Docs: Adding Headset requirements and testing in new section
Adding in changes from b/21029010
Bug: 19231083
Bug: 21029010
Change-Id: I3cf4b9e6666d77a72374fe067cce06ceb950b2b2
diff --git a/src/accessories/accessories_toc.cs b/src/accessories/accessories_toc.cs
index 654ff7b..616cc5e 100644
--- a/src/accessories/accessories_toc.cs
+++ b/src/accessories/accessories_toc.cs
@@ -1,5 +1,5 @@
<!--
- Copyright 2014 The Android Open Source Project
+ Copyright 2015 The Android Open Source Project
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
@@ -30,9 +30,20 @@
</a>
</div>
<ul>
- <li><a href="<?cs var:toroot ?>accessories/headset-spec.html">Headset specification</a></li>
+ <li class="nav-section">
+ <div class="nav-section-header">
+ <a href="<?cs var:toroot ?>accessories/headset/index.html">
+ <span class="en">Headset</span>
+ </a>
+ </div>
+ <ul>
+ <li><a href="<?cs var:toroot ?>accessories/headset/specification.html">Specification</a></li>
+ <li><a href="<?cs var:toroot ?>accessories/headset/requirements.html">Requirements</a></li>
+ <li><a href="<?cs var:toroot ?>accessories/headset/testing.html">Testing</a></li>
</ul>
- </li>
+ </li>
+ </ul>
+ </li>
<li class="nav-section">
<div class="nav-section-header">
<a href="<?cs var:toroot ?>accessories/custom.html">
@@ -45,8 +56,8 @@
</a>
</div>
<ul>
- <li><a href="<?cs var:toroot ?>accessories/aoa2.html">Version 2.0</a></li>
- <li><a href="<?cs var:toroot ?>accessories/aoa.html">Version 1.0</a></li>
+ <li><a href="<?cs var:toroot ?>accessories/aoa2.html">AOA 2.0</a></li>
+ <li><a href="<?cs var:toroot ?>accessories/aoa.html">AOA 1.0</a></li>
</ul>
</li>
</ul>
diff --git a/src/accessories/aoa.jd b/src/accessories/aoa.jd
index 7388d54..7c728fe 100644
--- a/src/accessories/aoa.jd
+++ b/src/accessories/aoa.jd
@@ -2,7 +2,7 @@
@jd:body
<!--
- Copyright 2013 The Android Open Source Project
+ Copyright 2015 The Android Open Source Project
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
@@ -16,55 +16,81 @@
See the License for the specific language governing permissions and
limitations under the License.
-->
-<p>An Android USB accessory must adhere to Android Accessory Protocol, which defines how
-an accessory detects and sets up communication with an Android-powered device. In general, an
-accessory should carry out the following steps:</p>
+<p>Android USB accessories must adhere to the Android Open Accessory (AOA)
+protocol, which defines how an accessory detects and sets up communication with
+an Android-powered device. Accessories should carry out the following steps:</p>
+
<ul>
-<li>Wait for and detect connected devices</li>
-<li>Determine the device's accessory mode support</li>
-<li>Attempt to start the device in accessory mode if needed</li>
-<li>Establish communication with the device if it supports the Android accessory protocol</li>
+<li>Wait for and detect a connected device.</li>
+<li>Determine the device's accessory mode support.</li>
+<li>Attempt to start the device in accessory mode (if needed).</li>
+<li>If the device supports AOA, establish communication with the device.</li>
</ul>
+
<p>The following sections explain how to implement these steps.</p>
-<h2 id="wait-for-and-detect-connected-devices">Wait for and Detect Connected Devices</h2>
-<p>Your accessory should have logic to continuously check for connected Android-powered devices.
-When a device is connected, your accessory should determine if the device supports accessory mode.</p>
-<h2 id="determine-accessory-mode-support">Determine Accessory Mode Support</h2>
-<p>When an Android-powered device is connected, it can be in one of three states:</p>
+
+<p class="note">When developing a new accessory that connects to an Android
+device over USB, use <a href="{@docRoot}accessories/aoa2.html">AOAv2</a>.</p>
+
+<h2 id="wait-for-and-detect-connected-devices">Wait for and detect connected
+devices</h2>
+
+<p>Accessories should continuously check for connected Android-powered devices.
+When a device is connected, the accessory should determine if the device
+supports accessory mode.</p>
+
+<h2 id="determine-accessory-mode-support">Determine accessory mode support</h2>
+
+<p>When an Android-powered device connects, it can be in one of three states:
+</p>
+
<ul>
-<li>The attached device supports Android accessory mode and is already in accessory mode.</li>
-<li>The attached device supports Android accessory mode, but it is not in accessory mode.</li>
-<li>The attached device does not support Android accessory mode.</li>
+<li>Supports Android accessory mode and is already in accessory mode.</li>
+<li>Supports Android accessory mode but it is not in accessory mode.</li>
+<li>Does not support Android accessory mode.</li>
</ul>
-<p>During the initial connection, the accessory should check the vendor and product IDs of the
-connected device's USB device descriptor. The vendor ID should match Google's ID (<code>0x18D1</code>) and the
-product ID should be <code>0x2D00</code> or <code>0x2D01</code> if the device is already in accessory mode (case A). If
-so, the accessory can now
-<a href="#establish-communication-with-the-device">establish communication with the device</a> through
-bulk transfer endpoints with its own communication protocol. There is no need to start the device
-in accessory mode.</p>
-<p><strong>Note:</strong> <code>0x2D00</code> is reserved for Android-powered devices that
-support accessory mode. <code>0x2D01</code> is reserved for devices that support accessory mode as well as the
-ADB (Android Debug Bridge) protocol, which exposes a second interface with two bulk endpoints for
-ADB. You can use these endpoints for debugging the accessory application if you are simulating
-the accessory on a computer. In general, do not use this interface unless your accessory is
-implementing a passthrough to ADB on the device.</p>
-<p>If the vendor and product ID do not match, there is no way to distinguish between states b and c, so
-the accessory <a href="#attempt-to-start-in-accessory-mode">attempts to start the device in accessory mode</a>
-to determine if the device is supported.</p>
-<h2 id="attempt-to-start-in-accessory-mode">Attempt to Start in Accessory Mode</h2>
-<p>If the vendor and product IDs do not correspond to an Android-powered device in accessory
-mode, the accessory cannot discern whether the device supports accessory mode and is not in that
-state, or if the device does not support accessory mode at all. This is because devices that
-support accessory mode but aren't in it initially report the device's manufacturer vendor ID and
-product ID, and not the special Android Open Accessory ones. In either case, the accessory should
-try to start the device into accessory mode to figure out if the device supports it. The following
-steps explain how to do this:</p>
+
+<p>During the initial connection, the accessory should check the vendor ID and
+product ID of the connected device's USB device descriptor. The vendor ID
+should match Google's ID (<code>0x18D1</code>). If the device is already in
+accessory mode, the product ID should be <code>0x2D00</code> or
+<code>0x2D01</code> and the accessory can
+<a href="#establish-communication-with-the-device">establish communication with
+the device</a> through bulk transfer endpoints using its own communication
+protocol (the device does not need to be started in accessory mode).</p>
+
+<p class="note"><strong>Note:</strong> <code>0x2D00</code> is reserved for
+Android-powered devices that support accessory mode. <code>0x2D01</code> is
+reserved for devices that support accessory mode as well as the Android Debug
+Bridge (ADB) protocol, which exposes a second interface with two bulk endpoints
+for ADB. You can use these endpoints for debugging the accessory application if
+you are simulating the accessory on a computer. In general, do not use this
+interface unless the accessory implements a passthrough to ADB on the device.
+</p>
+
+<p>If the vendor ID or the product ID found in USB device descriptor do not
+match expected values, the accessory cannot determine if the device supports
+Android accessory mode. The accessory should attempt to start the device in
+accessory mode (detailed below) to determine device support.</p>
+
+<h2 id="attempt-to-start-in-accessory-mode">Attempt to start in accessory
+mode</h2>
+
+<p>If the vendor and product IDs do not correspond to an Android-powered device
+in accessory mode, the accessory cannot discern whether the device supports (but
+is not in) accessory mode or if the device does not support accessory mode. This
+can occur because devices that support accessory mode (but are not in that mode)
+initially report the <em>device</em> manufacturer vendor and product IDs instead
+of the <em>AOA</em> vendor and product IDs.</p>
+
+<p>The accessory should try to start the device in accessory mode to determine
+if the device supports that mode:</p>
+
<ul>
- <li>Send a 51 control request ("Get Protocol") to figure out if the device supports the Android
- accessory protocol. A non-zero number is returned if the protocol is supported, which
- represents the version of the protocol that the device supports (currently, only version 1
- exists). This request is a control request on endpoint 0 with the following characteristics:
+ <li>Send a 51 control request ("Get Protocol") to determine if the device
+ supports the Android accessory protocol. If the device supports the protocol,
+ it returns a non-zero number that represents the supported protocol version.
+ The control request is on endpoint 0 with the following characteristics:
<pre>
requestType: USB_DIR_IN | USB_TYPE_VENDOR
@@ -75,10 +101,12 @@
device to the accessory)
</pre>
</li>
- <li>If the device returns a proper protocol version, send identifying string information to the
- device. This information allows the device to figure out an appropriate application for this
- accessory and also present the user with a URL if an appropriate application does not exist.
- These requests are control requests on endpoint 0 (for each string ID) with the following
+
+ <li>If the device returns a supported protocol version, send a control request
+ with identifying string information to the device. This information allows the
+ device to determine an appropriate application for the accessory (or present a
+ URL to the user if an appropriate application does not exist). The control
+ request is on endpoint 0 (for each string ID) with the following
characteristics:
<pre>
@@ -89,8 +117,8 @@
data zero terminated UTF8 string sent from accessory to device
</pre>
- <p>The following string IDs are supported, with a maximum size of 256 bytes for each string
- (must be zero terminated with `\0`).</p>
+ <p>The following string IDs are supported, with a maximum size of 256 bytes
+ for each string (must be zero-terminated with <code>\0</code>).</p>
<pre>
manufacturer name: 0
@@ -101,8 +129,9 @@
serial number: 5
</pre>
</li>
- <li>When the identifying strings are sent, request the device start up in accessory mode. This
- request is a control request on endpoint 0 with the following characteristics:
+
+ <li>Send a control request to ask the device to start in accessory mode. The
+ control request is on endpoint 0 with the following characteristics:
<pre>
requestType: USB_DIR_OUT | USB_TYPE_VENDOR
@@ -114,25 +143,37 @@
</li>
</ul>
-<p>After sending the final control request, the connected USB device should re-introduce itself
-on the bus in accessory mode and the accessory can re-enumerate the connected devices. The
-algorithm jumps back to
-<a href="#determine-accessory-mode-support">determining the device's accessory mode support</a>
-to check for the vendor and product ID. The vendor ID and product ID of the device will be
-different if the device successfully switched to accessory mode and will now correspond to
-Google's vendor and product IDs instead of the device manufacturer's IDs. The accessory can now
-<a href="#establish-communication-with-the-device">establish communication with the device</a>.</p>
-<p>If at any point these steps fail, the device does not support Android accessory mode and the
-accessory should wait for the next device to be connected.</p>
-<h2 id="establish-communication-with-the-device">Establish Communication with the Device</h2>
-<p>If an Android-powered device in accessory mode is detected, the accessory can query the
-device's interface and endpoint descriptors to obtain the bulk endpoints to communicate with the
-device. An Android-powered device that has a product ID of <code>0x2D00</code> has one interface with two bulk
-endpoints for input and output communication. A device with product ID of <code>0x2D01</code> has two
-interfaces with two bulk endpoints each for input and output communication. The first interface
-is for standard communication while the second interface is for ADB communication. To communicate
-on an interface, all you need to do is find the first bulk input and output endpoints, set the
-device's configuration to a value of 1 with a <code>SET_CONFIGURATION</code> (<code>0x09</code>) device request, then
-communicate using the endpoints.</p>
+<p>After completing these steps, the accessory should wait for the connected USB
+device to re-introduce itself on the bus in accessory mode, then re-enumerate
+connected devices. The algorithm returns to
+<a href="#determine-accessory-mode-support">determine accessory mode support</a>
+to check the vendor and product IDs, which should be correct (e.g. correspond to
+Google's vendor and product IDs instead of the device manufacturer's IDs) if the
+device successfully switched to accessory mode. If IDs are correct, the
+accessory moves to <a href="#establish-communication-with-the-device">establish
+communication with the device</a>.</p>
+
+<p>If any step fails, the accessory determines the device does not support
+Android accessory mode and waits for the next device to connect.</p>
+<h2 id="establish-communication-with-the-device">Establish communication with
+the device</h2>
+
+<p>If the accessory detects an Android-powered device in accessory mode, the
+accessory can query the device interface and endpoint descriptors to obtain the
+bulk endpoints for communicating with the device.</p>
+
+<p>The number of interfaces and bulk endpoints depends on the product ID. An
+Android-powered device with a product ID of:</p>
+
+<ul>
+<li><code>0x2D00</code> has one interface with two bulk endpoints for input and
+output communication.</li>
+<li><code>0x2D01</code> has two interfaces with two bulk endpoints each for
+input and output communication. The first interface handles standard
+communication and the second interface handles ADB communication. To use an
+interface, locate the first bulk input and output endpoints, set the
+device configuration to a value of 1 with a <code>SET_CONFIGURATION</code>
+(<code>0x09</code>) device request, then communicate using the endpoints.</li>
+</ul>
\ No newline at end of file
diff --git a/src/accessories/aoa2.jd b/src/accessories/aoa2.jd
index c48bf25..2cbdc47 100644
--- a/src/accessories/aoa2.jd
+++ b/src/accessories/aoa2.jd
@@ -2,7 +2,7 @@
@jd:body
<!--
- Copyright 2013 The Android Open Source Project
+ Copyright 2015 The Android Open Source Project
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
@@ -16,24 +16,37 @@
See the License for the specific language governing permissions and
limitations under the License.
