/*
LUFA Library
- Copyright (C) Dean Camera, 2010.
+ Copyright (C) Dean Camera, 2012.
dean [at] fourwalledcubicle [dot] com
- www.fourwalledcubicle.com
+ www.lufa-lib.org
*/
/*
- Copyright 2010 Dean Camera (dean [at] fourwalledcubicle [dot] com)
+ Copyright 2012 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
},
};
+/** 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.
*/
for (;;)
{
- ProcessNextSample();
-
Audio_Device_USBTask(&Microphone_Audio_Interface);
USB_USBTask();
}
ADC_StartReading(ADC_REFERENCE_AVCC | ADC_RIGHT_ADJUSTED | MIC_IN_ADC_MUX_MASK);
}
-/** Processes the next audio sample by reading the last ADC conversion and writing it to the audio
- * interface, each time the sample reload timer period elapses to give a constant sample rate.
- */
-void ProcessNextSample(void)
+/** ISR to handle the reloading of the data endpoint with the next sample. */
+ISR(TIMER0_COMPA_vect, ISR_BLOCK)
{
- /* Check if the sample reload timer period has elapsed, and that the USB bus is ready for a new sample */
- if ((TIFR0 & (1 << OCF0A)) && Audio_Device_IsReadyForNextSample(&Microphone_Audio_Interface))
+ uint8_t PrevEndpoint = Endpoint_GetCurrentEndpoint();
+
+ /* Check that the USB bus is ready for the next sample to write */
+ if (Audio_Device_IsReadyForNextSample(&Microphone_Audio_Interface))
{
- /* Clear the sample reload timer compare flag, ready for the next interval */
- TIFR0 |= (1 << OCF0A);
-
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);
}
+
+ Endpoint_SelectEndpoint(PrevEndpoint);
}
/** Event handler for the library USB Connection event. */
LEDs_SetAllLEDs(LEDMASK_USB_ENUMERATING);
/* Sample reload timer initialization */
- OCR0A = (F_CPU / 8 / AUDIO_SAMPLE_FREQUENCY) - 1;
+ TIMSK0 = (1 << OCIE0A);
+ OCR0A = ((F_CPU / 8 / CurrentAudioSampleFrequency) - 1);
TCCR0A = (1 << WGM01); // CTC mode
TCCR0B = (1 << CS01); // Fcpu/8 speed
}
LEDs_SetAllLEDs(ConfigSuccess ? LEDMASK_USB_READY : LEDMASK_USB_ERROR);
}
-/** Event handler for the library USB Unhandled Control Request event. */
-void EVENT_USB_Device_UnhandledControlRequest(void)
+/** Event handler for the library USB Control Request reception event. */
+void EVENT_USB_Device_ControlRequest(void)
{
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 retreived 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 == (ENDPOINT_DIR_IN | Microphone_Audio_Interface.Config.DataINEndpointNumber))
+ {
+ /* 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 retreived 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 \ref 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;
+}
projects / pub / USBasp.git / blobdiff