mexHIDUsage Class Reference

Overview

Look up names and values for working with Human Interface Devices.

HID is a general-purpose specification for how to communicate with Himan Interface Devices. Part of the HID specification provides numeric "usage" and "type" values that devices can report about themselves to an operating system or program (like Matlab and mexHID()). These values are not obvious, for example 2 might mean "Input_Button" or "Simulation", and 6 might mean "Keyboard".

mexHIDUsage() attempts to make these meanings clearer. It provides static methods that map the numeric usage values to human-readable string names. There are a few different types of mapping:

• nameForPageNumber() and numberForPageName() address usage "pages". A usage page is group of related usage values. "Generic_Desktop" and "Simulation" are examples of usage page names.
• nameForUsageNumberOnPage() and numberForUsageNameOnPage() address individual usage values, within the scope of a single usage page. "Joystick" and "KeyboardLeftShift" are examples of individual usages from different pages.
• nameForElementTypeNumber() and numberForElementTypeName() address type values (which are different from usage values) that describe parts of a device. "Input_Button" and "Output" are examples of element types.

The mexHIDUsage.gui() method opens a figure which summarizes all of the HID usage pages and individual usages by name and number.

The mexHID() function, which actually interacts with HID devices requires numeric usage, page, and type values inorder to do things like find a device or device elements suitable for a given task. mexHIDUsage should make finding the correct values less mysterious.

During development, I (Ben Heasly) used the HID Usages contained in IOHIDUsageTables.h, which is part of the OS X UIKit framework, to build lookuptables. I also copied by hand the element type enum from IOHIDKeys.h. Users should not need to worry about this, since they can use the tables saved for Matlab in the mexHIDUsageMat file.

Inheritance diagram for mexHIDUsage:

Protected Properties
Property	pageNumberToName
	containers.Map of HID usage page number -> name
Property	pageNameToNumber
	containers.Map of HID usage page name -> number
Property	usageNumbersToNames
	Many containers.Map of HID usage number -> name, one for each usage page. More...
Property	usageNamesToNumbers
	Many containers.Map of HID usage name -> number, one for each usage page. More...
Property	elementTypeNameToNumber
	containers.Map of HID element type name -> number
Property	elementTypeNumberToName
	containers.Map of HID element type number -> name
Property	mexHIDUsageMat = 'mexHIDUsage.mat'
	Filename with path to .mat file containing mexHIDUsage data.
Property	pageEnum = 'kHIDPage_(\w+)\s=\s0x(\w+)'
	Regular expression to get a page declaration out of the topmost enum. More...
Property	pageUsageEnumFinder = 'Page\s\(0x(\w+)\)\s\*\/'
	Regular expression to get the enum for a particular usage page. More...
Property	usageEnum = 'kHIDUsage_([a-zA-Z]+)_(\w+)\s=\s0x(\w+)'
	Regular expression to get a usage declaration out of an enum. More...
Property	usageEnumNoAbr = 'kHIDUsage_(\w+)\s=\s0x(\w+)'
	Regular expression to get a usage declaration out of an enum when there is no Apple abbreviation. More...

Static Methods
static obj	theObject ()
	Access the current instance.
static	reset ()
	Reload page, usage, and type data.
static fig	gui ()
	Open a figure which summarizes usages and pages by name and number. More...

Private Methods
self	mexHIDUsage ()
	Constructor is private. More...

Constructor

mexHIDUsage()

self mexHIDUsage ( )

private

Constructor is private.

Use mexHIDUsage.theObject to access the current instance.

Methods

gui()

static fig gui ( )

static

Open a figure which summarizes usages and pages by name and number.

Properties and Events

usageNumbersToNames

Property usageNumbersToNames

protected

Many containers.Map of HID usage number -> name, one for each usage page.

Contained in a containers.Map with page number keys.

usageNamesToNumbers

Property usageNamesToNumbers

protected

Many containers.Map of HID usage name -> number, one for each usage page.

Contained in a containers.Map with page number keys.

pageEnum

Property pageEnum = 'kHIDPage_(\w+)\s=\s0x(\w+)'

protected

Regular expression to get a page declaration out of the topmost enum.

The tokens are:

• the page name
• the page number in hex

pageUsageEnumFinder

Property pageUsageEnumFinder = 'Page\s\(0x(\w+)\)\s\*\/'

protected

Regular expression to get the enum for a particular usage page.

The token is:

• the page number in hex

usageEnum

Property usageEnum = 'kHIDUsage_([a-zA-Z]+)_(\w+)\s=\s0x(\w+)'

protected

Regular expression to get a usage declaration out of an enum.

The tokens are:

• Apple's abbreviated usage page name
• the usage name
• the usage number in hex

usageEnumNoAbr

Property usageEnumNoAbr = 'kHIDUsage_(\w+)\s=\s0x(\w+)'

protected

Regular expression to get a usage declaration out of an enum when there is no Apple abbreviation.

The tokens are:

• the usage name
• the usage number in hex

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The documentation for this class was generated from the following file:

• mexHIDUsage.m