/*
LUFA Library
- Copyright (C) Dean Camera, 2011.
+ Copyright (C) Dean Camera, 2013.
dean [at] fourwalledcubicle [dot] com
www.lufa-lib.org
*/
/*
- Copyright 2011 Dean Camera (dean [at] fourwalledcubicle [dot] com)
+ Copyright 2013 Dean Camera (dean [at] fourwalledcubicle [dot] com)
Permission to use, copy, modify, distribute, and sell this
software and its documentation for any purpose is hereby granted
advertising or publicity pertaining to distribution of the
software without specific, written prior permission.
- The author disclaim all warranties with regard to this
+ The author disclaims all warranties with regard to this
software, including all implied warranties of merchantability
and fitness. In no event shall the author be liable for any
special, indirect or consequential damages or any damages
{
.Config =
{
+ .ControlInterfaceNumber = 0,
.StreamingInterfaceNumber = 1,
-
- .DataINEndpointNumber = AUDIO_STREAM_EPNUM,
- .DataINEndpointSize = AUDIO_STREAM_EPSIZE,
+ .DataINEndpoint =
+ {
+ .Address = AUDIO_STREAM_EPADDR,
+ .Size = AUDIO_STREAM_EPSIZE,
+ .Banks = 2,
+ },
},
};
+/** Current audio sampling frequency of the streaming audio endpoint. */
+static uint32_t CurrentAudioSampleFrequency = 48000;
+
/** Main program entry point. This routine contains the overall program flow, including initial
* setup of all components and the main program loop.
SetupHardware();
LEDs_SetAllLEDs(LEDMASK_USB_NOTREADY);
- sei();
+ GlobalInterruptEnable();
for (;;)
{
USB_Init();
/* Start the ADC conversion in free running mode */
- ADC_StartReading(ADC_REFERENCE_AVCC | ADC_RIGHT_ADJUSTED | MIC_IN_ADC_MUX_MASK);
+ ADC_StartReading(ADC_REFERENCE_AVCC | ADC_RIGHT_ADJUSTED | ADC_GET_CHANNEL_MASK(MIC_IN_ADC_CHANNEL));
}
/** ISR to handle the reloading of the data endpoint with the next sample. */
{
uint8_t PrevEndpoint = Endpoint_GetCurrentEndpoint();
- /* Check if the sample reload timer period has elapsed, and that the USB bus is ready for a new sample */
+ /* Check that the USB bus is ready for the next sample to write */
if (Audio_Device_IsReadyForNextSample(&Microphone_Audio_Interface))
{
int16_t AudioSample;
#if defined(USE_TEST_TONE)
static uint8_t SquareWaveSampleCount;
static int16_t CurrentWaveValue;
-
+
/* In test tone mode, generate a square wave at 1/256 of the sample rate */
if (SquareWaveSampleCount++ == 0xFF)
CurrentWaveValue ^= 0x8000;
-
+
/* Only generate audio if the board button is being pressed */
AudioSample = (Buttons_GetStatus() & BUTTONS_BUTTON1) ? CurrentWaveValue : 0;
#else
AudioSample -= (SAMPLE_MAX_RANGE / 2);
#endif
#endif
-
+
Audio_Device_WriteSample16(&Microphone_Audio_Interface, AudioSample);
}
/* Sample reload timer initialization */
TIMSK0 = (1 << OCIE0A);
- OCR0A = ((F_CPU / 8 / AUDIO_SAMPLE_FREQUENCY) - 1);
+ OCR0A = ((F_CPU / 8 / CurrentAudioSampleFrequency) - 1);
TCCR0A = (1 << WGM01); // CTC mode
TCCR0B = (1 << CS01); // Fcpu/8 speed
}
Audio_Device_ProcessControlRequest(&Microphone_Audio_Interface);
}
+/** Audio class driver callback for the setting and retrieval of streaming endpoint properties. This callback must be implemented
+ * in the user application to handle property manipulations on streaming audio endpoints.
+ *
+ * When the DataLength parameter is NULL, this callback should only indicate whether the specified operation is valid for
+ * the given endpoint index, and should return as fast as possible. When non-NULL, this value may be altered for GET operations
+ * to indicate the size of the retrieved data.
+ *
+ * \note The length of the retrieved data stored into the Data buffer on GET operations should not exceed the initial value
+ * of the \c DataLength parameter.
+ *
+ * \param[in,out] AudioInterfaceInfo Pointer to a structure containing an Audio Class configuration and state.
