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<metadesc>Communicate over USB with sensors, controllers and relays with Phidgets! Our Max/MSP library supports Windows and MacOS.</metadesc>
[[Category:Language]]
[[Category:Language]]
{{OSLang|[[File:icon-MaxMSP.png|link=|left|alt=MaxMSP|64x64px]]|Max/MSP, developed by [http://cycling74.com Cycling74] is a visual programming language for creating music and media applications.}}
__NOTOC__
__TOC__
We provide support for Max/MSP in '''macOS''' and '''Windows'''. We also provide instructions on how to get your project started. Select your operating system below, and follow the instructions to get your project running with Phidgets.


== Introduction ==
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.


If this is your first time working with a Phidget, we suggest starting with the Getting Started page for your specific device. This can be found in the user guide for your device. That page will walk you through installing drivers and libraries for your operating system, and will then bring you back here to use Max/MSP specifically.
==Setup Guide==
Max/MSP is capable of using the complete {{Phidget22API}}, including events. We also provide example code in Max/MSP for all Phidget devices.


Max/MSP is capable of using most of the Phidget API, including events. All the supported functions for Max/MSP will be documented in the .maxhelp files. We also provide example code in Max/MSP for all Phidget devices.
<div class="phd-deck-sequence">
{{PT3_MAX_CHOOSE}}{{PT3_MAX_WIN}}{{PT3_MAX_MAC}}
</div>


Max/MSP can be developed with Windows and OS X.
'''Only Max/MSP 6 and higher are supported.'''
You can compare Max/MSP with our other supported languages.


== Quick Downloads ==
== Quick Downloads ==
 
If you already know what you're doing and just need the files, you can find them all below.
'''<span style="color:#FF0000">List of download links, to be added once files are available</span>'''


