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     <title>USB Audio CTS Verifier Tests</title>
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 <p>
 Several <a href="/compatibility/cts/">Android Compatibility Test Suite (CTS)</a>
 tests for <a href="https://source.android.com/devices/audio/usb">Android USB audio</a>
 require human intervention and the physical connection of USB audio
 peripherals. For these, additional CTS Verifier tests have been implemented.
 The requirements and protocols for these tests are explained in this document.
 </p>

 <h2 id="nomenclature">Nomenclature</h2>

 <p>
 Throughout this document, the term "device" and "peripheral" are used in a very
 precise manner:
 </p>
 <ul>
 <li><em>Device</em> refers to the Android device.</li>
 <li><em>Peripheral</em> is used to denote an external USB audio peripheral
 connected to the Android device.</li>
 </ul>

 <h2 id="recommended-peripherals">Recommended peripherals</h2>

 <p>
 In order for the USB audio CTS Verifier Tests to know the attributes and
 capabilities they are verifying, it is necessary to specify a set of known
 peripherals to test against. For this reason, specific brands and types are
 recommended below. Successful completion of the tests requires one peripheral of
 each category of peripherals specified below. Use of other types will cause the
 tests to fail.
 </p>

 <h3 id="usb-audio-interface">USB audio interface</h3>

 <p class="note"><strong>Note:</strong> This list is preliminary and subject to change.</p>

 <ul>
 <li><a href="http://www.presonus.com/products/audiobox-22VSL">Presonus AudioBox
 22VSL</a></li>
 <li><a href="https://www.presonus.com/products/audiobox-usb">Presonus AudioBox
 USB</a></li>
 </ul>

 <table>
   <tr>
    <td width="50%">A USB audio interface (A PreSonus AudioBox 22VSL)
    </td>
    <td width="50%"><img src="/compatibility/cts/images/usb_audio_interface.png" alt="USB audio interface" width="300"
         id="usb_audio_interface" /></td>
   </tr>
 </table>

 <h3 id="usb-headset">USB headset</h3>

 <p class="note"><strong>Note:</strong> This list is preliminary and subject to change.</p>

 <table>
   <tr>
    <td width="50%">A USB headset
    </td>
     <td width="50%"><img src="/compatibility/cts/images/usb_headset.png" alt="USB headset" width="300"
         id="usb_headset" /></td>
   </tr>
 </table>

 <h3 id="peripheral-profiles">Peripheral profiles</h3>

 <p>
 The USB Audio CTS Verifier Tests "know about" these recommended peripherals
 through built-in profiles provided by Android that describe the attributes and
 capabilities of a peripheral. When the peripheral is connected to the Android
 device under test, the correct profile is automatically selected.
 </p>

 <h2 id="required-additional-hardware">Required additional hardware</h2>

 <p>Patch cables (for loopback)
 2 short ¼" male to ¼" male patch cables to
 connect the outputs to the inputs of the USB</p>

 <table>
   <tr>
    <td width="50%">
    ¼" male to ¼" male patch cables
    </td>
       <td width="50%"><img src="/compatibility/cts/images/patch_cables.png" alt="patch cables" width="300"
         id="patch_cables" /></td>
    </td>
   </tr>
 </table>

 <p>USB peripheral cable</p>

 <table>
   <tr>
    <td width="50%">This cable (which typically comes with the peripheral), connects the USB
 audio peripheral to the host device
    </td>
    </td>
       <td width="50%"><img src="/compatibility/cts/images/peripheral_cable.png" alt="peripheral cable" width="300"
         id="peripheral_cable" /></td>
    </td>
   </tr>
 </table>

 <p>USB "On The Go" (OTG) adapter</p>

 <table>
   <tr>
    <td width="50%">A USB "On The Go" (OTG) adapter is required to physically connect the
 peripheral to the Android device and indicate to the Android device that it
 should assume the role of "host"
    </td>
    </td>
       <td width="50%"><img src="/compatibility/cts/images/otg_adapter.png" alt="OTG adapter" width="300"
         id="otg_adapter" /></td>
    </td>
   </tr>
 </table>

