetadmin.PNG|link=|center]]
 
 
This will list all of the Phidget Servers on your network. You will see the Network Server running on the host computer (phidgetsdebian in this case).
 
 
2. Next, type in the following command:
<syntaxhighlight lang=bash>
phidget22admin -R -d
</syntaxhighlight>
 
 
[[File:Linux_networkserver_phidadminlist.PNG|link=|center]]
 
 
You will now see any Phidgets attached to your host computer in the list, as shown above. Any Phidget in the list can be accessed remotely from a Phidgets application. Every programming language we support comes with example code on how to remotely access a Phidget.
 
Now that you have seen the Network Server in action, you may be interested in having it run on boot. If so, keep reading. If you want to get started writing a Phidgets application that takes advantage of the Network Server, jump back to the [[#Programming|programming languages]] section.
 
 
===Starting Network Server on boot===
 
==Advanced Information==
 
===Setting udev Rules===
 
If you don't want to be using {{Code|sudo}} to run Phidget programs (including the Network Server) forever, you will want to create a {{Code|udev}} rule to allow yourself access to the Phidget when you are not root.
 
Udev has an easy way to set the owner and permissions of the USB interface of the Phidget - it finds all devices that match a given set of rules, and applies new traits to them.  But you need to give udev something to match in order to apply the new settings.  Here, we will tell udev to match the vendor code for Phidgets, Inc. 
 
We recommend that you use the rules file included in the library download you have already installed.  Check the README file included in that download for information on how exactly to install it, or continue reading here. 
 
The rules for udev are kept in files in {{Code|/etc/udev/rules.d/}} and are traditionally grouped into order of running (10 runs before 20, 30, etc) and device type (cd, network, etc).  There should be one or more files in there already. Simply find the file named {{Code|99-libphidget22.rules}} included with our library files, and move it into {{Code|/etc/udev/rules.d/}}.
 
Strictly speaking, the files run in lexical order (i.e. the order they're listed when you use {{Code|ls}}).  A device can match many rules, and all will apply (if possible).  If conflicting rules are found, the first rule found is followed.
 
===Starting the Network Server at Boot===
 
If you are tired of starting the network server on the command line all the time, you can have the network server start when your system starts, every time.
 
====User Space====
 
If you are running a standard Linux machine with an X-server (Unity, KDE) the easiest way to do this is to have the Phidget Network Server start when your x server starts.
 
In this case, the network server will be running in user space, so your [[#Setting udev Rules|udev rules need to be set up]] for the your user permissions to be able to access the USB ports using libusb.
 
Within the X-windowing system, there is usually some sort of {{Code|System &rarr; Settings/Preferences &rarr; Startup}} that you can choose to add programs that start when a user session starts.  On Ubuntu you can use Unity to find programs listing "startup" in their names to accomplish the same thing.  This will eventually lead you to a window like this one:
 
[[Image:linux_ws_boot.png|400px|link=]]
 
Simply add the {{Code|/usr/bin/phidget22networkserver}} program to the list.
 
====As A Service====
 
You would want to set the boot start of {{Code|phidgetnetworkserver21}} to be a service if you are running a server, or a headless machine.  It is handy any time you need the network server to be started as a booted, respawning service with a presence in different run levels and for all users.
 
A service is essentially a program that hangs out in the background, waiting to be used by some incoming task.  When the service is needed, the service forks a program to handle that need.  Most services that run on your Linux computer already have the ability to fork themselves. 
 
The network server, however, is just a binary on Linux - {{Code|phidgetnetworkserver21}} - and so we need a program that handles the forking for us.  For this, we use the {{Code|start-stop-daemon}} program to spawn a standalone process for us, or kill it, based on our service-like start, stop, and restart commands.
 
To do this, we need:
# A script that tells the boot process how to start and handle the networkserver (i.e. by using {{Code|start-stop-daemon}})
# A link from that script to the boot list
# An initialization file for the script
 
First, the script.  We will walk through Debian here, both because it is such a common distribution and because it is the distribution that our [{{SERVER}}/products.php?product_id=1073 Single Board Computer] runs.  But {{Code|init}} is surprisingly diverse on Linux, including everything from a different boot order, to different initialization programs and structure, and even different runlevels. 
 
On Debian (including Ubuntu), the initialization script covers:
* Runlevels that the service should be present on
* Dependencies of the service
* Name of the service and other informative data
* The location of the PIDFILE, which stores the process ID (pid) for later dealing with a spawned instance
* Any configuration file locations
* What to do when the service is given instructions to '''start''', '''stop''', or '''reload'''.
 