=== Documentation ===
=== Documentation ===
=== Example Code ===
=== Libraries and Drivers ===
== Getting Started with Max/MSP ==
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(XP/Vista/7)|Windows XP / Vista / 7]]
*[[#OS X |OS X]]
== Windows ==
===Description of Library Files===
Max/MSP programs on Windows depend on the following files. The installers in the Quick Downloads section put only the phidget22.dll into your system. You will need to manually put the PhidgetXXX.mxe onto your system.
*'''phidget22.dll''' contains the actual Phidget library, which is used at run-time. By default, the installer places it in C:\Windows\System32.
*'''PhidgetXXX.mxe''' is the Phidget library for your specific device. XXX denotes the name of your device. Please make sure the .mxe file corresponds with the device you are using. For example, if you are using a PhidgetDigitalInput, you will need the PhidgetDigitalInput.mxe. It is to be placed in the same directory as your Max/MSP application or anywhere in the Max/MSP search path.
If you do not want to use our installer, you can download the phidget22.dll and manually install it where you want; refer to our [[Manual Installation Instructions]].
===Use Our Examples===
Please start by downloading the [[Max/MSP Examples and Library]] and unpack them into a folder. These examples were written in Max/MSP 6, but any version above 6 is also supported.
Here, you will find example programs, in .maxhelp format for all the devices. The source file will be named the same as the software object for your device. If you are not sure what the software object for your device is, find your Phidget on our [http://www.phidgets.com webpage], and then check the {{Phidget22API}} documentation for it.
The only thing left to do is to run the examples! Open the .maxhelp file in the Max environment.
Once you have the Max/MSP examples running, we have a [[#Edit 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 the Max/MSP environment to properly link the Phidget Max/MSP libraries. To begin:
Place the .mxe in the same directory as the patcher, or anywhere in the Max/MSP search path. You can verify the search path locations by navigating to Options → File Preferences.
[[Image: MaxMSP_File_Preferences_PC.png|500px]]
The best way to start writing your patch is to modify an example, and saving it as a .maxpat file.
If you wish to start a new patch. All you need to do is create an object named PhidgetXXX where XXX is the name of your device. For example, the PhidgetRFID device will have the PhidgetRFID object name. The project now has access to the Phidget function calls and you are ready to begin coding.
The same [[#Edit the Examples|teaching section]] which describes the examples also has further resources for programming your Phidget.
==OS X==
Max/MSP has excellent support on OS X.
The first step in using Max/MSP on Mac is to install the Phidget library. Compile and install as described on the OS - OS X page, which also describes the different Phidget files, their installed locations, and their roles.
===Use Our Examples===
Please start by downloading the Max/MSP Examples and Library and unpack them into a folder. These examples were written in Max/MSP 6, but any version above 6 is also supported.
Here, you will find example programs, in .help format for all the devices. The source file will be named the same as the software object for your device. If you are not sure what the software object for your device is, find your Phidget on our [http://www.phidgets.com webpage], and then check the {{Phidget22API}} documentation for it.
The only thing left to do is to run the examples! Open the .maxhelp file in the Max environment.
Once you have the Max/MSP examples running, we have a [[#Edit 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 the Max/MSP environment to properly link the Phidget Max/MSP libraries. To begin:
Place the .mxe in the same directory as the patcher, or anywhere in the Max/MSP search path. You can verify the search path locations by navigating to Options → File Preferences.
[[Image: MaxMSP_File_Preferences_OSX.png|600px]]
The best way to start writing your patch is to modify an example, and saving it as a .pat file.
If you wish to start a new patch. All you need to do is create an object named PhidgetXXX where XXX is the name of your device. For example, the PhidgetRFID device will have the PhidgetRFID object name. The project now has access to the Phidget function calls and you are ready to begin coding.
The same [[#Edit the Examples|teaching section]] which describes the examples also has further resources for programming your Phidget.
== Edit 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 Max/MSP code will be the {{Phidget22API}} Manual:
=== Example Flow ===
First, let's explain how to operate the example.
[[Image: MSP Example.png|500px]]
The above screenshot is what shows up when you open the example for the PhidgetVoltageInput. If you are using a different device, your example patch will be different, but the idea is the same.
For this particular example, the Max object is called PhidgetVoltageInput, which is located near the bottom left of the screen. Objects/message boxes are connected to the inputs and outputs of the PhidgetVoltageInput object. The input objects will either cause a property of the device to change or request for a property to be retrieved. The output objects return the retrieved information. All the supported features of the device are shown in the .maxhelp file.
Try it for yourself! Click on the getSerial message box to request the Phidget to retrieve the serial number of the device. You should see the last output object of route changed to the serial number of your device. All devices support the getSerial object, and is the easiest way to determine if the Phidget libraries are correctly set up, and whether the Max/MSP application is connected to your device.
[[Image: MaxMSP_GetSerial.png]]
If your example contains the read message box, click on it. This will return device specific values to the screen.
[[Image: MaxMSP_Read.png|500px]]
If your example contains the start message box, you can continuously poll for events. Set the sample rate input for the setDataInterval object. Then, press the start message box to start sampling. When a noteworthy event occurs on a Phidget(i.e., when a sensor senses a change in the environment), the value will be displayed onto the screen. Press the stop message box to stop sampling.
For the PhidgetDigitalOutput example, there are setDutyCycle and setState message boxes. Changing the numbers will cause the digital output to change. Your example may contain device specific message boxes/objects to click on. See for yourself what they do!