 <p>Analog headphones to monitor the output of the USB audio interface for the
 Play test.</p>

 <table>
   <tr>
    <td width="50%">Set of analog headphones.
    </td>
    </td>
       <td width="50%"><img src="/compatibility/cts/images/analog_headphones.png" alt="analog headphones" width="300"
         id="analog_headphones" /></td>
    </td>
   </tr>
 </table>

 <h2 id="tests">Tests</h2>

 <p>
 In each test, indicate test success by clicking the <strong>test pass</strong>
 (check mark) button. Otherwise, indicate test failure by clicking the
 <strong>test fail</strong> (exclamation point) button.
 </p>

 <h3 id="attributes-test">Attributes test</h3>

 <h4 id="abstract">Abstract</h4>

 <p>
 This test verifies that the attributes (supported sample-rates, channel
 configurations, sample formats…) match the set of a-priori known attributes of
 the device.
 </p>

 <h4 id="process">Process</h4>

 <p>
 After invoking the test from the main menu, connect a USB audio peripheral. If
 the attributes match, the <strong>test pass</strong> (check mark) button will be
 enabled. Click the <strong>test pass</strong> button to indicate success. If the
 attributes do not match, indicate test failure by clicking the <strong>test
 fail</strong> (exclamation point) button.
 </p>

 <table>
   <tr>
    <td width="50%">Select <em>USB Audio Peripheral Attributes Test</em>.
    </td>
       <td width="50%"><img src="/compatibility/cts/images/attributes_test.png" alt="attributes test" width="300"
         id="attributes test" /></td>
   </tr>
   <tr>
    <td width="50%">Summary of instructions is displayed
    </td>
       <td width="50%"><img src="/compatibility/cts/images/attributes_summary.png" alt="attributes summary" width="300"
         id="attributes_summary" /></td>
   </tr>
   <tr>
    <td width="50%">Pre-connect screen
    </td>
       <td width="50%"><img src="/compatibility/cts/images/attributes_preconnect.png" alt="attributes
        preconnect" width="300"
         id="attributes_preconnect" /></td>
   </tr>
   <tr>
    <td width="50%">USB audio peripheral connected to Android Device with peripheral cable
 and OTG adapter
    </td>
       <td width="50%"><img src="/compatibility/cts/images/attributes_connected.png" alt="attributes connected" width="300"
         id="attributes_connected" /></td>
   </tr>
   <tr>
    <td width="50%">Post-connect screen
    </td>
       <td width="50%"><img src="/compatibility/cts/images/attributes_postconnect.png" alt="attributes post connection" width="300"
         id="attributes_postconnect" /></td>
   </tr>
 </table>

 <h3 id="play-test">Play test</h3>

 <h4 id="abstract">Abstract</h4>

 <p>
 This test verifies that audio playback is functioning. It does this by
 generating a 1KHz test tone and presenting it in stereo (two-channels) to the
 USB audio peripheral.
 </p>

 <h4 id="process">Process</h4>

 <p>
 After invoking the test from the main menu, connect the USB audio interface,
 including the analog headset to the headset output jack on the interface (for
 monitoring).
 </p>

 <p>
 Press the <strong>PLAY</strong> button. If the test tone is heard in both
 channels of the headset, indicate test pass by clicking the <strong>test
 pass</strong> (check mark) button. If either or both of the channels do not play
 the tone, indicate test failure by clicking the <strong>test fail</strong>
 (exclamation point) button.
 </p>