-->
-<p>This document describes the changes to the Android Open Accessory (AOA) protocol since its
-initial release, and is a supplement to the documentation of the
-<a href="{@docRoot}accessories/aoa.html">first release of AOA</a>.</p>
-<p>The Android Open Accessory Protocol 2.0 adds two new features: audio output (from the Android
-device to the accessory) and support for the accessory acting as one or more Human Interface Devices
-(HID) to the Android device. The Android SDK APIs available to Android application developers
-remain unchanged.</p>
-<h2 id="detecting-android-open-accessory-20-support">Detecting Android Open Accessory 2.0 Support</h2>
-<p>In order for an accessory to determine if a connected Android device supports accessories and at
-what protocol level, the accessory must send a <code>getProtocol()</code> command and check the result.
-Android devices supporting the initial version of the Android Open Accessory protocol return a
-<code>1</code>, representing the protocol version number. Devices that support the new features described
-in this document must return <code>2</code> for the protocol version. Version 2.0 of the protocol is
-upwardly compatible, so accessories designed for the original accessory protocol still work
-with newer Android devices. The following example from the Accessory Development Kit 2011
+<p>This document describes changes in the Android Open Accessory (AOA) protocol
+since its initial release and supplements
+<a href="{@docRoot}accessories/aoa.html">AOA 1.0 documentation</a>. AOAv2
+adds the following features:</p>
+
+<ul>
+<li>Audio output (from the Android device to the accessory).</li>
+<li>Support for the accessory acting as one or more Human Interface Devices
+(HID) to the Android device.</li>
+</ul>
+
+<p>Android SDK APIs available to Android application developers are unchanged.
+</p>
+
+
+<h2 id="detecting-android-open-accessory-20-support">Detecting AOAv2 support</h2>
+
+<p>To determine if a connected Android device supports accessories and the
+supported protocol version, an accessory must send a <code>getProtocol()</code>
+command and check the result. Android devices that support only the feautures
+in AOAv1 must return <code>1</code> as the protocol version; devices that
+support the additional feautres in AOAv2 must return <code>2</code> as the
+protocol version. AOAv2 is backward-compatible with AOAv1, so accessories
+designed for the original accessory protocol continue to work with newer Android
+devices.</p>
+
+<p>The following example from the Accessory Development Kit 2011
<a href="http://developer.android.com/tools/adk/adk2.html#src-download">source code</a>
-(<code><adk-src>/adk1/board/AndroidAccessory/AndroidAccessory.cpp</code>) library demonstrates this protocol
-check:</p>
+(<code><adk-src>/adk1/board/AndroidAccessory/AndroidAccessory.cpp</code>)
+library demonstrates this protocol check:</p>
+
<pre><code>bool AndroidAccessory::switchDevice(byte addr)
{
int protocol = getProtocol(addr);
@@ -56,35 +69,77 @@
return true;
}
</code></pre>
-<p>AOA 2.0 includes new USB product IDs, one for each combination of USB interfaces available when
-in accessory mode. The possible USB interfaces are:</p>
-<ul>
-<li><strong>accessory</strong> - An interface providing 2 bulk endpoints for communicating with an
-Android application.</li>
-<li><strong>audio</strong> - A new standard USB audio class interface for streaming audio
-from an Android device to an accessory.</li>
-<li><strong>adb</strong> - An interface intended only for debugging purposes while developing an
-accessory. Only enabled if the user has USB Debugging enabled in Settings on the Android device.</li>
-</ul>
-<p>In AOA 1.0, there are only two USB product IDs:</p>
-<ul>
-<li><code>0x2D00</code> - accessory</li>
-<li><code>0x2D01</code> - accessory + adb</li>
-</ul>
-<p>AOA 2.0 adds an optional USB audio interface and, therefore, includes product IDs for the new
-combinations of USB interfaces:</p>
-<ul>
-<li><code>0x2D02</code> - audio</li>
-<li><code>0x2D03</code> - audio + adb</li>
-<li><code>0x2D04</code> - accessory + audio</li>
-<li><code>0x2D05</code> - accessory + audio + adb</li>
-</ul>
-<h2 id="audio-support">Audio Support</h2>
-<p>AOA 2.0 includes optional support for audio output from an Android device to an accessory. This
-version of the protocol supports a standard USB audio class interface that is capable of 2 channel
-16-bit PCM audio with a bit rate of 44100 Khz. AOA 2.0 is currently limited to this output mode, but
-additional audio modes may be added in the future.</p>
-<p>To enable the audio support, the accessory must send a new USB control request:</p>
+
+<p>AOAv2 includes new USB product IDs for each combination of USB interfaces
+available in accessory mode:</p>
+
+<table id="AOA-version-comparison">
+<tbody>
+
+<tr>
+<th>Version</th>
+<th>Product ID</th>
+<th>Communication</th>
+<th>Description</th>
+</tr>
+
+<tr>
+<td rowspan="2">AOAv1</td>
+<td><code>0x2D00</code></td>
+<td>accessory</td>
+<td>Provides two bulk endpoints for communicating with an Android
+application.</td>
+</tr>
+
+<tr>
+<td><code>0x2D01</code></td>
+<td>accessory + adb</td>
+<td>For debugging purposes during accessory development. Available only if the
+user has enabled <em>USB Debugging</em> in the Android device settings.</td>
+</tr>
+
+<tr>
+<td rowspan="4">AOAv2</td>
+<td><code>0x2D02</code></td>
+<td>audio</td>
+<td>For streaming audio from an Android device to an accessory.</td>
+</tr>
+
+<tr>
+<td><code>0x2D03</code></td>
+<td>audio + adb</td>
+<td></td>
+</tr>
+
+<tr>
+<td><code>0x2D04</code></td>
+<td>accessory + audio</td>
+<td></td>
+</tr>
+
+<tr>
+<td><code>0x2D05</code></td>
+<td>accessory + audio + adb</td>
+<td></td>
+</tr>
+
+</tbody>
+</table>
+
+
+<p>Product IDs used in AOAv1 (<code>0x2D00</code> and <code>0x2D01</code>)
+continue to be supported in AOAv2.</p>
+
+<h2 id="audio-support">Audio support</h2>
+
+<p>AOAv2 includes support for audio output from an Android device to an
+accessory via a standard USB audio class interface capable of 2 channel, 16-bit
+PCM audio with a bit rate of 44100 Khz (additional audio modes may be added in
+the future).</p>
+
+<p>To enable audio support, the accessory must send a new USB control request:
+</p>
+
<pre><code>**SET_AUDIO_MODE**
requestType: USB_DIR_OUT | USB_TYPE_VENDOR
request: 58
@@ -93,39 +148,53 @@
index: 0
data none
</code></pre>
-<p>This command must be sent <em>before</em> sending the <code>ACCESSORY_START</code> command for
-entering accessory mode.</p>
-<h2 id="hid-support">HID Support</h2>
-<p>AOA 2.0 allows the accessory to register one or more USB Human Interface Devices (HID) with
-an Android device. This approach reverses the direction of communication for typical USB HID
-devices like USB mice and keyboards. Normally, the HID device is a peripheral connected to a USB
-host like a personal computer. But in the case of the AOA protocol, the USB host acts as one or more
-input devices to a USB peripheral.</p>
-<p>HID support in AOA 2.0 is simply a proxy for standard HID events. The implementation makes no
-assumptions about the content or type of events and merely passes it through to the input system,
-so an AOA 2.0 accessory can act as any HID device (mouse, keyboard, game controller, etc.). It
-can be used for something as simple as the play/pause button on a media dock, or something as
-complicated as a docking station with a mouse and full QWERTY keyboard.</p>
-<p>The AOA 2.0 protocol adds four new USB control requests to allow the accessory to act as one or
-more HID input devices to the Android device. Since HID support is done entirely through
-control requests on endpoint zero, no new USB interface is needed to provide this support. The
-control requests are as follows:</p>
+
+<p>This command must be sent <em>before</em> sending the
+<code>ACCESSORY_START</code> command for entering accessory mode.</p>
+
+<h2 id="hid-support">HID support</h2>
+
+<p>AOAv2 allows accessories to register one or more USB Human Interface
+Devices (HID) with an Android device. This approach reverses the direction of
+communication for typical USB HID devices such as USB mice and keyboards.
+Normally, the HID device is a peripheral connected to a USB host (i.e. a
+personal computer), but in AOA the USB host can act as one or more input
+devices to a USB peripheral.</p>
+
+<p>HID support is a proxy for standard HID events; the
+implementation makes no assumptions about the content or type of events and
+simply passes it through to the input system, enabling an AOAv2 accessory to
+act as any HID device (mouse, keyboard, game controller, etc.). You can use HID
+support to provide basic functionality, such as a play/pause button on a media
+dock, or for advanced functionality such as a docking station with a mouse and
+full QWERTY keyboard.</p>
+
+<p>AOAv2 adds new USB control requests that allow the accessory to act as
+one or more HID input devices to the Android device. HID support is handled
+entirely through control requests on endpoint zero, so no new USB interface is
+needed. The four new control requests are:</p>
+
<ul>
-<li><strong>ACCESSORY_REGISTER_HID</strong> registers a new HID device with the Android device.
-The accessory provides an ID number that is used to identify the HID device for the other three
-calls. This ID is valid until USB is disconnected or until the accessory sends
-<code>ACCESSORY_UNREGISTER_HID</code> to unregister the HID device.</li>
-<li><strong>ACCESSORY_UNREGISTER_HID</strong> unregisters a HID device that was previously
-registered with <code>ACCESSORY_REGISTER_HID</code>.</li>
-<li><strong>ACCESSORY_SET_HID_REPORT_DESC</strong> sends a report descriptor for a HID device to
-the Android device. This request is used to describe the capabilities of the HID device, and must
-be sent before reporting any HID events to the Android device. If the report descriptor is larger
-than the maximum packet size for endpoint zero, multiple <code>ACCESSORY_SET_HID_REPORT_DESC</code> commands
-are sent in order to transfer the entire descriptor.</li>
-<li><strong>ACCESSORY_SEND_HID_EVENT</strong> sends input events from the accessory to the Android
+<li><strong>ACCESSORY_REGISTER_HID</strong> registers a new HID device with the
+Android device. The accessory provides an ID used to identify the HID device for
+the other three calls. This ID is valid until USB disconnects or until the
+accessory sends <code>ACCESSORY_UNREGISTER_HID</code> to unregister the HID
device.</li>
+<li><strong>ACCESSORY_UNREGISTER_HID</strong> unregisters a HID device
+previously registered with <code>ACCESSORY_REGISTER_HID</code>.</li>
+<li><strong>ACCESSORY_SET_HID_REPORT_DESC</strong> sends a report descriptor for
+a HID device to the Android device. This request is used to describe the
+capabilities of the HID device and must be sent before reporting any HID events
+to the Android device. If the report descriptor is larger than the maximum
+packet size for endpoint zero, multiple
+<code>ACCESSORY_SET_HID_REPORT_DESC</code> commands are sent to transfer the
+entire descriptor.</li>
+<li><strong>ACCESSORY_SEND_HID_EVENT</strong> sends input events from the
+accessory to the Android device.</li>
</ul>
-<p>The code definitions for these new control requests are as follows:</p>
+
+<p>The code definitions for the new control requests are:</p>
+
<pre><code>/* Control request for registering a HID device.