For information regarding calls specific to your device, please see the {{Phidget22API}} for your specific device, which can be found in its user guide. Please note that some device functionality are not supported in Max/MSP; the .maxhelp example shows the complete list of functionality supported under Max/MSP.
=== Code Snippets ===
Your best resource to program code .help files in MaxMSP will be our examples. The examples are both our complete API (they include all of the calls for each Phidget you can use, and none you can't) and examples of how to use our API.
If you aren't familiar with concepts in Phidget programming, you may find our General Phidget Programming page helpful. It provides a very generic overview of what traditional languages follow when using Phidgets. For setup 'syntax', your main resource will of course be this MaxMSP page and the examples. But for conceptual details about particular actions - opening a Phidget, for example - the General Phidget Programming page is a more in-depth resource.
Keep in mind when reading these general resources that the Max/MSP libraries may not implement the full {{Phidget22API}} - some function calls and Phidget classes may not be supported. The .maxhelp files included with the Phidget externals show all the supported function calls for their type of Phidget.
In general, Phidgets can be placed inside the patcher using Max objects, and functions can be called on them using appropriately connected messages. We go over a basic setup for this below.
==== Step One: Initialize and Open ====
This tutorial uses a Phidget Interface Kit and a new instance will be created. This initializing and opening can be done by placing a new "object" object. Other objects can handle different Phidgets - a Spatial, a Temperature Sensor, a Motor Controller, etc. Only the name of the object changes. You can find the name in the example .maxhelp file for your device. The source file will be named the same as the software object for your device. If you are not sure what the software object for your device is, find your Phidget on our [http://www.phidgets.com webpage], and then check the API documentation for it.
In the case of a Voltage Input, we name it PhidgetVoltageInput:
[[Image: MaxMSP_VoltageInput_generic.png]]
'''Important:''' a local connection will reserve the device until closed. This prevents any other instances from retrieving data from the Phidget, including other programs. Every Phidget object in Max will automatically try to connect to and reserve the Phidget for itself. As long as a MaxMSP Phidget program is running, it will continuously try to connect to a Phidget, even trying to reconnect if it gets disconnected.
When the instance is created as with the Voltage Input above, normally it will make a connection to the first device of its type it can find. The Phidget object can also be declared with a serial number to open a specific Phidget Voltage Input instead:
[[Image: MaxMSP VoltageInput specific.png]]
=====Using a Phidget Over a Network=====
To use the Network Service, first the Phidget needs to be plugged in to a computer that has the Network  Service turned on within your local network. (For information on how to do this, see the Phidget Network Service page in the section on how to use the Network Service for your operating system). Then, in MaxMSP, we can change the open "object" text for various types of opening over a network. Many examples are given below.
Open any remote Digital Input on a network visible by MDNS:
{{Code|PhidgetDigitalInput remote}}
Open a remote Digital Input with serial number 35569, on any remote server
{{Code|PhidgetDigitalInput 35569 remote}}
'''NOTE:''' the following examples are only necessary for a network that cannot be connected to using MDNS
Open a remote Digital Input on server "James PC" with an IP address and port:
{{Code|PhidgetDigitalInput remote AF_INET "James PC" 192.168.2.5 5661}}
Open a remote Digital Input on server "James PC" on host "James-PC" port 5661 with password "pass":
{{Code|PhidgetDigitalInput remote AF_INET "James PC" "James-PC" 5661 "pass"}}
==== Step Two: Wait for Attachment (plugging in) of the Phidget ====
Although this is a required step in many of our other languages (and therefore you may be expecting this if coming from another Phidget language), in MaxMSP you do not have to add a specific waitForAttachment block.
Keep in mind, however, that if your Phidget is not responding within your MaxMSP program, it may simply not be plugged in!
==== Step Three: Do Things with the Phidget ====
There are two main approaches for retrieving data when working with Phidgets. Data is accessed either by one-time polling, or at a fixed rate via on-board timers for some devices.
Getting or setting values directly via polling on the Phidget is done through messages linked to the inlet. The object’s inlet can be wired to send commands to the device, and the outlet used to retrieve the results. Setting values on the Phidget is achieved by using the set messages, and some properties can be read with get messages:
[[Image: MaxMSP_get_and_set.png]]
For data, polling occurs through the "read" message. To sample at a fixed rate you use setDataInterval and use the start and stop message. Read will read the data off the Phidget once, while using start will trigger data to be sent or received in periodic intervals. If the sample rate is set to -1, then data output is only triggered on a change:
[[Image: MaxMSP_Read_Start_Stop.png]]
Phidget-specific data is always given a prefix in Max to allow for their routing. For instance, the digital input states are given the prefix “di” and the voltage ratio inputs similarly use “vr”. The specific prefixes used for each Phidget is listed in their respective help file.
Data common to all Phidgets, such as the serial number, is not prefixed.
With the prefixes and common data, the following picture would be an example of how to route and split some of the data for the PhidgetAccelerometer:
[[Image: MaxMSP_Routing.png]]
==== Step Four: Close and Delete ====
Although this is a required step in many of our other languages (and therefore you may be expecting this if coming from another Phidget language), in MaxMSP you do not have to add a specific close and delete block.
====Special Case: Multiple Phidgets====
Multiple Phidgets of the same type can easily be used inside a single program, it only requires another Phidget object placed. If two of the same type of Phidget object are placed, the serial number and channel arguments should always be specified (as well as hub port, if applicable) to ensure that the correct Phidget gets associated with the correct object.
== 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.