+ * \param[in] EndpointProperty Property of the endpoint to get or set, a value from Audio_ClassRequests_t.
+ * \param[in] EndpointAddress Address of the streaming endpoint whose property is being referenced.
+ * \param[in] EndpointControl Parameter of the endpoint to get or set, a value from Audio_EndpointControls_t.
+ * \param[in,out] DataLength For SET operations, the length of the parameter data to set. For GET operations, the maximum
+ * length of the retrieved data. When NULL, the function should return whether the given property
+ * and parameter is valid for the requested endpoint without reading or modifying the Data buffer.
+ * \param[in,out] Data Pointer to a location where the parameter data is stored for SET operations, or where
+ * the retrieved data is to be stored for GET operations.
+ *
+ * \return Boolean \c true if the property get/set was successful, \c false otherwise
+ */
+bool CALLBACK_Audio_Device_GetSetEndpointProperty(USB_ClassInfo_Audio_Device_t* const AudioInterfaceInfo,
+ const uint8_t EndpointProperty,
+ const uint8_t EndpointAddress,
+ const uint8_t EndpointControl,
+ uint16_t* const DataLength,
+ uint8_t* Data)
+{
+ /* Check the requested endpoint to see if a supported endpoint is being manipulated */
+ if (EndpointAddress == Microphone_Audio_Interface.Config.DataINEndpoint.Address)
+ {
+ /* Check the requested control to see if a supported control is being manipulated */
+ if (EndpointControl == AUDIO_EPCONTROL_SamplingFreq)
+ {
+ switch (EndpointProperty)
+ {
+ case AUDIO_REQ_SetCurrent:
+ /* Check if we are just testing for a valid property, or actually adjusting it */
+ if (DataLength != NULL)
+ {
+ /* Set the new sampling frequency to the value given by the host */
+ CurrentAudioSampleFrequency = (((uint32_t)Data[2] << 16) | ((uint32_t)Data[1] << 8) | (uint32_t)Data[0]);
+
+ /* Adjust sample reload timer to the new frequency */
+ OCR0A = ((F_CPU / 8 / CurrentAudioSampleFrequency) - 1);
+ }
+
+ return true;
+ case AUDIO_REQ_GetCurrent:
+ /* Check if we are just testing for a valid property, or actually reading it */
+ if (DataLength != NULL)
+ {
+ *DataLength = 3;
+
+ Data[2] = (CurrentAudioSampleFrequency >> 16);
+ Data[1] = (CurrentAudioSampleFrequency >> 8);
+ Data[0] = (CurrentAudioSampleFrequency & 0xFF);
+ }
+
+ return true;
+ }
+ }
+ }
+
+ return false;
+}
+
+/** Audio class driver callback for the setting and retrieval of streaming interface properties. This callback must be implemented
+ * in the user application to handle property manipulations on streaming audio interfaces.
+ *
+ * When the DataLength parameter is NULL, this callback should only indicate whether the specified operation is valid for
+ * the given entity and should return as fast as possible. When non-NULL, this value may be altered for GET operations
+ * to indicate the size of the retrieved data.
+ *
+ * \note The length of the retrieved data stored into the Data buffer on GET operations should not exceed the initial value
+ * of the \c DataLength parameter.
+ *
+ * \param[in,out] AudioInterfaceInfo Pointer to a structure containing an Audio Class configuration and state.
+ * \param[in] Property Property of the interface to get or set, a value from Audio_ClassRequests_t.
+ * \param[in] EntityAddress Address of the audio entity whose property is being referenced.
+ * \param[in] Parameter Parameter of the entity to get or set, specific to each type of entity (see USB Audio specification).
+ * \param[in,out] DataLength For SET operations, the length of the parameter data to set. For GET operations, the maximum
+ * length of the retrieved data. When NULL, the function should return whether the given property
+ * and parameter is valid for the requested endpoint without reading or modifying the Data buffer.
+ * \param[in,out] Data Pointer to a location where the parameter data is stored for SET operations, or where
+ * the retrieved data is to be stored for GET operations.
+ *
+ * \return Boolean \c true if the property GET/SET was successful, \c false otherwise
+ */
+bool CALLBACK_Audio_Device_GetSetInterfaceProperty(USB_ClassInfo_Audio_Device_t* const AudioInterfaceInfo,
+ const uint8_t Property,
+ const uint8_t EntityAddress,
+ const uint16_t Parameter,
+ uint16_t* const DataLength,
+ uint8_t* Data)
+{
+ /* No audio interface entities in the device descriptor, thus no properties to get or set. */
+ return false;
+}