* Upon registering, a unique ID is sent by the accessory in the
* value parameter. This ID will be used for future commands for
@@ -174,23 +243,34 @@
*/
#define ACCESSORY_SEND_HID_EVENT 57
</code></pre>
-<h2 id="interoperability-with-aoa-10-features">Interoperability with AOA 1.0 Features</h2>
-<p>The original <a href="{@docRoot}accessories/aoa.html">AOA protocol</a> provided support for an Android
-application to communicate directly with a USB host (accessory) over USB. AOA 2.0 keeps that
-support, but adds new features to allow the accessory to communicate with the Android operating
-system itself (specifically the audio and input systems). The design of the AOA 2.0 makes it is
-possible to build an accessory that also makes use of the new audio and/or HID support in addition
-to the original feature set. Simply use the new features described in this document in addition to
-the original AOA protocol features.</p>
-<h2 id="connecting-aoa-20-without-an-android-app">Connecting AOA 2.0 without an Android App</h2>
-<p>It is possible to design an accessory (for example, an audio dock) that uses the new audio and
-HID support, but does not need to communicate with an application on the Android device. In that
-case, the user would not want to see the dialog prompts related to finding and associating the newly
-attached accessory with an Android application that can communicate with it. To prevent these
-dialogs from appearing after the device and accessory are connected, the accessory can simply not
-send the manufacturer and model names to the Android device. If these strings are not provided to
-the Android device, then the accessory is able to make use of the new audio and HID support in AOA
-2.0 without the system attempting to find an application to communicate with the accessory. Also,
-if these strings are not provided, the accessory USB interface is not present in the Android
-device USB configuration after the device enters accessory mode.</p>
+<h2 id="interoperability-with-aoa-10-features">Interoperability with AOAv1</h2>
+
+<p>The original protocol (<a href="{@docRoot}accessories/aoa.html">AOAv1</a>)
+provides support for an Android application to communicate directly with a USB
+host (accessory) over USB. AOAv2 continues this support and adds new features
+to allow the accessory to communicate with the Android operating system itself
+(specifically the audio and input systems). The design of AOAv2 makes it
+possible to build an accessory that uses the new audio and HID support
+in addition to the original feature set. Simply use the new features along with
+the original features.</p>
+
+<h2 id="connecting-aoa-20-without-an-android-app">Connecting AOAv2 without an
+Android app</h2>
+
+<p>You can design an accessory (such as an audio dock) that uses audio and HID
+support but does not communicate with an application on the Android device. For
+these accessories, users do not need to receive dialog prompts for finding and
+associating the newly attached accessory with an Android application that can
+communicate with it.</p>
+
+<p>To suppress such dialogs after an accessory connects, the
+accessory can choose not to send the manufacturer and model names to the Android
+device. When these strings are not provided to the Android device:</p>
+
+<ul>
+<li>The system does not attempt to find an application to communicate with the
+accessory.</li>
+<li>The accessory USB interface is not present in the Android device USB
+configuration after the device enters accessory mode.</li>
+</ul>
\ No newline at end of file
diff --git a/src/accessories/audio.jd b/src/accessories/audio.jd
index 92ce6fe..72c5e1d 100644
--- a/src/accessories/audio.jd
+++ b/src/accessories/audio.jd
@@ -2,7 +2,7 @@
@jd:body
<!--
- Copyright 2014 The Android Open Source Project
+ Copyright 2015 The Android Open Source Project
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
@@ -24,53 +24,67 @@
</div>
</div>
-<p>In implementing an audio accessory, such as a headset, headphone amplifier,
-microphone, DAC/ADC, or dock, you should consider how your accessory will
-connect with Android devices. In particular, you should decide
-if your accessory will use wired a 3.5 mm headset connector, Universal Serial
-Bus (USB), or a Bluetooth connection to stream music or other audio content.</p>
+<p>When implementing an audio accessory such as a headset, headphone amplifier,
+microphone, DAC/ADC, or dock, consider how the accessory connects to Android
+devices. The following sections describe wired 3.5 mm headset connections,
+Universal Serial Bus (USB) connections, and Bluetooth connections for streaming
+music or other audio content.</p>
+
<h2 id="audio-over-35mm">Audio over 3.5 mm headset connector</h2>
-<p>Many Android-based devices include a 3.5 mm (“mini”) headset connector. In
-addition to the traditional stereo output and mono input features, the <a
-href="headset-spec.html">Wired audio headset specification</a> defines standard
-impedances and functions so a range of Android devices and headsets can inter-operate.</p>
+<p>Many Android devices include a 3.5 mm (“mini”) headset connector.
+In addition to traditional stereo output and mono input features, the
+<a href="headset/specification.html">Wired audio headset specification</a>
+defines standard impedances and functions that enable interoperability between
+a range of Android devices and headsets.</p>
<h2 id="audio-over-usb">Audio over USB</h2>
<p>Android can use USB in several modes:</p>
<ul>
- <li>development
- <li>accessory
- <li>host
+ <li><strong>Development</strong>. Does not support audio. </li>
+ <li><strong>Accessory</strong>. Provided by Android Open Accessory (AOA) 2.0
+ and provides limited audio capability, as described in
+ <a href="custom.html#audio-over-usb">Connecting custom audio over USB</a>.
+ </li>
+ <li><strong>Host</strong>. Enables the Android device to drive the USB bus
+ and operate with a wide range of USB-based peripherals, including audio
+ interfaces. Host mode audio is described in
+ <a href="{@docRoot}devices/audio/usb.html">USB Digital Audio</a>.</li>
</ul>
-<p>In the development mode, there is no audio capability.</p>
-<p>Accessory mode is provided by the Open Accessory (AOA) protocol version 2.0.
-There is limited audio capability in accessory mode, as described in <a
-href="custom.html#audio-over-usb">Connecting custom audio over USB</a>.</p>
-<p>Host mode enables the Android device to drive the USB bus and operate with a
-wide range of USB-based peripherals, including audio interfaces. Host mode
-audio is described in <a href="{@docRoot}devices/audio/usb.html">USB Digital Audio</a>
<h2 id="audio-over-bluetooth">Audio over Bluetooth</h2>
-<p>An accessory that connects with Android over Bluetooth can use an Advanced Audio Distribution
-Profile (A2DP) connection stream music for playback. Playing audio over a Bluetooth with A2DP is
-supported on Android 1.5 (API Level 3) and higher. An Android user can connect to an accessory
-that supports this profile using the system Settings > Bluetooth and play music directly to the
-accessory without the need for a secondary application.</p>
-<p><strong>Note:</strong> If you want to provide a custom application for output to your audio
-accessory, note that the Android 3.0 (API Level 11) allows applications to operate an A2DP
-connection using the
-<a href="http://developer.android.com/reference/android/bluetooth/BluetoothA2dp.html"><code>BluetoothA2dp</code></a>
-class.</p>
+<p>An accessory that connects with Android over Bluetooth can use an Advanced
+Audio Distribution Profile (A2DP) connection stream music for playback. Playing
+audio over a Bluetooth with A2DP is supported on Android 1.5 (API Level 3) and
+higher. An Android user can connect to an accessory that supports this profile
+using the system Settings > Bluetooth and play music directly to the
+accessory without a secondary application.</p>
+
+<p>As of Android 3.0 (API Level 11), applications can operate an A2DP connection
+using the
+<a href="http://developer.android.com/reference/android/bluetooth/BluetoothA2dp.html">
+<code>BluetoothA2dp</code></a> class. To provide a custom application for
+output to an audio accessory, you must use Android 3.0 or higher.
+</p>
+
<h3 id="next-steps_1">Next steps</h3>
-<p>To get started on building an audio accessory that uses a Bluetooth connection:</p>
+<p>To get started building an audio accessory that uses a Bluetooth connection:
+</p>
<ul>
-<li>Select a hardware platform or build an hardware device that can support Bluetooth
- communications and the A2DP connection profile.</li>
+<li>Select a hardware platform or build an hardware device that can support
+Bluetooth communications and the A2DP connection profile.</li>
<li>Review the ADK 2012
- <a href="http://developer.android.com/tools/adk/adk2.html#src-download">firmware source code</a>
- (<code><adk-src>/adk2012/board/library/ADK2/</code>), which includes an example implementation
- of an audio playback accessory using a Bluetooth connection.</li>
+ <a href="http://developer.android.com/tools/adk/adk2.html#src-download">firmware
+ source code</a> (<code><adk-src>/adk2012/board/library/ADK2/</code>),
+ which includes an example implementation of an audio playback accessory using
+ a Bluetooth connection.</li>
</ul>
-<p><strong>Note:</strong> The ADK 2012 source code includes an open source Bluetooth stack that
-is built for the Texas Instruments CC2564 chip, but can work with any Bluetooth chip that
-implements a standard Host/Controller Interface (HCI).</p>
+
+<p class="note"><strong>Note:</strong> The ADK 2012 source code includes an open
+source Bluetooth stack built for the Texas Instruments CC2564 chip, but is
+designed to work with any Bluetooth chip that implements a standard
+Host/Controller Interface (HCI).</p>
+
+<h2 id="midi-over-usb">MIDI over USB and Bluetooth LE</h2>
+<p>Both USB and Bluetooth Low Energy can be used as transports for the
+<a href="http://en.wikipedia.org/wiki/MIDI">MIDI</a> protocol. For details, see
+<a href="{@docRoot}devices/audio/midi.html">MIDI</a>.</p>
\ No newline at end of file
diff --git a/src/accessories/custom.jd b/src/accessories/custom.jd
index 560f182..c4ff0f6 100644
--- a/src/accessories/custom.jd
+++ b/src/accessories/custom.jd
@@ -2,7 +2,7 @@
@jd:body
<!--
- Copyright 2014 The Android Open Source Project
+ Copyright 2015 The Android Open Source Project
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
@@ -24,88 +24,109 @@
</div>
</div>
-<p>An accessory for Android can be anything: keyboard, thermometer, robot, lighting control or
-anything else you can imagine. Accessories for Android all have one thing in common; they all
-connect to an Android device in some way. When starting out to build an accessory, you should
-decide how your accessory will connect to Android devices. This page gives you quick overview of
-your options for connecting your Android accessory and resources to help you get started.</p>
+<p>An accessory for Android can be anything: keyboard, thermometer, robot,
+lighting control, or anything else you can imagine. All Android accessories
+connect to an Android device in some way, so when building an accessory you must
+consider the type of connections your accessory will use. This page provides a
+quick overview of your options for connecting your Android accessory and
+a list of resources to help you get started.</p>
+
<h2 id="connecting-over-usb">Connecting over USB</h2>
-<p>An accessory that connects to an Android device through a USB cable must support the Android
-Open Accessory (AOA) protocol, which specifies how an accessory can establish communication with
-an Android device over a USB cable. Due to the low power output of Android devices, the AOA
-protocol requires the accessory act as a USB host, which means that the connecting accessory must
-power the bus.</p>
-<p>The AOA protocol has two versions which support different types of communication. Version
-1.0 supports a generic accessory communication and adb debugging. This version of the protocol is
-supported by the platform in Android 3.1 (API Level 12) and higher, and supported through an
-<a href="https://developers.google.com/android/add-ons/google-apis/">Add-On Library</a> in Android
-2.3.4 (API Level 10) and higher. Version 2.0 of the protocol is available in Android 4.1 (API Level
-16) and adds audio streaming and human interface device (HID) capabilities.</p>
-<p>If you use the general accessory protocol to communicate with your accessory (rather than the
-adb or audio protocol), you must provide an Android application that can detect the connection of
-your USB accessory and establish communication.</p>
-<h3 id="next-steps">Next steps</h3>
-<p>To get started on building an Android accessory that uses a USB connection:</p>
+<p>An accessory that connects to an Android device through a USB cable must
+support the Android Open Accessory (AOA) protocol, which specifies how an
+accessory can establish communication with an Android device via USB.
