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/** \file
*
* This file contains special DoxyGen information for the generation of the main page and other special
* documentation pages. It is not a project source file.
*/
/** \mainpage Audio Output Device Demo
*
* \section SSec_Info USB Information:
*
* The following table gives a rundown of the USB utilization of this demo.
*
* <table>
* <tr>
* <td><b>USB Mode:</b></td>
* <td>Device</td>
* </tr>
* <tr>
* <td><b>USB Class:</b></td>
* <td>Audio Class</td>
* </tr>
* <tr>
* <td><b>USB Subclass:</b></td>
* <td>Standard Audio Device</td>
* </tr>
* <tr>
* <td><b>Relevant Standards:</b></td>
* <td>USBIF Audio Class Specification</td>
* <td>USBIF Audio Class Terminal Types Specification</td>
* <td>USBIF Audio Data Formats Specification</td>
* </tr>
* <tr>
* <td><b>Usable Speeds:</b></td>
* <td>Full Speed Mode</td>
* </tr>
* </table>
*
* \section SSec_Description Project Description:
*
* Audio demonstration application. This gives a simple reference
* application for implementing a USB Audio Output device using the
* basic USB Audio drivers in all modern OSes (i.e. no special drivers
* required).
*
* On start-up the system will automatically enumerate and function
* as a USB speaker. Incoming audio will output in 8-bit PWM onto
* the timer output (timer 3 for the AT90USBXXX6/7 USB AVRs, timer 1 for
* the AT90USBXXX2 controller AVRs) compare channel A for AUDIO_OUT_MONO
* mode, on channels A and B for AUDIO_OUT_STEREO and on the board LEDs
* for AUDIO_OUT_LEDS mode. Decouple audio outputs with a capacitor and
* attach to a speaker to hear the audio.
*
* Under Windows, if a driver request dialogue pops up, select the option
* to automatically install the appropriate drivers.
*
* \section SSec_Options Project Options
*
* The following defines can be found in this demo, which can control the demo behaviour when defined, or changed in value.
*
* <table>
* <tr>
* <td><b>Define Name:</b></td>
* <td><b>Location:</b></td>
* <td><b>Description:</b></td>
* </tr>
* <tr>
* <td>AUDIO_OUT_STEREO</td>
* <td>Makefile CDEFS</td>
* <td>When defined, this outputs the audio samples in stereo to the timer output pins of the microcontroller.</td>
* </tr>
* <tr>
* <td>AUDIO_OUT_MONO</td>
* <td>Makefile CDEFS</td>
* <td>When defined, this outputs the audio samples in mono to the timer output pin of the microcontroller.</td>
* </tr>
* <tr>
* <td>AUDIO_OUT_LEDS</td>
* <td>Makefile CDEFS</td>
* <td>When defined, this outputs the audio samples in stereo to the board LEDs.</td>
* </tr>
* <tr>
* <td>AUDIO_OUT_PORTC</td>
* <td>Makefile CDEFS</td>
* <td>When defined, this outputs the audio samples in mono to port C of the microcontroller, for connection to an
* external DAC.</td>
* </tr>
* <tr>
* <td>AUDIO_SAMPLE_FREQUENCY</td>
* <td>Descriptors.h</td>
* <td>Gives the audio sample rate per channel for the audio stream, in Hz.</td>
* </tr>
* </table>
*/
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