[[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.
*{{Phidget22API}} (Select Max/MSP from drop-down menu)


[[Logging, Exceptions, and Errors]] - Learn about all the tools you can use to debug your program.
=== Phidgets Max Libraries ===


[[Phidget Network Service]] - Phidgets can be controlled and communicated with over your network- either wirelessly or over ethernet.
* [https://cdn.phidgets.com/downloads/phidget22/libraries/windows/Phidget22MaxMSP.zip Windows Max Libraries for Phidgets]
* [https://cdn.phidgets.com/downloads/phidget22/libraries/macos/Phidget22MaxMSP.zip MacOS Max Libraries for Phidgets]


== Common Problems and Solutions/Workarounds ==
=== Max Example Code ===


'''Crash: <span style="color:DarkRed">When a patch file is closed in the Max/MSP environment, the program crashes</span>'''
*{{SampleCode|MaxMSP|Max/MSP Example}}


If in your Max/MSP environment, you have more patches(of the same Phidget object) than you have of the actual hardware device, the Max/MSP environment may crash. This is due to the fact that a single Phidget Max/MSP object only corresponds to a single Phidget device hardware. For example, your Max/MSP environment may experience unexpected behavior while you have one PhidgetInterfaceKit device connected to the computer, but you have a two seperate patches opened with a single PhidgetInterfaceKit Max object in each one.
===Phidgets Core Libraries===


Likely Fix: Please ensure that you do not use more patches(of the same Phidget object) than you have of the actual Phidget device.
{{AllQuickDownloads}}

Latest revision as of 18:18, 20 February 2024


We provide support for Max/MSP in macOS and Windows. We also provide instructions on how to get your project started. Select your operating system below, and follow the instructions to get your project running with Phidgets.

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.

Setup Guide

Max/MSP - Select Development Environment

Select your Development Environment:

Windows

macOS

Language - Max/MSP

Windows with Max/MSP

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

Phidget22 supports Max/MSP versions 6 and up.

Requirements

First, make sure you have the following installed:

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

Max/MSP

Use Our Examples

Next, download and unpack the Phidgets Max/MSP library:

Phidget Max/MSP library

Use Our Examples

After unpacking the download, navigate to the externals folder. Copy the following folder to your clipboard:

  • For 32-bit Max/MSP, copy the x86 folder
  • For 64-bit Max/MSP, copy the x64 folder

Use Our Examples

The folder you copied needs to be placed in a specific location for Max/MSP to reference it. Open Max/MSP and navigate to Options -> File Preferences.

Use Our Examples

The folder that you copied earlier needs to be placed in any of the locations listed in File Preferences. Navigate to one of the locations and paste the folder:

Use Our Examples

The Phidget Max/MSP library is now being referenced. Next, navigate to the examples folder located within the Phidget22MaxMSP folder you previously unpacked:

Use Our Examples

From here, select an example that will work with your Phidget and open it in Max/MSP. You can run the example by simply pressing the start button:

The example is now running. Play around with the device and experiment with some of the functionality. When you are ready, the next step is configuring your project and writing your own code!

Write Code

You should now have working examples and a project that is configured. This teaching section will help you understand how the examples were written so you can start writing your own code.

Remember: your main reference for writing Max/MSP code will be:

● The Phidget22 API Manual

● The Max/MSP examples

Write Code

First, let's explain how to operate the examples. We will take a look at the PhidgetVoltageInput example:

For this particular example, the Max object is called PhidgetVoltageInput. Objects/message boxes are connected to the inputs and outputs of this object. Input objects will either cause a property of the device to change or request for a property to be retrieved. Output objects return the retrieved information.

All supported functions for Max/MSP can be found in the Phidget22 API.

Write Code

Try it for yourself! Click on the getDeviceSerialNumber message box to request the Phidget to retrieve the serial number of the device. You should see the a message in the Max window denoting the serial number of your device. All devices support the getDeviceSerialNumber message, making it an easy way to determine if the Phidget libraries are correctly set up, and whether the Max/MSP application is connected to your device.

If your example contains a get[DataType] message box (e.g. getVoltage), click on it to cause the associated data to be output with a relevant prefix. [DataType] can be data member the object has. A list of available messages and their associated outputs is outlined in the Phidget22 API for your device.