+Due to the low power output of Android devices, AOA requires the accessory to
+act as a USB host, meaning the connecting accessory must power the bus.</p>
+
+<p>AOA has two versions that support different types of communication:</p>
<ul>
-<li>Select a hardware platform or build a hardware device that can support USB host mode.</li>
-<li>Review the <a href="{@docRoot}accessories/index.html">AOA protocol</a> specifications to understand
- how to implement this protocol on your accessory hardware. Implementing the
- <a href="{@docRoot}accessories/aoa2.html">AOA 2.0 protocol</a> is recommended for all new Android USB
- accessories.</li>
-<li>Review the ADK 2012 <a href="http://developer.android.com/tools/adk/adk2.html#src-download">firmware source code</a>
- (<code><adk-src>/adk2012/board/library/ADK2/</code>), which demonstrates an implementation of an accessory
- using a USB connection for general data communications and audio streaming.</li>
-<li>If you are planning to build an Android application that communicates with your accessory
- via USB, review the ADK 2012 Android
- <a href="http://developer.android.com/tools/adk/adk2.html#src-download">application source code</a>
- (<code><adk-src>/adk2012/app/</code>).</li>
+<li><strong>AOAv1</strong>. Supports generic accessory communication and adb
+debugging. Available in Android 3.1 (API Level 12) and higher and supported
+through an
+<a href="https://developers.google.com/android/add-ons/google-apis/">Add-On
+Library</a> in Android 2.3.4 (API Level 10) and higher.</li>
+<li><strong>AOAv2</strong>. Supports audio streaming and human interface
+device (HID) capabilities. Available in Android 4.1 (API Level 16).</li>
</ul>
+
+<p>If you use the general accessory protocol to communicate with your accessory
+(rather than the adb or audio protocol), you must provide an Android application
+that can detect the connection of your USB accessory and establish communication.
+</p>
+
+<h3 id="next-steps_0">Next steps</h3>
+<p>To get started building an Android accessory that uses a USB connection:
+</p>
+<ul>
+<li>Select a hardware platform or build a hardware device that can support USB
+host mode.</li>
+<li>Review <a href="{@docRoot}accessories/protocol.html">AOA</a> specifications to
+understand how to implement this protocol on your accessory hardware.
+Implementing <a href="{@docRoot}accessories/aoa2.html">AOAv2</a> is
+recommended for all new Android USB accessories.</li>
+<li>Review the ADK 2012
+<a href="http://developer.android.com/tools/adk/adk2.html#src-download">firmware
+source code</a> (<code><adk-src>/adk2012/board/library/ADK2/</code>),
+which demonstrates an implementation of an accessory using a USB connection for
+general data communications and audio streaming.</li>
+<li>When planning to build an Android application that communicates with your
+accessory via USB, review the ADK 2012 Android
+<a href="http://developer.android.com/tools/adk/adk2.html#src-download">application
+source code</a> (<code><adk-src>/adk2012/app/</code>).</li>
+</ul>
+
<h2 id="connecting-over-bluetooth">Connecting over Bluetooth</h2>
-<p>An accessory that connects with Android devices over a Bluetooth connection can use the
-various connection profiles supported by Android, including the Simple Serial Protocol (SSP) and
-Advanced Audio Distribution Profile (A2DP) profile. An accessory that uses Bluetooth to connect to
-Android devices must support Bluetooth communications and at least one of the supported connection
-profiles.</p>
-<p>Users must enable Bluetooth on their Android device and pair with your accessory in order to
-use it. You can also provide a secondary Android application that handles any specialized
-communication, such as data input or control outputs, to interface with your accessory.</p>
+<p>An accessory that connects with Android devices over a Bluetooth connection
+can use connection profiles supported by Android, including the Simple Serial
+Protocol (SSP) and Advanced Audio Distribution Profile (A2DP) profile. An
+accessory that uses Bluetooth to connect to Android devices must support
+Bluetooth communications and at least one of the supported connection profiles.
+</p>
+<p>Users must enable Bluetooth on their Android device and pair with your
+accessory to use the accessory. You can also provide a secondary Android
+application that handles specialized communication such as data input or control
+outputs to interface with your accessory.</p>
+
<h3 id="next-steps_1">Next steps</h3>
-<p>To get started on building an Android accessory that uses a Bluetooth connection:</p>
+<p>To get started building an Android accessory that uses a Bluetooth connection:
+</p>
<ul>
-<li>Select a hardware platform or build an hardware device that can support Bluetooth
- communications and an Android supported connection profile, such as SSP or A2DP.</li>
-<li>Review the ADK 2012 <a href="http://developer.android.com/tools/adk/adk2.html#src-download">firmware source code</a>
- (<code><adk-src>/adk2012/board/library/ADK2/</code>), which includes an example implementation
- of general data communications and audio streaming using a Bluetooth connection.</li>
-<li>If you are planning to build an Android application that communicates with your accessory
- via Bluetooth, review the ADK 2012 Android
- <a href="http://developer.android.com/tools/adk/adk2.html#src-download">application source code</a>
- (<code><adk-src>/adk2012/app/</code>).</li>
+<li>Select a hardware platform or build an hardware device that can support
+Bluetooth communications and an Android supported connection profile, such as
+SSP or A2DP.</li>
+<li>Review the ADK 2012
+<a href="http://developer.android.com/tools/adk/adk2.html#src-download">firmware
+source code</a> (<code><adk-src>/adk2012/board/library/ADK2/</code>),
+which includes an example implementation of general data communications and
+audio streaming using a Bluetooth connection.</li>
+<li>When planning to build an Android application that communicates with your
+accessory via Bluetooth, review the ADK 2012 Android
+<a href="http://developer.android.com/tools/adk/adk2.html#src-download">application
+source code</a> (<code><adk-src>/adk2012/app/</code>).</li>
</ul>
-<p><strong>Note:</strong> The ADK 2012 source code includes an open source Bluetooth stack which
-is built for the Texas Instruments CC2564 chip, but can work with any Bluetooth chip that
-supports a standard Host/Controller Interface (HCI).</p>
+
+<p class="note"><strong>Note:</strong> The ADK 2012 source code includes an open
+source Bluetooth stack built for the Texas Instruments CC2564 chip but is
+designed to work with any Bluetooth chip that supports a standard
+Host/Controller Interface (HCI).</p>
<h2 id="audio-over-usb">Connecting audio over USB</h2>
-<p>An accessory that connects with Android over USB connection may use the Android Open
-Accessory (AOA) protocol version 2.0. This version of the AOA protocol is supported on Android 4.1
-(API Level 16) and higher. Once an Android device connects to an accessory that supports this
-protocol, the Android system treats it as a standard audio output device and routes all audio to
-that accessory. No secondary software application is required on the Android device.</p>
-<p><strong>Note:</strong> Due to the low power output of Android devices, the Android Open Accessory
-Protocol requires that accessories act as a USB host, which means that the connecting accessory
-must power the bus.</p>
-<h3 id="next-steps">Next steps</h3>
-<p>To get started on building an audio accessory that uses a USB connection:</p>
-<ul>
-<li>Select a hardware platform or build a hardware device that can support USB host mode.</li>
-<li>Review the <a href="{@docRoot}accessories/aoa2.html">AOA 2.0 protocol</a> specification to understand
- how to implement this protocol on your accessory hardware.</li>
-<li>Review the ADK 2012 <a href="http://developer.android.com/tools/adk/adk2.html#src-download">firmware source code</a>
- (<code><adk-src>/adk2012/board/library/ADK2/</code>), which includes an example implementation
- of an audio playback accessory using a USB connection.</li>
-</ul>
-<p><strong>Note:</strong> The AOA 2.0 protocol also supports the
-<a href="{@docRoot}accessories/aoa2.html#hid-support">human interface device</a> (HID) protocol through a USB
-connection, enabling accessories such as audio docks to provide hardware play back controls such
-as pause, fast-forward or volume buttons.</p>
+<p>An accessory that connects with Android over USB can use AOAv2 (supported on
+Android 4.1 (API Level 16) and higher. After an Android device connects to an
+accessory that supports this protocol, the Android system treats it as a
+standard audio output device and routes all audio to that accessory. No
+secondary software application is required on the Android device.</p>
+
+<p class="note"><strong>Note:</strong> Due to the low power output of Android
+devices, AOA requires accessories to act as a USB host, meaning the connecting
+accessory must power the bus.</p>
+
+<h3 id="next-steps_2">Next steps</h3>
+<p>To get started building an audio accessory that uses a USB connection, see
+<a href="#next-steps_0">next steps for USB connections.</a></p>
+
+<p>AOAv2 also supports the
+<a href="{@docRoot}accessories/aoa2.html#hid-support">human interface device</a>
+(HID) protocol through a USB connection, enabling accessories such as audio
+docks to provide hardware play back controls such as pause, fast-forward or
+volume buttons.</p>
\ No newline at end of file
diff --git a/src/accessories/headset-spec.jd b/src/accessories/headset-spec.jd
deleted file mode 100644
index c9a749e..0000000
--- a/src/accessories/headset-spec.jd
+++ /dev/null
@@ -1,697 +0,0 @@
-page.title=Wired audio headset specification
-@jd:body
-
-<!--
- Copyright 2014 The Android Open Source Project
-
- Licensed under the Apache License, Version 2.0 (the "License");
- you may not use this file except in compliance with the License.
- You may obtain a copy of the License at
-
- http://www.apache.org/licenses/LICENSE-2.0
-
- Unless required by applicable law or agreed to in writing, software
- distributed under the License is distributed on an "AS IS" BASIS,
- WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- See the License for the specific language governing permissions and
- limitations under the License.
--->
-<div id="qv-wrapper">
- <div id="qv">
- <h2>In this document</h2>
- <ol id="auto-toc">
- </ol>
- </div>
-</div>
-
-<p><em>Version 1.1</em></p>
-
-<p>This document specifies the requirements for headsets and mobile devices to
-function uniformly across the Android ecosystem. It is separated into two
-sections beginning with the specifications for the headset
-accessory followed by the specifications for the mobile device.</p>
-
-<h2 id=headset_accessory_plug_specifications>Headset Accessory (Plug) Specifications</h2>
-
-<p>The requirements in the following section apply to the headset accessory.</p>
-
-<h3 id=functions>Functions</h3>
-
-<table>
- <tr>
- <th>
-<p><strong>Function</strong></p>
-</th>
- <th>
-<p><strong>Accessory Support</strong></p>
-</th>
- </tr>
- <tr>
- <td>
-<p>Stereo Audio Out</p>
-</td>
- <td>
-<p><strong>Required</strong></p>
-</td>
- </tr>
- <tr>
- <td>
-<p>Audio in (Mic)</p>
-</td>
- <td>
-<p><strong>Required</strong></p>
-</td>
- </tr>
- <tr>
- <td>
-<p>Ground</p>
-</td>
- <td>
-<p><strong>Required</strong></p>
-</td>
- </tr>
-</table>
-
-<h3 id=control-function_mapping>Control-Function Mapping</h3>
-
-<table>
- <tr>
- <th>
-<p><strong>Control Function</strong></p>
-</th>
- <th>
-<p><strong>Accessory Support</strong></p>
-</th>
- <th>
-<p><strong>Description</strong></p>
-</th>
- </tr>
- <tr>
- <td>
-<p>Function A</p>
-</td>
- <td>
-<p><strong>Required</strong></p>
-</td>
- <td>
-<p>Play/pause/hook (Short Press), Trigger Assist (Long Press), Next (double press)</p>
-</td>
- </tr>
- <tr>
- <td>
-<p>Function B</p>
-</td>
- <td>
-<p>Optional</p>
-</td>
- <td>
-<p>Vol+</p>
-</td>
- </tr>
- <tr>
- <td>
-<p>Function C</p>
-</td>
- <td>
-<p>Optional</p>
-</td>
- <td>
-<p>Vol-</p>
-</td>
- </tr>
- <tr>
- <td>
-<p>Function D</p>
-</td>
- <td>
-<p>Optional</p>
-</td>
- <td>
-<p>Reserved (Nexus devices will use this reserved function to launch Google
-voice search)</p>
-</td>
- </tr>
-</table>
-
-<p><strong>Assign functions to buttons as follows</strong>:</p>
-
-<ul>
- <li> All one-button headsets must implement Function A.