 <h4 id="notes">Notes</h4>

 <table>
   <tr>
    <td width="50%">Select <em>USB Audio Peripheral Play Test</em>
    </td>
       <td width="50%"><img src="/compatibility/cts/images/play_test.png" alt="play test" width="300"
         id="play_test" /></td>
   </tr>
   <tr>
    <td width="50%">Summary of instructions is displayed
    </td>
       <td width="50%"><img src="/compatibility/cts/images/play_summary.png" alt="play summary" width="300"
         id="play_summary" /></td>
   </tr>
   <tr>
    <td width="50%">Pre-connect screen
    </td>
       <td width="50%"><img src="/compatibility/cts/images/play_preconnect.png" alt="play preconnect" width="300"
         id="play_preconnect" /></td>
   </tr>
   <tr>
    <td width="50%">Connect the USB audio peripheral to the Android Device
 <p>
 The headphones are connected to the headphone output jack on the USB audio
 interface for monitoring
    </td>
       <td width="50%"><img src="/compatibility/cts/images/play_connected.png" alt="play connected" width="300"
         id="play_connected" /></td>
   </tr>
   <tr>
    <td width="50%">Post-connect screen
    </td>
       <td width="50%"><img src="/compatibility/cts/images/play_postconnect.png" alt="play post connection" width="300"
         id="play_postconnect" /></td>
   </tr>
 </table>


 <h3 id="record-loopback-test">Record (loopback) test</h3>

 <h4 id="abstract">Abstract</h4>

 <p>
 This test verifies that audio recording is functioning. It does this by
 generating a tone at the outputs of the USB audio interface, which is then
 routed via patch cords to the inputs of the USB audio peripheral.
 </p>

 <h4 id="process">Process</h4>

 <p>
 After invoking the test from the main menu, connect the USB audio interface.
 Connect the analog outputs to the analog inputs with patch cables. Press the
 <strong>RECORD LOOPBACK</strong> button. If both the channels of the recorded
 test tone are shown in the view below, indicate test pass by clicking the
 <strong>test pass</strong> (check mark) button. If either or both of the
 channels does not display, indicate test failure by clicking the <strong>test
 fail</strong> (exclamation point) button.
 </p>

 <h4 id="notes">Notes</h4>

 <p>
 Ensure positive connection of both input and output jacks on the peripheral. It
 will be necessary to adjust the input levels to correctly display the recorded
 signal.
 </p>

 <table>
   <tr>
    <td width="50%">Select <em>USB Audio Peripheral Record Test</em>
    </td>
       <td width="50%"><img src="/compatibility/cts/images/record_test.png" alt="record test" width="300"
         id="record_test" /></td>
   </tr>
   <tr>
    <td width="50%">Summary of instructions is displayed
    </td>
       <td width="50%"><img src="/compatibility/cts/images/record_summary.png" alt="record summary" width="300"
         id="record_summary" /></td>
   </tr>
   <tr>
    <td width="50%">Pre-connect screen
    </td>
       <td width="50%"><img src="/compatibility/cts/images/record_preconnect.png" alt="record preconnect" width="300"
         id="record_preconnect" /></td>
   </tr>
   <tr>
    <td width="50%">USB audio Interface with loopback connected to Android device
    </td>
       <td width="50%"><img src="/compatibility/cts/images/record_connected.png" alt="record connected" width="300"
         id="record_connected" /></td>
   </tr>
   <tr>
    <td width="50%">Connections on the back of the USB audio interface
    </td>
       <td width="50%"><img src="/compatibility/cts/images/record_connected_back.png" alt="record connected in back" width="300"
         id="record_connected_back" /></td>
   </tr>
   <tr>
    <td width="50%">Connections on the front of the USB audio interface
    </td>
       <td width="50%"><img src="/compatibility/cts/images/record_connected_front.png" alt="record connected in front" width="300"
         id="record_connected_front" /></td>
   </tr>
   <tr>
    <td width="50%">Post-connect screen, with record test running
    </td>
       <td width="50%"><img src="/compatibility/cts/images/record_postconnect.png" alt="record post connection" width="300"
         id="record_postconnect" /></td>
   </tr>
 </table>
 <h3></h3>
 <h3 id="headset-buttons-test">Headset buttons test</h3>
 <h4 id="abstract">Abstract</h4>
 <p>
 This test verifies the <strong>media/transport </strong>buttons on the
 recommended headset are correctly recognized.
 </p>
 <h4 id="process">Process</h4>
 <p>
 After invoking the test from the main menu, connect the USB headset peripheral.
 Press each <strong>media/transport</strong> (play, pause, volume up & volume
 down) button on the headset. As each is recognized, it will be recognized in the
 test panel. When all buttons have been recognized, the <strong>test
 pass</strong> (check mark) button will be enabled. Click the <strong>test
 pass</strong> button to indicate success. If the full set of buttons is not
 recognized, indicate test failure by clicking the <strong>test fail</strong>
 (exclamation point) button.
 </p>
 <h4 id="notes">Notes</h4>
 <table>
   <tr>
    <td width="50%">The USB headset peripheral connected to the Android device
 <p>
 Note the OTG adapter
    </td>
       <td width="50%"><img src="/compatibility/cts/images/buttons_connected.png" alt="buttons connected" width="300"
         id="buttons_connected" /></td>
   </tr>
   <tr>
    <td width="50%">Select <em>USB Audio Peripheral Buttons Test</em>
    </td>
       <td width="50%"><img src="/compatibility/cts/images/buttons_test.png" alt="buttons test" width="300"
         id="buttons_test" /></td>
   </tr>
   <tr>
    <td width="50%">Summary of instructions is displayed
    </td>
       <td width="50%"><img src="/compatibility/cts/images/buttons_summary.png" alt="buttons summary" width="300"
         id="buttons_summary" /></td>
   </tr>
   <tr>
    <td width="50%">Peripheral connected, but no buttons recognized (yet)
 <p>
 Note that the expected (buttons which are known to the device profile) are
 indicated with with white text; those that are not part of the test peripheral
 are displayed in grey text
    </td>
       <td width="50%"><img src="/compatibility/cts/images/buttons_not_recognized.png" alt="buttons not recognized" width="300"
         id="buttons not recognized" /></td>
   </tr>
   <tr>
    <td width="50%">Peripheral connected, and expected buttons recognized
    </td>
       <td width="50%"><img src="/compatibility/cts/images/buttons_recognized.png" alt="buttons recognized" width="300"
         id="buttons recognized" /></td>
   </tr>
 </table>