Write Code

If your example contains the start message box, you can continuously poll for events. Just press the start message box to start sampling. When an event occurs on a Phidget (i.e. when a sensor detects a change in the measured data), associated data will be output with related prefixes. Press the stop message box to stop sampling.

For the PhidgetDigitalOutput example, there are setDutyCycle and setState message boxes. Changing the numbers will cause the digital output to change. Your example may contain device specific message boxes to click on. Click them to see what they do!

Write Code

Your best resource to program in MaxMSP will be our examples. If you aren't familiar with concepts in Phidget programming, you may find our Phidget Programming Basics page helpful. It provides a very generic overview of what traditional languages follow when using Phidgets. For Max users, conceptual details about particular actions (e.g. opening a Phidget) are explained there.

Keep in mind when reading these general resources that the Max/MSP libraries may not implement the full Phidgets API - some function calls and Phidget classes may not be supported.

In general, Phidget objects can be placed inside the patcher, and functions can be called on them using appropriately connected messages. We'll go over a basic setup next.

Write Code

Step One: Initialize and Open

Initializing and opening the device is be done by placing a new object. Other objects handle different Phidgets - a Spatial, a Light Sensor, a Motor Controller, etc. Only the name of the object changes. You can find the name for the object in the device's .maxhelp file (e.g. VoltageInput.maxhelp). If you are unsure what the software object for your device is, go to the API tab on its product page on our website.

In the case of a Voltage Input, we name it PhidgetVoltageInput:

Important: a local connection will reserve the device until closed. This prevents any other instances from retrieving data from the Phidget, including other programs. Every Phidget object in Max will automatically try to connect to and reserve a Phidget for itself. As long as a MaxMSP Phidget object is running, it will continuously try to connect to a Phidget, even trying to reconnect if it gets disconnected.

Write Code

Specifying a Phidget

When the instance is created as with the Voltage Input above, normally it will make a connection to the first device of its type it can find. The Phidget object can also be declared with a number of specifiers to open a specific Phidget instead.

Specifiers can be added to the object in the format: PhidgetExternal {Specifiers}. These will be written in the form: specifier=value

The full list of specifiers that can be used to identify a Phidget in Max/MSP are as follows:

  • serialnumber - The serial number of the device
  • channel - The channel of the device to open
  • hubport - The hub port the device is plugged into (where applicable)
  • ishubport - Specifies whether this channel should be opened on a hub port directly, or on a VINT device attached to a hub port.
  • remote - Forces connection to a remote device over a network, ignoring devices on the local machine
  • local - Forces connection to a device plugged into the local machine, ignoring network devices

Write Code

Specifying a Phidget

For instance, to open a VoltageInput with serial number 349428, you would use:

Some other examples:

Open a Digital Input:

PhidgetDigitalInput

Open channel 1 of a Digital Input Phidget connected to port 2 of a hub with serial number 35569

PhidgetDigitalInput serialnumber=35569 channel=1 hubport=2

Open open hub port 2 as a DigitalInput for a hub with serial number 35569

PhidgetDigitalInput serialnumber=35569 hubport=2 ishubport=1

Write Code

Using a Phidget Over a Network

To use the Network Server, first the Phidget needs to be plugged in to a computer that has the Network Server turned on within your local network. (For information on how to do this, see the Phidget Network Server page in the section on how to use the Network Server for your operating system).

Next, in your patch you need a PhidgetNet object. To automatically find local networks, send it a message saying enableServerDiscovery.

Then, to connect a Phidget over the network, change the object text to specify it is to connect to a Phidget on a remote server, as per the following example.

Write Code

Step Two: Wait for Attachment (plugging in) of the Phidget

Although this is a required step in many of our other languages (and therefore you may be expecting this if coming from another Phidget language), in MaxMSP you do not have to add a specific waitForAttachment block.

Keep in mind, however, that if your Phidget is not responding within your MaxMSP program, it may simply not be plugged in! Send a getAttached message to a Phidget object at any time to see if it's attached.

Write Code

Step Three: Do Things with the Phidget

Phidget data is accessed either by one-time polling or at a fixed rate via on-board timers for some devices.

Getting or setting values directly via polling on the Phidget is done through messages linked to the inlet. The object’s inlet can be wired to send commands to the device, and the outlet used to retrieve the results. You can set values on the Phidget by using the set messages, and some properties can be read with get messages:

To sample at a fixed rate, use the start and stop messages to start and stop the data flow, respectively.