- <li> Headsets with multiple buttons must implement functions according to the
-following pattern:
- <ul>
- <li> 2 functions: A and D
- <li> 3 functions: A, B, C
- <li> 4 functions: A, B, C, D
- </ul>
-</ul>
-
-<h3 id=mechanical>Mechanical</h3>
-
-<table>
- <tr>
- <th>
-<p><strong>Function</strong></p>
-</th>
- <th>
-<p><strong>Accessory Support</strong></p>
-</th>
- <th>
-<p><strong>Notes</strong></p>
-</th>
- </tr>
- <tr>
- <td>
-<p>4 conductor 3.5mm plug</p>
-</td>
- <td>
-<p><strong>Required</strong></p>
-</td>
- <td>
-<p>Ref: EIAJ-RC5325A standard</p>
-</td>
- </tr>
- <tr>
- <td>
-<p>CTIA pinout order (LRGM)</p>
-</td>
- <td>
-<p><strong>Required</strong></p>
-</td>
- <td>
-<p>Except in regions with legal requirements for OMTP pinout</p>
-</td>
- </tr>
- <tr>
- <td>
-<p>OMTP pinout order (LRMG)</p>
-</td>
- <td>
-<p>Optional</p>
-</td>
- <td></td>
- </tr>
- <tr>
- <td>
-<p>Microphone</p>
-</td>
- <td>
-<p><strong>Required</strong></p>
-</td>
- <td>
-<p>Must not be obstructed when operating headset controls</p>
-</td>
- </tr>
-</table>
-
-<h3 id=electrical>Electrical</h3>
-
-<table>
- <tr>
- <th>
-<p><strong>Function</strong></p>
-</th>
- <th>
-<p><strong>Accessory Support</strong></p>
-</th>
- <th>
-<p><strong>Description</strong></p>
-</th>
- </tr>
- <tr>
- <td>
-<p>Ear speaker impedance</p>
-</td>
- <td>
-<p><strong>16 ohms or higher</strong></p>
-</td>
- <td>
-<p>Recommend 32 - 300 ohms</p>
-</td>
- </tr>
- <tr>
- <td>
-<p>Mic DC resistance</p>
-</td>
- <td>
-<p><strong>1000 ohms or higher</strong></p>
-</td>
- <td>
-<p>Mic characteristics must be compliant with section 5.4 “Audio Recording” of
-current Android Compatibility Definition Document (CDD)</p>
-</td>
- </tr>
- <tr>
- <td>
-<p>Control Function Equivalent impedance*</p>
-
-<p>*Total impedance from positive mic terminal to GND when button is pressed with
-2.2 V mic bias applied through 2.2 kOhm resistor</p>
-</td>
- <td>
-<p><strong>0 ohm</strong></p>
-</td>
- <td>
-<p>[Function A] Play/Pause/Hook</p>
-</td>
- </tr>
- <tr>
- <td></td>
- <td>
-<p><strong>240 ohm</strong> +/- 1% resistance</p>
-</td>
- <td>
-<p>[Function B]</p>
-</td>
- </tr>
- <tr>
- <td></td>
- <td>
-<p><strong>470 ohm</strong> +/- 1% resistance</p>
-</td>
- <td>
-<p>[Function C] </p>
-</td>
- </tr>
- <tr>
- <td></td>
- <td>
-<p><strong>135 ohm</strong> +/- 1% resistance</p>
-</td>
- <td>
-<p>[Function D]</p>
-</td>
- </tr>
-</table>
-
-<p>In the following diagrams, Button A is mapped to Function A, Button B to
-Function B, and so on.</p>
-
-<h3 id=reference_headset_test_circuit_1>Reference Headset Test Circuit 1</h3>
-
-<img src="images/headset-circuit1.png" alt="Reference Headset Test Circuit 1" />
-<p class="img-caption"><strong>Figure 1.</strong> Reference headset test circuit 1</p>
-
-<p class="note"><strong>Note:</strong> The above diagram shows the CTIA pinout
-for a 4-segment plug. For the OMTP pinout, switch the positions of the MIC and
-GND segments.</p>
-
-<h3 id=reference_headset_test_circuit_2>Reference Headset Test Circuit 2</h3>
-
-<p>The second reference circuit shows how the actual resistor values (R1 - R4)
-are altered to meet this specification.</p>
-
-<img src="images/headset-circuit2.png" alt="Reference Headset Test Circuit 2" />
-<p class="img-caption"><strong>Figure 2.</strong> Reference headset test circuit 2</p>
-
-<p>The actual resistance of the buttons parallel with the microphone (R1-R4) is
-based on the microphone capsule resistance (Rmic) and the equivalent impedance
-values (ReqA-ReqD). Use the following formula:</p>
-
-<p><em>Rn=(Rmic*ReqN) / (ReqN-Rmic)</em></p>
-
-<p>Where R<em>n</em> is the actual resistance of a button, Req<em>N</em> is the
-equivalent impedance value of that button (provided), and Rmic is the
-microphone impedance value.</p>
-
-<p>The example above assumes a 5 kohm microphone impedance (Rmic). Therefore, to
-achieve an equivalent R4 impedance of 135 ohm (ReqD), the actual resistor value
-(R4) needs to be 139 ohms.</p>
-
-
-<h2 id=mobile_device_jack_specifications>Mobile Device (Jack) Specifications</h2>
-
-<p class="caution"><strong>Caution:</strong> To achieve compatibility with the
-headset specification above, devices that include a 4 conductor 3.5mm audio
-jack must meet the following specifications. Please see the <em>Analog audio
-ports</em> section of the <a
-href="{@docRoot}compatibility/android-cdd.pdf">Android Compatibility Definition
-Document (CDD)</a> for Android compatibility requirements.</p>
-
-<p><strong>Headset Jack Functions</strong></p>
-<table>
- <tr>
- <th>
-<p><strong>Function</strong></p>
-</th>
- <th>
-<p><strong>Device Support</strong></p>
-</th>
- </tr>
- <tr>
- <td>
-<p>Stereo Audio Out</p>
-</td>
- <td>
-<p><strong>Required</strong></p>
-</td>
- </tr>
- <tr>
- <td>
-<p>Audio in (Mic)</p>
-</td>
- <td>
-<p><strong>Required</strong></p>
-</td>
- </tr>
- <tr>
- <td>
-<p>Ground</p>
-</td>
- <td>
-<p><strong>Required</strong></p>
-</td>
- </tr>
-</table>
-
-<h3 id=software_mapping>Software mapping</h3>
-
-<table>
- <tr>
- <th>
-<p><strong>Function</strong></p>
-</th>
- <th>
-<p><strong>Device Support</strong></p>
-</th>
- <th>
-<p><strong>Description</strong></p>
-</th>
- </tr>
- <tr>
- <td>
-<p>Function A control event </p>
-</td>
- <td>
-<p><strong>Required</strong></p>
-</td>
- <td>
-<p>input event KEY_MEDIA</p>
-
-<p>Android key KEYCODE_HEADSETHOOK</p>
-</td>
- </tr>
- <tr>
- <td>
-<p>Function D control event</p>
-</td>
- <td>
-<p><strong>Required</strong></p>
-</td>
- <td>
-<p>input event KEY_VOICECOMMAND</p>
-
-<p>Android key KEYCODE_VOICE_ASSIST</p>
-</td>
- </tr>
- <tr>
- <td>
-<p>Function B control event</p>
-</td>
- <td>
-<p><strong>Required</strong></p>
-</td>
- <td>
-<p>input event KEY_VOLUMEUP</p>
-
-<p>Android key VOLUME_UP</p>
-</td>
- </tr>
- <tr>
- <td>
-<p>Function C control event</p>
-</td>
- <td>
-<p><strong>Required</strong></p>
-</td>
- <td>
-<p>input event KEY_VOLUMEDOWN</p>
-
-<p>Android key VOLUME_DOWN</p>
-</td>
- </tr>
- <tr>
- <td>
-<p>Headset insertion detection</p>
-</td>
- <td>
-<p><strong>Required</strong></p>
-</td>
- <td>
-<p>input event SW_JACK_PHYSICAL_INSERT 7</p>
-</td>
- </tr>
- <tr>
- <td>
-<p>Headset type detection</p>
-</td>
- <td>
-<p><strong>Mic</strong></p>
-</td>
- <td>
-<p>input event SW_MICROPHONE_INSERT 4</p>
-</td>
- </tr>
- <tr>
- <td>
-<p>Headset type detection</p>
-</td>
- <td>
-<p><strong>No Mic</strong></p>
-</td>
- <td>
-<p>input event SW_HEADPHONE_INSERT 2</p>
-</td>
- </tr>
- <tr>
- <td>
-<p>Headset speaker impedance</p>
-</td>
- <td>
-<p><strong>Required Headphone (low)</strong></p>
-</td>
- <td>
-<p>Failure mode is to indicate headphones so that limitation would be on</p>
-</td>
- </tr>
- <tr>
- <td>
-<p>Headset speaker impedance</p>
-</td>
- <td>
-<p><strong>Required Line In (high)</strong></p>
-</td>
- <td>
-<p>input event SW_LINEOUT_INSERT 6</p>
-</td>
- </tr>
-</table>
-
-<h3 id=mechanical11>Mechanical</h3>
-
-<table>
- <tr>
- <th>
-<p><strong>Function</strong></p>
-</th>
- <th>
-<p><strong>Device Support</strong></p>
-</th>
- <th>
-<p><strong>Description</strong></p>
-</th>
- </tr>
- <tr>
- <td>
-<p>4 conductor 3.5mm jack</p>
-</td>
- <td>
-<p><strong>Required</strong></p>
-</td>
- <td></td>
- </tr>
- <tr>
- <td>
-<p>CTIA pinout order (LRGM)</p>
-</td>
- <td>
-<p><strong>Required</strong></p>
-</td>
- <td>
-<p>3 Pin & Mono Plug Compatible</p>
-</td>
- </tr>
- <tr>
- <td>
-<p>OMTP pinout order (LRMG)</p>
-</td>
- <td>
-<p>Optional but <strong>Strongly Recommended</strong></p>
-</td>
- <td></td>
- </tr>
- <tr>
- <td>
-<p>Headset detect sequence</p>
-</td>
- <td>
-<p><strong>Required</strong></p>
-</td>
- <td>
-<p>Plug insert notification must only be triggered after all contacts on plug are
-touching their relevant segments. This will prevent unreliable headset
-detection due to slow insertion. </p>
-</td>
- </tr>
-</table>
-
-<h3 id=electrical12>Electrical</h3>
-
-<h4 id=general>General</h4>
-
-<table>
- <tr>
- <th>
-<p><strong>Function</strong></p>
-</th>
- <th>
-<p><strong>Device Support</strong></p>
-</th>
- <th>
-<p><strong>Notes</strong></p>
-</th>
- </tr>
- <tr>
- <td>
-<p>Maximum output voltage drive</p>
-</td>
- <td>
-<p>150mV </p>
-</td>
- <td>
-<p>>= 150mV on 32 ohm</p>
-
-<p>Test conditions: EN50332-2</p>
-</td>
- </tr>
- <tr>
- <td>
-<p>Mic bias resistance </p>
-</td>
- <td>
-<p>Required</p>
-</td>
- <td>
-<p>Flexible on detection method used and microphone bias resistor selection.