 </body>
 </html>
	<html devsite>
	<head>
	<title>USB Audio CTS Verifier Tests</title>
	<meta name="project_path" value="/_project.yaml" />
	<meta name="book_path" value="/_book.yaml" />
	</head>
	<body>
	<!--
	Copyright 2017 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>
	Several <a href="/compatibility/cts/">Android Compatibility Test Suite (CTS)</a>
	tests for <a href="https://source.android.com/devices/audio/usb">Android USB audio</a>
	require human intervention and the physical connection of USB audio
	peripherals. For these, additional CTS Verifier tests have been implemented.
	The requirements and protocols for these tests are explained in this document.
	</p>

	<h2 id="nomenclature">Nomenclature</h2>

	<p>
	Throughout this document, the term "device" and "peripheral" are used in a very
	precise manner:
	</p>
	<ul>
	<li><em>Device</em> refers to the Android device.</li>
	<li><em>Peripheral</em> is used to denote an external USB audio peripheral
	connected to the Android device.</li>
	</ul>

	<h2 id="recommended-peripherals">Recommended peripherals</h2>

	<p>
	In order for the USB audio CTS Verifier Tests to know the attributes and
	capabilities they are verifying, it is necessary to specify a set of known
	peripherals to test against. For this reason, specific brands and types are
	recommended below. Successful completion of the tests requires one peripheral of
	each category of peripherals specified below. Use of other types will cause the
	tests to fail.
	</p>

	<h3 id="usb-audio-interface">USB audio interface</h3>

	<p class="note"><strong>Note:</strong> This list is preliminary and subject to change.</p>

	<ul>
	<li><a href="http://www.presonus.com/products/audiobox-22VSL">Presonus AudioBox
	22VSL</a></li>
	<li><a href="https://www.presonus.com/products/audiobox-usb">Presonus AudioBox
	USB</a></li>
	</ul>

	<table>
	<tr>
	<td width="50%">A USB audio interface (A PreSonus AudioBox 22VSL)
	</td>
	<td width="50%"><img src="/compatibility/cts/images/usb_audio_interface.png" alt="USB audio interface" width="300"
	id="usb_audio_interface" /></td>
	</tr>
	</table>