Write Code

Step Three: Do Things with the Phidget

Outlet data is always given a prefix to allow for routing. For instance, the digital input state state change event data is given the prefix stateChange, and the voltage input voltage change event similarly use voltageChange. The specific prefixes for each set of outlet data is listed on the API page for that class.

The rightmost outlet on the Phidget object outputs error event data. This will send information on error events such as saturation events. To see which error events may apply to your device, check its API page.

Write Code

Step Four: Close and Delete

Although this is a required step in many of our other languages (and therefore you may be expecting this if coming from another Phidget language), in MaxMSP you do not have to add a specific close and delete block.

Special Case: Multiple Phidgets

Multiple Phidgets of the same type can easily be used inside a single program, it only requires another Phidget object placed. If two of the same type of Phidget object are placed, the serial number and channel arguments should always be specified (as well as hub port, if applicable) to ensure that the correct Phidget gets associated with the correct object.

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 - Max/MSP

MacOS with Max/MSP

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

Phidget22 supports Max/MSP versions 6 and up.

Requirements

First, make sure you have the following installed:

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

Max/MSP

Use Our Examples

Next, download and unpack the Phidgets Max/MSP library:

Phidget Max/MSP library

Use Our Examples

After unpacking the download, navigate to the externals folder and copy it to your clipboard:

Use Our Examples

The folder you copied needs to be placed in a specific location for Max/MSP to reference it. Open Max/MSP and navigate to Options -> File Preferences.

You will see something similar to this:

Use Our Examples

The folder that you copied earlier needs to be placed in any of the locations listed in File Preferences. Navigate to one of the locations and paste the folder:

Use Our Examples

The Phidget Max/MSP library is now being referenced. Next, navigate to the examples folder located within the Phidget22MaxMSP folder you previously unpacked:

Use Our Examples

From here, select an example that will work with your Phidget and open it in Max/MSP. You can run the example by simply pressing the start button:

The example is now running. Play around with the device and experiment with some of the functionality. When you are ready, the next step is configuring your project and writing your own code!

Write Code

You should now have working examples and a project that is configured. This teaching section will help you understand how the examples were written so you can start writing your own code.

Remember: your main reference for writing Max/MSP code will be:

● The Phidget22 API Manual

● The Max/MSP examples

Write Code

First, let's explain how to operate the examples. We will take a look at the PhidgetVoltageInput example:

For this particular example, the Max object is called PhidgetVoltageInput. Objects/message boxes are connected to the inputs and outputs of this object. Input objects will either cause a property of the device to change or request for a property to be retrieved. Output objects return the retrieved information.

All supported functions for Max/MSP can be found in the Phidget22 API.

Write Code

Try it for yourself! Click on the getDeviceSerialNumber message box to request the Phidget to retrieve the serial number of the device. You should see the a message in the Max window denoting the serial number of your device. All devices support the getDeviceSerialNumber message, making it an easy way to determine if the Phidget libraries are correctly set up, and whether the Max/MSP application is connected to your device.

If your example contains a get[DataType] message box (e.g. getVoltage), click on it to cause the associated data to be output with a relevant prefix. [DataType] can be data member the object has. A list of available messages and their associated outputs is outlined in the Phidget22 API for your device.

Write Code

If your example contains the start message box, you can continuously poll for events. Just press the start message box to start sampling. When an event occurs on a Phidget (i.e. when a sensor detects a change in the measured data), associated data will be output with related prefixes. Press the stop message box to stop sampling.

For the PhidgetDigitalOutput example, there are setDutyCycle and setState message boxes. Changing the numbers will cause the digital output to change. Your example may contain device specific message boxes to click on. Click them to see what they do!

Write Code

Your best resource to program in MaxMSP will be our examples. If you aren't familiar with concepts in Phidget programming, you may find our Phidget Programming Basics page helpful. It provides a very generic overview of what traditional languages follow when using Phidgets. For Max users, conceptual details about particular actions (e.g. opening a Phidget) are explained there.

Keep in mind when reading these general resources that the Max/MSP libraries may not implement the full Phidgets API - some function calls and Phidget classes may not be supported.

In general, Phidget objects can be placed inside the patcher, and functions can be called on them using appropriately connected messages. We'll go over a basic setup next.