-Require that all button resistance value ranges specified below be detected and
-related to their respective function</p>
-</td>
- </tr>
- <tr>
- <td>
-<p>Mic bias voltage</p>
-</td>
- <td>
-<p>1.8V - 2.9V</p>
-</td>
- <td>
-<p>To guarantee compatibility to common microphone capsules.</p>
-</td>
- </tr>
-</table>
-
-<h4 id=function_impedance_and_threshold_detection>Function Impedance and Threshold Detection</h4>
-
-<p>Devices must detect the following resistor ladder on the accessories. The
-accessories will be tested to the standardized circuit diagram in the diagram
-illustrated earlier (Reference Headset Test Circuit) where the total impedance
-is measured from MIC terminal to GND when a button is pressed with 2.2V mic
-bias applied through 2.2 kOhm resistor. This is the same effective resistance
-as the button detection circuit with the microphone in parallel with the button
-resistor.</p>
-<table>
- <tr>
- <th>
-<p><strong>Button Impedance Level</strong></p>
-</th>
- <th>
-<p><strong>Device Support</strong></p>
-</th>
- <th>
-<p><strong>Notes</strong></p>
-</th>
- </tr>
- <tr>
- <td>
-<p><strong>70 ohm or less</strong></p>
-</td>
- <td>
-<p><strong>Required</strong></p>
-</td>
- <td>
-<p>[Function A]</p>
-</td>
- </tr>
- <tr>
- <td>
-<p><strong>110 - 180 ohm </strong></p>
-</td>
- <td>
-<p><strong>Required</strong></p>
-</td>
- <td>
-<p>[Function D]</p>
-</td>
- </tr>
- <tr>
- <td>
-<p><strong>210 - 290 ohm</strong></p>
-</td>
- <td>
-<p><strong>Required</strong></p>
-</td>
- <td>
-<p>[Function B]</p>
-</td>
- </tr>
- <tr>
- <td>
-<p><strong>360 - 680 ohm </strong></p>
-</td>
- <td>
-<p><strong>Required</strong></p>
-</td>
- <td>
-<p>[Function C]</p>
-</td>
- </tr>
- <tr>
- <td>
-<p><strong>Headset speaker impedance level</strong></p>
-</td>
- <td></td>
- <td></td>
- </tr>
- <tr>
- <td>
-<p>Low Threshold Detection</p>
-</td>
- <td>
-<p><strong>Required</strong></p>
-</td>
- <td>
-<p>Headphone (low) < 1 Kohm</p>
-</td>
- </tr>
- <tr>
- <td>
-<p>High Threshold Detection</p>
-</td>
- <td>
-<p><strong>Required</strong></p>
-</td>
- <td>
-<p>Line In (high) > 5 Kohm</p>
-</td>
- </tr>
-</table>
diff --git a/src/accessories/headset/images/button_configuration.png b/src/accessories/headset/images/button_configuration.png
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diff --git a/src/accessories/headset/index.jd b/src/accessories/headset/index.jd
new file mode 100644
index 0000000..d66c6ac
--- /dev/null
+++ b/src/accessories/headset/index.jd
@@ -0,0 +1,29 @@
+page.title=Android Audio Headset
+@jd:body
+
+<!--
+ Copyright 2015 The Android Open Source Project
+
+ Licensed under the Apache License, Version 2.0 (the "License");
+ you may not use this file except in compliance with the License.
+ You may obtain a copy of the License at
+
+ http://www.apache.org/licenses/LICENSE-2.0
+
+ Unless required by applicable law or agreed to in writing, software
+ distributed under the License is distributed on an "AS IS" BASIS,
+ WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ See the License for the specific language governing permissions and
+ limitations under the License.
+-->
+
+<p>This section describes the development and testing of the Android headset
+accessory interface. This documentation presents the interface guidelines for the
+Android headset inline remote.</p>
+
+<p>The goal is to maintain certain standards for consistency and design while
+allowing for freedom in design expression. If you choose to implement a
+dedicated Android headset accessory, please follow these guidelines to ensure
+your headset is compatible with devices following the recommendations in the <a
+href="{@docRoot}compatibility/android-cdd.pdf">Android Compatibility Definition
+Document (CDD)</a>.</p>
diff --git a/src/accessories/headset/requirements.jd b/src/accessories/headset/requirements.jd
new file mode 100644
index 0000000..1f5c0d0
--- /dev/null
+++ b/src/accessories/headset/requirements.jd
@@ -0,0 +1,189 @@
+page.title=Headset Requirements
+@jd:body
+
+<!--
+ Copyright 2015 The Android Open Source Project
+
+ Licensed under the Apache License, Version 2.0 (the "License");
+ you may not use this file except in compliance with the License.
+ You may obtain a copy of the License at
+
+ http://www.apache.org/licenses/LICENSE-2.0
+
+ Unless required by applicable law or agreed to in writing, software
+ distributed under the License is distributed on an "AS IS" BASIS,
+ WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ See the License for the specific language governing permissions and
+ limitations under the License.
+-->
+<div id="qv-wrapper">
+ <div id="qv">
+ <h2>In this document</h2>
+ <ol id="auto-toc">
+ </ol>
+ </div>
+</div>
+
+<h2 id=media>Media</h2>
+
+<p>If a user connects a headset to the device while playing media, the audio
+output (sound) should be heard only via the headset.</p>
+
+<p>For example, while playing media with the <a
+href="https://github.com/googlesamples/android-UniversalMusicPlayer">open
+source</a> <a
+href="https://android-developers.blogspot.com/2015/03/a-new-reference-app-for-multi-device.html">Universal
+Music Player</a>, pressing the play/pause button should pause playback.
+Pressing the same button when media is paused should resume playback.</p>
+
+<p>If the headset has volume control buttons: </p>
+
+<ul>
+ <li> Pressing the volume-up button should increase the volume incrementally each
+time the button is pressed until maximum volume is reached. If the volume-up
+button is pressed and held, the volume should gradually increase to maximum
+volume setting.
+ <li> Pressing the volume-down button should decrease the volume incrementally each
+time the button is pressed until entirely muted. If the volume-down button is
+pressed and held, the volume should gradually decrease to silent.
+ <li> Pressing the volume-up button when in a muted state should increase the volume
+one notch at a time starting from silent.
+</ul>
+
+<p><strong>Recommended for Apps</strong>: On disconnecting the headset, sound output should stop and playback should
+pause. On reconnecting, playback should not start again unless the user presses
+the play button. Upon pressing play, sound output should again be limited to
+the headset.</p>
+
+<h3 id=one_button>One button</h3>
+
+<img src="images/media_one.png" alt="Button functions for one-button headsets handling a media stream.">
+</span>
+
+<p class="img-caption"><strong>Figure 1.</strong> Button functions for one-button headsets handling a media stream.</p>
+
+<h3 id=two_buttons>Two buttons</h3>
+
+<img src="images/media_two.png" alt="Button functions for two-button headsets handling a media stream.">
+
+<p class="img-caption"><strong>Figure 2.</strong> Button functions for two-button headsets handling a media stream.</p>
+
+<h3 id=three_buttons>Three buttons</h3>
+
+<img src="images/media_three.png" alt="Button functions for three-button headsets handling a media stream.">
+
+<p class="img-caption"><strong>Figure 3.</strong> Button functions for three-button headsets handling a media stream.</p>
+
+<h3 id=four_buttons>Four buttons</h3>
+
+<img src="images/media_four.png" alt="Button functions for four-button headsets handling a media stream.">
+
+<p class="img-caption"><strong>Figure 4.</strong> Button functions for four-button headsets handling a media stream.</p>
+
+<h2 id=telephony>Telephony</h2>
+
+
+<p>If a user connects a headset to the device while a call is in progress, the
+conversation should continue on the headset. The call should not get
+disconnected, and the microphone should not be muted. If present, volume
+buttons should behave identically to media playback.</p>
+
+<p>Pressing the play/pause button while a phone call is in progress should toggle
+the microphone state between muted and unmuted. If a user receives calls while
+using the headset, the voice assistance button should allow handling of those
+calls:</p>
+
+<ul>
+ <li> While in a phone call, pressing quickly on the play/pause button should mute
+the microphone. And if pressed quickly again, the microphone should un-mute.
+ <li> While in a phone call, a long press on the play/pause button should end the
+telephone call.
+ <li> While receiving a phone call, pressing quickly on the play/pause button should
+accept the call.
+ <li> While receiving a phone call, a long press on the play/pause button should
+reject the call.
+</ul>
+
+<h3 id=one_button>One button</h3>
+
+<img src="images/telephony_one.png" alt="Button functions for one-button headsets handling a phone call.">
+
+<p class="img-caption"><strong>Figure 5.</strong> Button functions for one-button headsets handling a phone call. </p>
+
+<h3 id=two_buttons>Two buttons</h3>
+
+<img src="images/telephony_two.png" alt="Button functions for two-button headsets handling a phone call.">
+
+<p class="img-caption"><strong>Figure 6.</strong> Button functions for two-button headsets handling a phone call. </p>
+
+<h3 id=three_buttons>Three buttons</h3>
+
+<img src="images/telephony_three.png" alt="Button functions for three-button headsets handling a phone call.">
+
+<p class="img-caption"><strong>Figure 7.</strong> Button functions for three-button headsets handling a phone call. </p>
+
+<h3 id=four_buttons>Four buttons</h3>
+
+<img src="images/telephony_four.png" alt="Button functions for four-button headsets handling a phone call.">
+<p class="img-caption"><strong>Figure 8.</strong> Button functions for four-button headsets handling a phone call. </p>
+
+<h2 id=voice_assistance>Voice assistance</h2>
+
+<p>The voice assistance button is a new inline control standard for consistently
+and conveniently accessing a voice search feature from any approved wearable
+audio device. By pressing the button defined here, users will hear the two-tone
+signature <a href="http://en.wikipedia.org/wiki/Earcon">earcon</a> indicating that the device is listening and ready to receive the query.</p>
+
+<p>Whether embedded into a multi-function button or highlighted as a single
+button, it should always be quickly accessible, ergonomically correct, and
+placed intuitively as described in the following section.</p>
+
+<h2 id=buttons_and_function_mapping>Buttons and function mapping recommendations</h2>
+
+<p>The following diagrams depict the acceptable configuration of the Android voice
+assistance button.</p>
+
+<h3 id=options>Options</h3>
+
+<img src="images/button_configuration.png" alt="Button configuration options.">
+
+<p class="img-caption"><strong>Figure 9.</strong> Button configuration options. </p>
+
+<p>Buttons should always be front facing and spaced out so they can be easily
+located by touch only.</p>
+
+<h3 id=spacing>Spacing</h3>
+
+<p>Buttons must be more than 5mm and must have at least 5mm distance between
+buttons. For four-button headsets, there must be at least 9mm of space between
+button D and the cluster of other buttons. </p>
+
+<img src="images/button_spacing.png" alt="Button spacing requirements">
+
+<p class="img-caption"><strong>Figure 10.</strong> Button spacing requirements.</p>
+
+<h3 id=icon>Icon</h3>
+
+<p>In the following diagram, A is unlabeled or labeled with a dot. B is labeled
+with a + or an arrow pointing up. C is labeled with a - or an arrow pointing
+down. D is labeled with the selected button icon.</p>
+
+<img src="images/button_icons.png" alt="Button icon requirements">
+<p class="img-caption"><strong>Figure 11.</strong> Button icon requirements. </p>
+
+<h3 id=sizing>Sizing</h3>
+
+<p>The following diagram shows the ratio of button icon to the space around it.</p>
+
+<img src="images/icon_sizing.png" alt="Voice search button icon sizing requirements">
+
+<p class="img-caption"><strong>Figure 12.</strong> Voice search button icon sizing requirements. </p>
+
+<h3 id=microphone_port>Microphone port</h3>
+
+<p>The microphone should never be obstructed when operating the buttons. Place the
+port away from finger interface area.</p>
+
+<img src="images/microphone.png" alt="Microphone placement">
+
+<p class="img-caption"><strong>Figure 13.</strong> Microphone placement. </p>
diff --git a/src/accessories/headset/specification.jd b/src/accessories/headset/specification.jd
new file mode 100644
index 0000000..d1616b1
--- /dev/null
+++ b/src/accessories/headset/specification.jd
@@ -0,0 +1,410 @@
+page.title=Wired Audio Headset Specification (v1.1)
+@jd:body
+
+<!--
+ Copyright 2015 The Android Open Source Project
+
+ Licensed under the Apache License, Version 2.0 (the "License");
+ you may not use this file except in compliance with the License.