	<h3 id="usb-headset">USB headset</h3>

	<p class="note"><strong>Note:</strong> This list is preliminary and subject to change.</p>

	<table>
	<tr>
	<td width="50%">A USB headset
	</td>
	<td width="50%"><img src="/compatibility/cts/images/usb_headset.png" alt="USB headset" width="300"
	id="usb_headset" /></td>
	</tr>
	</table>

	<h3 id="peripheral-profiles">Peripheral profiles</h3>

	<p>
	The USB Audio CTS Verifier Tests "know about" these recommended peripherals
	through built-in profiles provided by Android that describe the attributes and
	capabilities of a peripheral. When the peripheral is connected to the Android
	device under test, the correct profile is automatically selected.
	</p>

	<h2 id="required-additional-hardware">Required additional hardware</h2>

	<p>Patch cables (for loopback)
	2 short ¼" male to ¼" male patch cables to
	connect the outputs to the inputs of the USB</p>

	<table>
	<tr>
	<td width="50%">
	¼" male to ¼" male patch cables
	</td>
	<td width="50%"><img src="/compatibility/cts/images/patch_cables.png" alt="patch cables" width="300"
	id="patch_cables" /></td>
	</td>
	</tr>
	</table>

	<p>USB peripheral cable</p>

	<table>
	<tr>
	<td width="50%">This cable (which typically comes with the peripheral), connects the USB
	audio peripheral to the host device
	</td>
	</td>
	<td width="50%"><img src="/compatibility/cts/images/peripheral_cable.png" alt="peripheral cable" width="300"
	id="peripheral_cable" /></td>
	</td>
	</tr>
	</table>

	<p>USB "On The Go" (OTG) adapter</p>

	<table>
	<tr>
	<td width="50%">A USB "On The Go" (OTG) adapter is required to physically connect the
	peripheral to the Android device and indicate to the Android device that it
	should assume the role of "host"
	</td>
	</td>
	<td width="50%"><img src="/compatibility/cts/images/otg_adapter.png" alt="OTG adapter" width="300"
	id="otg_adapter" /></td>
	</td>
	</tr>
	</table>

	<p>Analog headphones to monitor the output of the USB audio interface for the
	Play test.</p>

	<table>
	<tr>
	<td width="50%">Set of analog headphones.
	</td>
	</td>
	<td width="50%"><img src="/compatibility/cts/images/analog_headphones.png" alt="analog headphones" width="300"
	id="analog_headphones" /></td>
	</td>
	</tr>
	</table>

	<h2 id="tests">Tests</h2>

	<p>
	In each test, indicate test success by clicking the <strong>test pass</strong>
	(check mark) button. Otherwise, indicate test failure by clicking the
	<strong>test fail</strong> (exclamation point) button.
	</p>

	<h3 id="attributes-test">Attributes test</h3>

	<h4 id="abstract">Abstract</h4>

	<p>
	This test verifies that the attributes (supported sample-rates, channel
	configurations, sample formats…) match the set of a-priori known attributes of
	the device.
	</p>

	<h4 id="process">Process</h4>

	<p>
	After invoking the test from the main menu, connect a USB audio peripheral. If
	the attributes match, the <strong>test pass</strong> (check mark) button will be
	enabled. Click the <strong>test pass</strong> button to indicate success. If the
	attributes do not match, indicate test failure by clicking the <strong>test
	fail</strong> (exclamation point) button.
	</p>