The Debian script we use to start the network server on the [{{SERVER}}/products.php?product_id=1073 Single Board Computer]:
 
<syntaxhighlight line start="1" lang=bash>
 
#!/bin/sh
 
### BEGIN INIT INFO
# Provides:          phidgetnetworkserver
# Required-Start:    $network $remote_fs
# Required-Stop:    $network $remote_fs
# Should-Start:      avahi
# Should-Stop:      avahi
# Default-Start:    2 3 4 5
# Default-Stop:      0 1 6
# Short-Description: Phidget Network Server
# Description:      Phidget Network Server for controlling Phidgets over the network.
### END INIT INFO
 
DESC="Phidget Network Server"
NAME=phidgetnetworkserver
BIN=phidgetnetworkserver21
DAEMON=/usr/bin/$BIN
PIDFILE=/var/run/$NAME.pid
CFG=/etc/default/$NAME
 
# Gracefully exit if the package has been removed.
test -x $DAEMON || exit 0
 
# load config
pws_port="5001"
pws_serverid=""
pws_password=""
[ -f $CFG ] && . $CFG
 
start() {
[ -z "$pws_port" ] || OPTIONS="-p $pws_port "
[ -z "$pws_password" ] || OPTIONS="$OPTIONS-P $pws_password "
 
if [ -z "$pws_serverid" ]; then
OPTIONS="$OPTIONS -n $( hostname )"
else
OPTIONS="$OPTIONS -n $pws_serverid"
fi
echo -n "Starting $DESC: "
start-stop-daemon -S -b -q -p $PIDFILE -m -x $DAEMON -- $OPTIONS && echo "OK" || echo "ALREADY RUNNING"
}
 
stop() {
echo -n "Stopping $DESC: "
start-stop-daemon -K -q -p $PIDFILE -x $DAEMON && echo "OK" || echo "NOT RUNNING"
}
 
case "$1" in
  start)
start
;;
  stop)
stop
;;
  restart|force-reload)
stop
sleep 1
start
;;
  *)
echo "Usage: $0 {start|stop|restart}"
esac
 
exit 0
</syntaxhighlight>
 
 
Save the script into a file called {{Code|phidgetnetworkserver}}, and use {{Code|chmod 755}} to make it executable.
 
Also on Debian, startup service scripts should go in {{Code|/etc/init.d}}, and then put within the appropriate runlevel-numbered folder - by symbolic link.  There is a handy tool to do this for you, called {{Code|insserv}}:
 
<syntaxhighlight lang=bash>
sudo insserv -d phidgetnetworkserver
</syntaxhighlight>
 
 
The {{Code|insserv}} program is the program that makes use of the {{Code|### BEGIN INIT INFO...### END INIT INFO}} that appears at the top of the {{Code|phidgetnetworkserver}} script.  Use {{Code|man insserv}} for more information.  The {{Code|insserv}} tool handles the mess of finding the right runlevel folders (i.e. the {{Code|rc.d}} numbered folders) and making the appropriate links. You can see what links would be updated by running {{Code|insserv}} with the {{Code|-n}} option, for a dry run.
 
'''Note:''' When you run {{Code|insserv}}, all of the dependencies for the boot order are re-written.  This means that all of the initialization scripts in {{Code|/etc/init.d}} are re-examined.  So, you'll probably get a lot of output when you run the command.
 
Then, you can check that {{Code|phidgetnetworkserver}} is on the service list with:
 
<syntaxhighlight lang=bash>
service --status-all
</syntaxhighlight>
 
 
And you can start it right now without rebooting like this:
 
[[Image:linux_system_service_start.png|link=]]
 
The {{Code|service}} command has many options to start and stop services like the phidgetnetworkserver, try {{Code|man service}} for more information.
 
At this point, you can follow the client instructions on [[#Using the Network Server|using the network server]] to create a loopback test for the new network server that should now be running.
 
The final piece, for future configuration changes, is that the {{Code|/etc/init.d}} script looks for the file {{Code|/etc/default/phidgetnetwork server}} upon starting up.  The file is expected to contain the port, server ID, and password for the server side of the network server.  These are also set in the {{Code|phidgetnetworkserver}} script in {{Code|init.d}}, as you can see from reading the code above, but if you want to change them a lot, you can edit the configuration file rather than changing the {{Code|phidgetnetworkserver}} script and re-installing by {{Code|insserv}} every time.  The configuration file in {{Code|/etc/default/}} should contain the same syntax as that used in the script source above:
 
<syntaxhighlight lang=bash>
pws_port="5001"
pws_serverid=""
pws_password=""
</syntaxhighlight>
 
===Cross-Compiling with a Custom Toolchain===
 
This would allow you to have the Phidget libraries compiled to include in code for an embedded device.  When developing for an embedded device, you will often write code for it on your 'normal' computer, and then build the code to binary with a different target than the processor in your computer.  Many microcontrollers do not have the ability to run a full operating system, and hence cannot compile code natively. 
 