+ You may obtain a copy of the License at
+
+ http://www.apache.org/licenses/LICENSE-2.0
+
+ Unless required by applicable law or agreed to in writing, software
+ distributed under the License is distributed on an "AS IS" BASIS,
+ WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ See the License for the specific language governing permissions and
+ limitations under the License.
+-->
+<div id="qv-wrapper">
+ <div id="qv">
+ <h2>In this document</h2>
+ <ol id="auto-toc">
+ </ol>
+ </div>
+</div>
+
+<p>This section specifies requirements for headsets and mobile devices to
+function uniformly across the Android ecosystem.</p>
+
+<h2 id="headset_accessory_plug_specifications">Headset accessory (plug)
+specifications</h2>
+
+<p>The following requirements apply to headset accessories.</p>
+
+<h3 id="functions">Functions</h3>
+
+<table style="width:50%">
+ <tr>
+ <th>Function</th>
+ <th>Accessory Support</th>
+ </tr>
+ <tr>
+ <td>Stereo Audio Out</td>
+ <td>Required</td>
+ </tr>
+ <tr>
+ <td>Audio in (Mic)</td>
+ <td>Required</td>
+ </tr>
+ <tr>
+ <td>Ground</td>
+ <td>Required</td>
+ </tr>
+</table>
+
+<h3 id="control-function_mapping">Control-function mapping</h3>
+
+<table>
+ <tr>
+ <th style="width:33%">Control Function</th>
+ <th style="width:33%">Accessory Support</th>
+ <th style="width:33%">Description</th>
+ </tr>
+ <tr>
+ <td>Function A</td>
+ <td>Required</td>
+ <td>Play/pause/hook (Short Press), Trigger Assist (Long Press), Next
+ (Double Press)</td>
+ </tr>
+ <tr>
+ <td>Function B</td>
+ <td>Optional</td>
+ <td>Vol+</td>
+ </tr>
+ <tr>
+ <td>Function C</td>
+ <td>Optional</td>
+ <td>Vol-</td>
+ </tr>
+ <tr>
+ <td>Function D</td>
+ <td>Optional</td>
+ <td>Reserved (Nexus devices use this to launch Voice Assist)
+</td>
+ </tr>
+</table>
+
+<p>Assign functions to buttons as follows:</p>
+
+<ul>
+ <li> All one-button headsets must implement Function A.
+ <li> Headsets with multiple buttons must implement functions according to the
+following pattern:
+ <ul>
+ <li> 2 functions: A and D
+ <li> 3 functions: A, B, C
+ <li> 4 functions: A, B, C, D
+ </ul>
+</ul>
+
+<h3 id="mechanical">Mechanical</h3>
+
+<table>
+ <tr>
+ <th style="width:33%">Function</th>
+ <th style="width:33%">Accessory Support</th>
+ <th style="width:33%">Notes</th>
+ </tr>
+ <tr>
+ <td>4 conductor 3.5mm plug</td>
+ <td>Required</td>
+ <td>Ref: EIAJ-RC5325A standard</td>
+ </tr>
+ <tr>
+ <td>CTIA pinout order (LRGM)</td>
+ <td>Required</td>
+ <td>Except in regions with legal requirements for OMTP pinout</td>
+ </tr>
+ <tr>
+ <td>OMTP pinout order (LRMG)</td>
+ <td>Optional</td>
+ <td></td>
+ </tr>
+ <tr>
+ <td>Microphone</td>
+ <td>Required</td>
+ <td>Must not be obstructed when operating headset controls</td>
+ </tr>
+</table>
+
+<h3 id="electrical">Electrical</h3>
+
+<table>
+ <tr>
+ <th style="width:33%">Function</th>
+ <th style="width:33%">Accessory Support</th>
+ <th style="width:33%">Description</th>
+ </tr>
+ <tr>
+ <td>Ear speaker impedance</td>
+ <td>16 ohms or higher</td>
+ <td>Recommend 32 - 300 ohms</td>
+ </tr>
+ <tr>
+ <td>Mic DC resistance</td>
+ <td>1000 ohms or higher
+</td>
+ <td>Mic characteristics must be compliant with section 5.4 “Audio
+ Recording” of the current
+ <a href="{@docRoot}compatibility/android-cdd.pdf">Android CDD</a></td>
+ </tr>
+ <tr>
+ <td rowspan="4">Control Function Equivalent impedance*</td>
+ <td>0 ohm</td>
+ <td>[Function A] Play/Pause/Hook</td>
+ </tr>
+ <tr>
+ <td>240 ohm +/- 1% resistance</td>
+ <td>[Function B]</td>
+ </tr>
+ <tr>
+ <td>470 ohm +/- 1% resistance</td>
+ <td>[Function C]</td>
+ </tr>
+ <tr>
+ <td>135 ohm +/- 1% resistance</td>
+ <td>[Function D]</td>
+ </tr>
+</table>
+
+<p><em>*Total impedance from positive mic terminal to GND when button is
+pressed with 2.2 V mic bias applied through 2.2 kOhm resistor</em></p>
+
+<p>In the following diagrams, Button A maps to Function A, Button B to
+Function B, and so on.</p>
+
+<h3 id="reference_headsets">Reference headset test circuits</h3>
+
+<p>The following diagram for Reference Headset Test Circuit 1 shows the CTIA
+pinout for a 4-segment plug. For the OMTP pinout, switch the positions of the
+MIC and GND segments.</p>
+
+<img src="images/headset-circuit1.png" alt="Reference Headset Test Circuit 1" />
+<p class="img-caption"><strong>Figure 1.</strong> Reference headset test circuit 1</p>
+
+<p>The following diagram for Reference Headset Test Circuit 2 shows how the
+actual resistor values (R1 - R4) are altered to meet this specification.</p>
+
+<img src="images/headset-circuit2.png" alt="Reference Headset Test Circuit 2" />
+<p class="img-caption"><strong>Figure 2.</strong> Reference headset test circuit 2</p>
+
+<p>The actual resistance of the buttons parallel with the microphone (R1-R4) is
+based on the microphone capsule resistance (Rmic) and the equivalent impedance
+values (ReqA-ReqD). Use the following formula:</p>
+
+<p><em>Rn=(Rmic*ReqN) / (ReqN-Rmic)</em></p>
+
+<p>Where R<em>n</em> is the actual resistance of a button, Req<em>N</em> is the
+equivalent impedance value of that button (provided), and Rmic is the
+microphone impedance value.</p>
+
+<p>The example above assumes a 5 kohm microphone impedance (Rmic); to achieve
+an equivalent R4 impedance of 135 ohm (ReqD), the actual resistor value (R4)
+must be 139 ohms.</p>
+
+<h2 id="mobile_device_jack_specifications">Mobile device (jack) specifications</h2>
+
+<p class="caution"><strong>Caution:</strong> To achieve compatibility with the
+headset specification, devices that include a 4 conductor 3.5mm audio jack
+must meet the following specifications. For Android compatibility requirements,
+refer to the <em>Analog audio ports</em> section of the <a
+href="{@docRoot}compatibility/android-cdd.pdf">Android CDD</a>.</p>
+
+<h3 id="headset_jack_functions">Functions</h3>
+
+<table>
+ <tr>
+ <th>Function</th>
+ <th>Device Support</th>
+ </tr>
+ <tr>
+ <td>Stereo Audio Out</td>
+ <td>Required</td>
+ </tr>
+ <tr>
+ <td>Audio in (Mic)</td>
+ <td>Required</td>
+ </tr>
+ <tr>
+ <td>Ground</td>
+ <td>Required</td>
+ </tr>
+</table>
+
+<h3 id="software_mapping">Software mapping</h3>
+
+<table>
+ <tr>
+ <th style="width:33%">Function</th>
+ <th style="width:33%">Device Support</th>
+ <th style="width:33%">Description</th>
+ </tr>
+ <tr>
+ <td>Function A control event</td>
+ <td>Required</td>
+ <td>input event KEY_MEDIA
+<p>Android key KEYCODE_HEADSETHOOK</p></td>
+ </tr>
+ <tr>
+ <td>Function D control event</td>
+ <td>Required</td>
+ <td>input event KEY_VOICECOMMAND
+<p>Android key KEYCODE_VOICE_ASSIST</p></td>
+ </tr>
+ <tr>
+ <td>Function B control event</td>
+ <td>Required
+</td>
+ <td>input event KEY_VOLUMEUP
+<p>Android key VOLUME_UP</p></td>
+ </tr>
+ <tr>
+ <td>Function C control event</td>
+ <td>Required</td>
+ <td>input event KEY_VOLUMEDOWN
+<p>Android key VOLUME_DOWN</p></td>
+ </tr>
+ <tr>
+ <td>Headset insertion detection</td>
+ <td>Required</td>
+ <td>input event SW_JACK_PHYSICAL_INSERT 7</td>
+ </tr>
+ <tr>
+ <td rowspan="2">Headset type detection</td>
+ <td>Mic</td>
+ <td>input event SW_MICROPHONE_INSERT 4</td>
+ </tr>
+ <tr>
+ <td>No Mic</td>
+ <td>input event SW_HEADPHONE_INSERT 2</td>
+ </tr>
+ <tr>
+ <td rowspan="2">Headset speaker impedance</td>
+ <td>Required Headphone (low)</td>
+ <td>Failure mode is to indicate headphones so limitation would be on</td>
+ </tr>
+ <tr>
+ <td>Required Line In (high)</td>
+ <td>input event SW_LINEOUT_INSERT 6</td>
+ </tr>
+</table>
+
+<h3 id="mechanical11">Mechanical</h3>
+
+<table>
+ <tr>
+ <th style="width:33%">Function</th>
+ <th style="width:33%">Device Support</th>
+ <th style="width:33%">Description</th>
+ </tr>
+ <tr>
+ <td>4 conductor 3.5mm jack</td>
+ <td>Required</td>
+ <td></td>
+ </tr>
+ <tr>
+ <td>CTIA pinout order (LRGM)</td>
+ <td>Required</td>
+ <td>3 Pin & Mono Plug Compatible</td>
+ </tr>
+ <tr>
+ <td>OMTP pinout order (LRMG)</td>
+ <td>Optional but strongly recommended</td>
+ <td></td>
+ </tr>
+ <tr>
+ <td>Headset detect sequence</td>
+ <td>Required</td>
+ <td>Plug insert notification must be triggered only after all contacts on
+ plug are touching their relevant segments (this prevents unreliable headset
+ detection due to slow insertion.</td>
+ </tr>
+</table>
+
+<h3 id="electrical12">Electrical</h3>
+
+<h4 id="general">General</h4>
+
+<table>
+ <tr>
+ <th style="width:33%">Function</th>
+ <th style="width:33%">Device Support</th>
+ <th style="width:33%">Notes</th>
+ </tr>
+ <tr>
+ <td>Maximum output voltage drive</td>
+ <td>150mV</td>
+ <td>>= 150mV on 32 ohm
+<p>Test conditions: EN50332-2</p></td>
+ </tr>
+ <tr>
+ <td>Mic bias resistance</td>
+ <td>Required</td>
+ <td>Flexible on detection method used and microphone bias resistor
+ selection. Require that all button resistance value ranges specified below
+ be detected and related to their respective function</td>
+ </tr>
+ <tr>
+ <td>Mic bias voltage</td>
+ <td>1.8V - 2.9V</td>
+ <td>To guarantee compatibility to common microphone capsules.</td>
+ </tr>
+</table>
+
+<h4 id="function_impedance_and_threshold_detection">Function impedance and
+threshold detection</h4>
+
+<p>Devices must detect the following resistor ladder on the accessories. The
+accessories will be tested to the standardized circuit diagram in the diagram
+illustrated earlier (Reference Headset Test Circuit) where the total impedance
+is measured from MIC terminal to GND when a button is pressed with 2.2V mic
+bias applied through 2.2 kOhm resistor. This is the same effective resistance
+as the button detection circuit with the microphone in parallel with the button
+resistor.</p>
+
+<table>
+ <tr>
+ <th style="width:40%">Button Impedance Level</th>
+ <th style="width:20%">Device Support</th>
+ <th style="width:40%">Notes</th>
+ </tr>
+ <tr>
+ <td>70 ohm or less</td>
+ <td>Required</td>
+ <td>[Function A]</td>
+ </tr>
+ <tr>
+ <td>110 - 180 ohm</td>
+ <td>Required</td>
+ <td>[Function D]</td>
+ </tr>
+ <tr>
+ <td>210 - 290 ohm</td>
+ <td>Required</td>
+ <td>[Function B]</td>
+ </tr>
+ <tr>
+ <td>360 - 680 ohm</td>
+ <td>Required</td>
+ <td>[Function C]</td>
+ </tr>
+ </table>
+
+ <table>
+ <tr>
+ <th style="width:40%">Headset Speaker Impedance Level</th>
+ <th style="width:20%">Device Support</th>
+ <th style="width:40%">Notes</th>
+ </tr>
+ <tr>
+ <td>Low Threshold Detection</td>
+ <td>Required</td>
+ <td>Headphone (low) < 1 Kohm</td>
+ </tr>
+ <tr>
+ <td>High Threshold Detection</td>
+ <td>Required</td>
+ <td>Line In (high) > 5 Kohm</td>
+ </tr>
+</table>
diff --git a/src/accessories/headset/testing.jd b/src/accessories/headset/testing.jd
new file mode 100644
index 0000000..c66d4f0
--- /dev/null
+++ b/src/accessories/headset/testing.jd
@@ -0,0 +1,112 @@
+page.title=Testing
+@jd:body
+
+<!--
+ Copyright 2015 The Android Open Source Project
+
+ Licensed under the Apache License, Version 2.0 (the "License");
+ you may not use this file except in compliance with the License.