	<table>
	<tr>
	<td width="50%">Select <em>USB Audio Peripheral Attributes Test</em>.
	</td>
	<td width="50%"><img src="/compatibility/cts/images/attributes_test.png" alt="attributes test" width="300"
	id="attributes test" /></td>
	</tr>
	<tr>
	<td width="50%">Summary of instructions is displayed
	</td>
	<td width="50%"><img src="/compatibility/cts/images/attributes_summary.png" alt="attributes summary" width="300"
	id="attributes_summary" /></td>
	</tr>
	<tr>
	<td width="50%">Pre-connect screen
	</td>
	<td width="50%"><img src="/compatibility/cts/images/attributes_preconnect.png" alt="attributes
	preconnect" width="300"
	id="attributes_preconnect" /></td>
	</tr>
	<tr>
	<td width="50%">USB audio peripheral connected to Android Device with peripheral cable
	and OTG adapter
	</td>
	<td width="50%"><img src="/compatibility/cts/images/attributes_connected.png" alt="attributes connected" width="300"
	id="attributes_connected" /></td>
	</tr>
	<tr>
	<td width="50%">Post-connect screen
	</td>
	<td width="50%"><img src="/compatibility/cts/images/attributes_postconnect.png" alt="attributes post connection" width="300"
	id="attributes_postconnect" /></td>
	</tr>
	</table>

	<h3 id="play-test">Play test</h3>

	<h4 id="abstract">Abstract</h4>

	<p>
	This test verifies that audio playback is functioning. It does this by
	generating a 1KHz test tone and presenting it in stereo (two-channels) to the
	USB audio peripheral.
	</p>

	<h4 id="process">Process</h4>

	<p>
	After invoking the test from the main menu, connect the USB audio interface,
	including the analog headset to the headset output jack on the interface (for
	monitoring).
	</p>

	<p>
	Press the <strong>PLAY</strong> button. If the test tone is heard in both
	channels of the headset, indicate test pass by clicking the <strong>test
	pass</strong> (check mark) button. If either or both of the channels do not play
	the tone, indicate test failure by clicking the <strong>test fail</strong>
	(exclamation point) button.
	</p>

	<h4 id="notes">Notes</h4>

	<table>
	<tr>
	<td width="50%">Select <em>USB Audio Peripheral Play Test</em>
	</td>
	<td width="50%"><img src="/compatibility/cts/images/play_test.png" alt="play test" width="300"
	id="play_test" /></td>
	</tr>
	<tr>
	<td width="50%">Summary of instructions is displayed
	</td>
	<td width="50%"><img src="/compatibility/cts/images/play_summary.png" alt="play summary" width="300"
	id="play_summary" /></td>
	</tr>
	<tr>
	<td width="50%">Pre-connect screen
	</td>
	<td width="50%"><img src="/compatibility/cts/images/play_preconnect.png" alt="play preconnect" width="300"
	id="play_preconnect" /></td>
	</tr>
	<tr>
	<td width="50%">Connect the USB audio peripheral to the Android Device
	<p>
	The headphones are connected to the headphone output jack on the USB audio
	interface for monitoring
	</td>
	<td width="50%"><img src="/compatibility/cts/images/play_connected.png" alt="play connected" width="300"
	id="play_connected" /></td>
	</tr>
	<tr>
	<td width="50%">Post-connect screen
	</td>
	<td width="50%"><img src="/compatibility/cts/images/play_postconnect.png" alt="play post connection" width="300"
	id="play_postconnect" /></td>
	</tr>
	</table>


	<h3 id="record-loopback-test">Record (loopback) test</h3>

	<h4 id="abstract">Abstract</h4>

	<p>
	This test verifies that audio recording is functioning. It does this by
	generating a tone at the outputs of the USB audio interface, which is then
	routed via patch cords to the inputs of the USB audio peripheral.
	</p>

	<h4 id="process">Process</h4>

	<p>
	After invoking the test from the main menu, connect the USB audio interface.
	Connect the analog outputs to the analog inputs with patch cables. Press the
	<strong>RECORD LOOPBACK</strong> button. If both the channels of the recorded
	test tone are shown in the view below, indicate test pass by clicking the
	<strong>test pass</strong> (check mark) button. If either or both of the
	channels does not display, indicate test failure by clicking the <strong>test
	fail</strong> (exclamation point) button.
	</p>

	<h4 id="notes">Notes</h4>

	<p>
	Ensure positive connection of both input and output jacks on the peripheral. It
	will be necessary to adjust the input levels to correctly display the recorded
	signal.
	</p>