The collection of tools used to create binary code for a separate system is called a ''toolchain''.  Compiling the Phidget libraries specifically for an embedded system, and placing them into the path for writing code on top of the libraries is like adding another link in this chain.
 
You can use the typical {{Code|./configure}} setup for custom build targets:
 
<syntaxhighlight lang=bash>
./configure --prefix=toolchain_location --build=this_system --host=target_system
</syntaxhighlight>
 
For the Phidget libraries, the {{Code|./configure}} tool works this way as well. You'd use this in the [[#Installing|install the libraries section]] setup. For example, let's say you're building the libraries to develop code for the [{{SERVER}}/products.php?product_id=1073 Single Board Computer] as a target.  Your system is a standard Linux system (i686-pc-linux-gnu) and the target system for the SBC is {{Code|arm-linux-gnueabi}}.  For this target, you'll need the base of the GNU embedded Debian chain:
 
<syntaxhighlight lang=bash>
sudo apt-get install gcc-arm-linux-gnueabi
</syntaxhighlight>
 
 
Then, download the Phidget libraries [[#Quick Downloads|above]] and unpack them into a folder {{Code|phidget_libraries}}.  If {{Code|/usr/arm-linux-gnueabi}} is the location of your ARM toolchain (downloaded above in {{Code|gcc-arm-linux-gnueabi}}), type:
 
<syntaxhighlight lang=bash>
~/phidget_libraries $> ./configure --prefix=/usr/arm-linux-gnueabi --build=i686-pc-linux-gnu --host=arm-linux-gnueabi
</syntaxhighlight>
 
 
===Linux on Non-Standard Systems===
 
We occasionally get requests to use Phidgets on Linux systems other than a standard laptop or desktop.  One example is the Raspberry Pi system.  Often these systems include USB ports, so the combination makes sense.


Our libraries are installed by building from source, and their main dependency is the {{Code|libusb-1.0-0-dev}} library, so if you can get gcc on your machine (or set up a cross compiler for it) and you can also install the libusb-1.0 development headers, you can probably get Phidgets to work.  Of course, we don't offer much support for these systems, so - depending on your system - expect to spend some raw time getting it up and going.
==Older Versions==
If you need older versions of the Phidget22 Linux libraries, [{{SERVER}}/downloads/phidget22/libraries/linux/libphidget22/ click here].


If you're new to the embedded computer thing, keep in mind that for these super basic systems, once you've gotten a power supply, and storage, and put the kernel you want on it, and then spent a couple of days of time getting things working, and  more time getting your drivers going, costs add up pretty quickly.  If you want a compact system that works right out of the box (and which can use all of our analog sensors in addition to our USB Phidgets), check out our [{{SERVER}}/products.php?product_id=1073 Single Board Computer].  Our SBC3:
If you need Phidget21 Linux Libraries, [{{SERVER}}/downloads/phidget21/libraries/linux/libphidget/ click here].
* Has many more USB ports than super-stripped devices, and also has digital and analog ports
* Includes a power supply and can run on batteries easily
* Has a nice amount of RAM, a decent embedded processor, and built-in onboard storage (we've run R, GRASS, and X11 on it)
* Includes installed Debian, working Phidget drivers, and [[Phidget Network Server|networked Phidget drivers]] from the moment it ships
* Has access to the full Debian repository including Python, Mono .NET, Ruby, and gcc
* Has a kernel development kit with patch file and instructions for adding new drivers (bluetooth, wireless, and so on)
* Comes with very in-depth documentation and technical support by phone and email
* Etc, etc.
The [[Phidget Network Server|networked support]] in particular allows it to work with your cell phone and more.


But if you really do want a raw hobbyist system to tinker with, go for it!  We're all nerds here - we've been there too and we certainly understand!
==Software License==
By downloading Linux Source you agree to adhere to the terms of the [https://opensource.org/licenses/BSD-3-Clause The 3-Clause BSD License].

Latest revision as of 18:28, 20 January 2025


Getting Started with Linux

Welcome to using Phidgets with Linux!

Install

The first step to using Phidgets with Linux is installing the Phidget22 libraries.

We provide prebuilt packages for Debian, Ubuntu, and their derivatives.

If you're running a supported distros, we recommend using the Package Install. For other systems, you can use the Source Install.