+ You may obtain a copy of the License at
+
+ http://www.apache.org/licenses/LICENSE-2.0
+
+ Unless required by applicable law or agreed to in writing, software
+ distributed under the License is distributed on an "AS IS" BASIS,
+ WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ See the License for the specific language governing permissions and
+ limitations under the License.
+-->
+<div id="qv-wrapper">
+ <div id="qv">
+ <h2>In this document</h2>
+ <ol id="auto-toc">
+ </ol>
+ </div>
+</div>
+
+<h2 id=headset_insertion>Headset insertion</h2>
+
+<ol>
+ <li> Start with the Android device turned off.
+ <li> Plug in the headset.
+ <li> Turn the device on.
+ <li> Unlock.
+ <li> Open the <a
+ href="https://github.com/googlesamples/android-UniversalMusicPlayer">open
+ source</a> <a
+ href="https://android-developers.blogspot.com/2015/03/a-new-reference-app-for-multi-device.html">Universal
+ Music Player</a>.
+ <li> Press the DUT volume buttons to maximize media volume.
+ <li> Start playing music and verify audio comes out of the headset.
+ <li> While Music is playing, disconnect the headset and verify music stops.
+ <li> Reconnect the headset, start playing music again, and verify audio comes out of
+the headset.
+</ol>
+
+<h2 id=volume_buttons>Volume buttons</h2>
+
+<ol>
+ <li> Play music and ensure it is coming out of the headset.
+ <li> Press (“short press”) on the volume-down button. Then verify the volume panel
+displays the media volume decrease by one notch and the volume output is
+reduced as expected.
+ <li> Long press on the volume-down button. Then verify the volume panel shows media
+volume going all the way down and volume output is reduced gradually to muted.
+ <li> Press on the volume-up button. Then verify the volume panel displays the media
+volume go up one notch and the volume output is increased as expected.
+ <li> Long press on the volume-up button. Then verify the volume panel shows the
+media volume go all the way up to maximum and the volume output is increased as
+expected.
+</ol>
+
+<h2 id=play_pause_for_music>Play/pause for music</h2>
+
+<p>Press quickly on the play/pause button and verify music stops playing out of
+the headset. If music was not already playing, then it should start playing out
+of the headset.</p>
+
+<h2 id=play_pause_for_telephony>Play/pause for telephony</h2>
+
+<ol>
+ <li> Make a phone call.
+ <li> Press quickly on the play/pause button while in the call.
+ <li> Verify the microphone mutes. And if you press quickly again, the microphone
+should un-mute.
+ <li> While still in the call, long press on the play/pause button.
+ <li> Verify the long press ends the telephone call
+ <li> Receive a phone call on the Android device.
+ <li> Press quickly on the play/pause button while the phone is ringing and verify
+the call is accepted.
+ <li> Receive another phone call on the Android device.
+ <li> Long press on the play/pause button while the phone is ringing and verify the
+call is rejected.
+</ol>
+
+<h2 id=play_pause_for_voice_actions_microphone>Play/pause for voice actions + microphone</h2>
+
+<ol>
+ <li> Open the screen on your Android device, unlock it, and go to the home screen.
+ <li> Long press on the play/pause button.
+ <li> Verify:
+ <ol>
+ <li> you hear a beep after which you should be able to make a voice search query,
+such as “What time is it?”
+ <li> you hear a response, such as “The time is ...”
+ </ol>
+ </ol>
+
+<h2 id=voice_button_for_voice_actions_microphone>Voice button for voice actions + microphone</h2>
+
+<ol>
+ <li> Open the screen on your Android device, unlock it, and go to the home screen.
+ <li> Short press on the voice button.
+ <li> Verify:
+ <ol>
+ <li> you hear a beep after which you should be able to make a search query, such as
+“What time is it?”
+ <li> you hear a response, such as “The time is ...”
+ </ol>
+ </ol>
+
+<p><strong>Important</strong>: A press on the voice button can launch launch any search app, for example
+Google search.</p>
diff --git a/src/accessories/index.jd b/src/accessories/index.jd
index d30c0ce..709b26a 100644
--- a/src/accessories/index.jd
+++ b/src/accessories/index.jd
@@ -2,7 +2,7 @@
@jd:body
<!--
- Copyright 2014 The Android Open Source Project
+ Copyright 2015 The Android Open Source Project
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
@@ -16,10 +16,8 @@
See the License for the specific language governing permissions and
limitations under the License.
-->
-<p>Implement compelling accessories to extend the capabilities of your users'
-Android-powered devices. Android relies on a suite of standard protocols you
-can implement in your accessories to be compatible with a wide range of
-Android-powered devices.
+<p>Using a suite of standard protocols, you can implement compelling accessories
+that extend Android capabilities in a wide range of Android-powered devices.
</p>
<div class="layout-content-row">
@@ -29,8 +27,8 @@
<p>Android supports local on-device audio and remote off-device audio
over a wired 3.5 mm headset jack, USB connection, or Bluetooth.
Manufacturers should see the <a
- href="{@docRoot}accessories/headset-spec.html">wired audio headset
- specification</a>, while users may learn how to <a
+ href="{@docRoot}accessories/headset/specification.html">wired audio headset
+ specification</a>, while users can learn how to <a
href="https://support.google.com/nexus/answer/6127700">record and play
back audio using USB host mode</a>.</p>
<p><a href="{@docRoot}accessories/audio.html">» Audio Accessories</a></p>
@@ -38,9 +36,10 @@
<div class="layout-content-col span-6">
<h4 id="custom-accessories">Custom Accessories</h4>
- <p>What do you want to connect to your Android device? Alarm clock? Keyboard? Thermostat? Robot?
- Learn how to connect existing equipment or your own unique hardware to
- Android using the Android Open Accessory Protocol.</p>
+ <p>What do you want to connect to your Android device? Alarm clock?
+ Keyboard? Thermostat? Robot? Learn how to connect existing equipment or
+ your own unique hardware to Android using the Android Open Accessory
+ (AOA) protocol.</p>
<p><a href="{@docRoot}accessories/custom.html">» Custom Accessories</a></p>
</div>
diff --git a/src/accessories/protocol.jd b/src/accessories/protocol.jd
index 7ce3bb4..b04e634 100644
--- a/src/accessories/protocol.jd
+++ b/src/accessories/protocol.jd
@@ -1,44 +1,52 @@
-page.title=Android Open Accessory Protocol
+page.title=Android Open Accessory (AOA)
@jd:body
<!--
- Copyright 2013 The Android Open Source Project
+ Copyright 2015 The Android Open Source Project
- Licensed under the Apache License, Version 2.0 (the "License");
- you may not use this file except in compliance with the License.
- You may obtain a copy of the License at
+ Licensed under the Apache License, Version 2.0 (the "License");
+ you may not use this file except in compliance with the License.
+ You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
- Unless required by applicable law or agreed to in writing, software
- distributed under the License is distributed on an "AS IS" BASIS,
- WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- See the License for the specific language governing permissions and
- limitations under the License.
+ Unless required by applicable law or agreed to in writing, software
+ distributed under the License is distributed on an "AS IS" BASIS,
+ WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ See the License for the specific language governing permissions and
+ limitations under the License.
-->
-<p> Android Open Accessory support allows external USB hardware (an Android USB accessory) to interact
-with an Android-powered device in a special accessory mode. When an Android-powered powered device
-is in accessory mode, the connected accessory acts as the USB host (powers the bus and enumerates
-devices) and the Android-powered device acts in the USB accessory role. Android USB accessories are
-specifically designed to attach to Android-powered devices and adhere to the Android Open Accessory
-Protocol, that allows them to detect Android-powered devices that support
-accessory mode. Accessories must also provide 500mA at 5V for charging power. Many previously
-released Android-powered devices are only capable of acting as a USB device and cannot initiate
-connections with external USB devices. Android Open Accessory support overcomes this limitation
-and allows you to build accessories that can interact with an assortment of Android-powered
-devices by allowing the accessory to initiate the connection.</p>
+<p>Android Open Accessory (AOA) support allows external USB hardware
+(Android USB accessories) to interact with Android-powered devices in
+<em>accessory mode</em>. When an Android-powered powered device is in
+accessory mode, the connected accessory acts as the USB host (powers the bus and
+enumerates devices) and the Android-powered device acts as the USB accessory.
+</p>
+<p>Android USB accessories are designed to attach to Android-powered devices.
+Such accessories adhere to AOA, enabling them to detect Android-powered devices
+that support accessory mode, and must provide 500mA at 5V for charging power.
+Some previously-released Android-powered devices are capable of acting only
+as a USB device and cannot initiate connections with external USB devices. AOA
+support overcomes this limitation, enabling you to build accessories that can
+initiate connections and interact with an assortment of Android-powered devices.
+</p>
-<p><strong>Note:</strong> Accessory mode is ultimately dependent on the device's hardware and not all devices
-support accessory mode. Devices that support accessory mode can be filtered using a <code><uses-feature></code>
-element in your corresponding application's Android manifest. For more information, see the
-<a href="http://developer.android.com/guide/topics/connectivity/usb/accessory.html#manifest">USB Accessory</a>
-developer guide.</p>
-
+<p class="note"><strong>Note:</strong> Accessory mode is dependent on device
+hardware; not all devices support accessory mode. Devices that support accessory
+mode can be filtered using a <code><uses-feature></code> element in the
+corresponding application's Android manifest. For details, see the
+<a href="http://developer.android.com/guide/topics/connectivity/usb/accessory.html#manifest">USB
+Accessory</a> developer guide.</p>
-<p>Android Open Accessory support is included in Android 3.1 (API Level 12) and higher, and supported
-through an <a href="https://developers.google.com/android/add-ons/google-apis/">Add-On Library</a> in Android
-2.3.4 (API Level 10) and higher.</p>
-
-
+<p>AOA has two versions that support different types of communication:</p>
+<ul>
+<li><strong>AOAv1</strong>. Supports generic accessory communication and adb
+debugging. Available in Android 3.1 (API Level 12) and higher and supported
+through an
+<a href="https://developers.google.com/android/add-ons/google-apis/">Add-On
+Library</a> in Android 2.3.4 (API Level 10) and higher.</li>
+<li><strong>AOAv2</strong>. Supports audio streaming and human interface
+device (HID) capabilities. Available in Android 4.1 (API Level 16).</li>
+</ul>
\ No newline at end of file