	<table>
	<tr>
	<td width="50%">Select <em>USB Audio Peripheral Record Test</em>
	</td>
	<td width="50%"><img src="/compatibility/cts/images/record_test.png" alt="record test" width="300"
	id="record_test" /></td>
	</tr>
	<tr>
	<td width="50%">Summary of instructions is displayed
	</td>
	<td width="50%"><img src="/compatibility/cts/images/record_summary.png" alt="record summary" width="300"
	id="record_summary" /></td>
	</tr>
	<tr>
	<td width="50%">Pre-connect screen
	</td>
	<td width="50%"><img src="/compatibility/cts/images/record_preconnect.png" alt="record preconnect" width="300"
	id="record_preconnect" /></td>
	</tr>
	<tr>
	<td width="50%">USB audio Interface with loopback connected to Android device
	</td>
	<td width="50%"><img src="/compatibility/cts/images/record_connected.png" alt="record connected" width="300"
	id="record_connected" /></td>
	</tr>
	<tr>
	<td width="50%">Connections on the back of the USB audio interface
	</td>
	<td width="50%"><img src="/compatibility/cts/images/record_connected_back.png" alt="record connected in back" width="300"
	id="record_connected_back" /></td>
	</tr>
	<tr>
	<td width="50%">Connections on the front of the USB audio interface
	</td>
	<td width="50%"><img src="/compatibility/cts/images/record_connected_front.png" alt="record connected in front" width="300"
	id="record_connected_front" /></td>
	</tr>
	<tr>
	<td width="50%">Post-connect screen, with record test running
	</td>
	<td width="50%"><img src="/compatibility/cts/images/record_postconnect.png" alt="record post connection" width="300"
	id="record_postconnect" /></td>
	</tr>
	</table>
	<h3></h3>
	<h3 id="headset-buttons-test">Headset buttons test</h3>
	<h4 id="abstract">Abstract</h4>
	<p>
	This test verifies the <strong>media/transport </strong>buttons on the
	recommended headset are correctly recognized.
	</p>
	<h4 id="process">Process</h4>
	<p>
	After invoking the test from the main menu, connect the USB headset peripheral.
	Press each <strong>media/transport</strong> (play, pause, volume up & volume
	down) button on the headset. As each is recognized, it will be recognized in the
	test panel. When all buttons have been recognized, the <strong>test
	pass</strong> (check mark) button will be enabled. Click the <strong>test
	pass</strong> button to indicate success. If the full set of buttons is not
	recognized, indicate test failure by clicking the <strong>test fail</strong>
	(exclamation point) button.
	</p>
	<h4 id="notes">Notes</h4>
	<table>
	<tr>
	<td width="50%">The USB headset peripheral connected to the Android device
	<p>
	Note the OTG adapter
	</td>
	<td width="50%"><img src="/compatibility/cts/images/buttons_connected.png" alt="buttons connected" width="300"
	id="buttons_connected" /></td>
	</tr>
	<tr>
	<td width="50%">Select <em>USB Audio Peripheral Buttons Test</em>
	</td>
	<td width="50%"><img src="/compatibility/cts/images/buttons_test.png" alt="buttons test" width="300"
	id="buttons_test" /></td>
	</tr>
	<tr>
	<td width="50%">Summary of instructions is displayed
	</td>
	<td width="50%"><img src="/compatibility/cts/images/buttons_summary.png" alt="buttons summary" width="300"
	id="buttons_summary" /></td>
	</tr>
	<tr>
	<td width="50%">Peripheral connected, but no buttons recognized (yet)
	<p>
	Note that the expected (buttons which are known to the device profile) are
	indicated with with white text; those that are not part of the test peripheral
	are displayed in grey text
	</td>
	<td width="50%"><img src="/compatibility/cts/images/buttons_not_recognized.png" alt="buttons not recognized" width="300"
	id="buttons not recognized" /></td>
	</tr>
	<tr>
	<td width="50%">Peripheral connected, and expected buttons recognized
	</td>
	<td width="50%"><img src="/compatibility/cts/images/buttons_recognized.png" alt="buttons recognized" width="300"
	id="buttons recognized" /></td>
	</tr>
	</table>

	</body>
	</html>