Write Code

Step One: Initialize and Open

Initializing and opening the device is be done by placing a new object. Other objects handle different Phidgets - a Spatial, a Light Sensor, a Motor Controller, etc. Only the name of the object changes. You can find the name for the object in the device's .maxhelp file (e.g. VoltageInput.maxhelp). If you are unsure what the software object for your device is, go to the API tab on its product page on our website.

In the case of a Voltage Input, we name it PhidgetVoltageInput:

Important: a local connection will reserve the device until closed. This prevents any other instances from retrieving data from the Phidget, including other programs. Every Phidget object in Max will automatically try to connect to and reserve a Phidget for itself. As long as a MaxMSP Phidget object is running, it will continuously try to connect to a Phidget, even trying to reconnect if it gets disconnected.

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Specifying a Phidget

When the instance is created as with the Voltage Input above, normally it will make a connection to the first device of its type it can find. The Phidget object can also be declared with a number of specifiers to open a specific Phidget instead.

Specifiers can be added to the object in the format: PhidgetExternal {Specifiers}. These will be written in the form: specifier=value

The full list of specifiers that can be used to identify a Phidget in Max/MSP are as follows:

  • serialnumber - The serial number of the device
  • channel - The channel of the device to open
  • hubport - The hub port the device is plugged into (where applicable)
  • ishubport - Specifies whether this channel should be opened on a hub port directly, or on a VINT device attached to a hub port.
  • remote - Forces connection to a remote device over a network, ignoring devices on the local machine
  • local - Forces connection to a device plugged into the local machine, ignoring network devices

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Specifying a Phidget

For instance, to open a VoltageInput with serial number 349428, you would use:

Some other examples:

Open a Digital Input:

PhidgetDigitalInput

Open channel 1 of a Digital Input Phidget connected to port 2 of a hub with serial number 35569

PhidgetDigitalInput serialnumber=35569 channel=1 hubport=2

Open open hub port 2 as a DigitalInput for a hub with serial number 35569

PhidgetDigitalInput serialnumber=35569 hubport=2 ishubport=1

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Using a Phidget Over a Network

To use the Network Server, first the Phidget needs to be plugged in to a computer that has the Network Server turned on within your local network. (For information on how to do this, see the Phidget Network Server page in the section on how to use the Network Server for your operating system).

Next, in your patch you need a PhidgetNet object. To automatically find local networks, send it a message saying enableServerDiscovery.

Then, to connect a Phidget over the network, change the object text to specify it is to connect to a Phidget on a remote server, as per the following example.

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Step Two: Wait for Attachment (plugging in) of the Phidget

Although this is a required step in many of our other languages (and therefore you may be expecting this if coming from another Phidget language), in MaxMSP you do not have to add a specific waitForAttachment block.

Keep in mind, however, that if your Phidget is not responding within your MaxMSP program, it may simply not be plugged in! Send a getAttached message to a Phidget object at any time to see if it's attached.

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Step Three: Do Things with the Phidget

Phidget data is accessed either by one-time polling or at a fixed rate via on-board timers for some devices.

Getting or setting values directly via polling on the Phidget is done through messages linked to the inlet. The object’s inlet can be wired to send commands to the device, and the outlet used to retrieve the results. You can set values on the Phidget by using the set messages, and some properties can be read with get messages:

To sample at a fixed rate, use the start and stop messages to start and stop the data flow, respectively.

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Step Three: Do Things with the Phidget

Outlet data is always given a prefix to allow for routing. For instance, the digital input state state change event data is given the prefix stateChange, and the voltage input voltage change event similarly use voltageChange. The specific prefixes for each set of outlet data is listed on the API page for that class.

The rightmost outlet on the Phidget object outputs error event data. This will send information on error events such as saturation events. To see which error events may apply to your device, check its API page.

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Step Four: Close and Delete

Although this is a required step in many of our other languages (and therefore you may be expecting this if coming from another Phidget language), in MaxMSP you do not have to add a specific close and delete block.

Special Case: Multiple Phidgets

Multiple Phidgets of the same type can easily be used inside a single program, it only requires another Phidget object placed. If two of the same type of Phidget object are placed, the serial number and channel arguments should always be specified (as well as hub port, if applicable) to ensure that the correct Phidget gets associated with the correct object.

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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