We recommend installing with our Install Script. If you prefer not to run a script, or the script cannot detect your distro, use the Manual Install.

To run the install script and install phidget22, enter the following command in the terminal: 

curl -fsSL https://www.phidgets.com/downloads/setup_linux | bash -
apt install -y libphidget22


curl -fsSL https://www.phidgets.com/downloads/setup_linux | sudo -E bash -
sudo apt install -y libphidget22

If the curl command is not found: apt install curl and try again.

To install our package repository manually, enter the following command in the terminal, replacing distro with your distro codename:

We support Debian releases from 6 to current, and Ubuntu LTS releases from 14.04 to current. If you are using another flavour of Linux (such as Mint), which is based on Ubuntu or Debian, use the corresponding Ubuntu or Debian codename.

Update your package lists: 

apt update


sudo apt update

Finally, install the Phidget package by entering the command below: 

apt install libphidget22


sudo apt install libphidget22

Additional Packages

You may also want to apt install the following optional packages:

  • libphidget22-dev: The C development libraries for Phidget22
  • libphidget22extra: Extra runtime library required for the Network Server and Admin tools
  • phidget22networkserver: The Phidget Network Server, which enables use of Phidgets over your network
  • libphidget22java: The Java libraries for Phidget22
  • phidget22admin: An administrator utility for listing Phidgets and upgrading firmware
  • phidget22wwwjs: The JavaScript libraries for Phidget22. This package also installs the HTML examples which can be accessed through the web interface


The libraries are now installed on your machine. Next, set up the UDev rules below.

Source Install

To install our libraries, first install libusb-1.0 development libraries. The exact command and package name will vary depending on distribution. For Debian based distributions, including Ubuntu and Mint, the command would be: 

apt install libusb-1.0-0-dev


Next, download and unpack the following files:

Open the README file that is included at the top of each directory. This file will give you important information about how to properly install the files.


Libraries are installed in /usr/local/lib by default. If you run into trouble finding the libraries during linking or at runtime, this probably means that /usr/local/lib is not on the library path for your distribution.

You can handle this in a number of ways:

Specify a different install folder during compile 

./configure --prefix=/usr && make && sudo make install

OR Add /usr/local/lib to the system-wide library path 

echo /usr/local/lib >> /etc/ld.so.conf && sudo ldconfig

OR Add /usr/local/lib in your local shell every time 

export LD_LIBRARY_PATH=$LD_LIBRARY_PATH:/usr/local/lib

The libraries are now installed on your machine. Next, you should set the UDev Rules.

Setting UDev Rules

By default, Linux will not grant permission to regular users to access physical hardware as a security feature. This means that in order to run Phidgets code from user space you must grant yourself root privileges via sudo. For example:

sudo ./HelloWorld

You can grant access manually or, more commonly, set up a rules file to do it automatically keying off of the vendor code for Phidget USB devices. To do this, create a text file called "99-libphidget22.rules" with the following contents: 

# All current and future Phidgets - Vendor = 0x06c2, Product = 0x0030 - 0x00af
SUBSYSTEMS=="usb", ACTION=="add", ATTRS{idVendor}=="06c2", ATTRS{idProduct}=="00[3-a][0-f]", MODE="666"

Where mode 666 means every user has permission to read and write to the specified file/device. You need to then move this file to "/etc/udev/rules.d". Now you can run Phidget related code as a regular user without the OS denying permission.

Verify

The best way to verify that your libraries are working properly is to compile and run an example program.


First, download and unpack this C example:

Note: If using the Debian intallation methods, you will need to install the libphidget22-dev package to use the C libraries for Phidget22

Next, open the terminal at the example location. Compile the example by entering the following command: 

 gcc HelloWorld.c -o HelloWorld -lphidget22


Run the HelloWorld example: 

./HelloWorld


Your terminal should look something like this:

Linux helloworld.PNG


The HelloWorld program will simply communicate when a Phidget has been attached or detached, as can be seen in the image above.


Your Phidget is now able to communicate with your development machine. The next step is selecting a programming language so you can start to write some code!

Programming

Ready to write some code? Select one of the programming languages below:

C C# Python Java JavaScript
C C# Python Java JavaScript
Swift Obj-C VB LabVIEW Max
Swift Obj-C VB LabVIEW Max
C C
C# C#
Python Python
Java Java
JavaScript JavaScript
Swift Swift
Objective C Objective C
VB VB
LabVIEW LabVIEW
Max Max

Older Versions

If you need older versions of the Phidget22 Linux libraries, click here.

If you need Phidget21 Linux Libraries, click here.

Software License

By downloading Linux Source you agree to adhere to the terms of the The 3-Clause BSD License.

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