You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
275 lines
9.8 KiB
275 lines
9.8 KiB
/*
|
|
LUFA Library
|
|
Copyright (C) Dean Camera, 2011.
|
|
|
|
dean [at] fourwalledcubicle [dot] com
|
|
www.lufa-lib.org
|
|
*/
|
|
|
|
/*
|
|
Copyright 2011 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
|
|
without fee, provided that the above copyright notice appear in
|
|
all copies and that both that the copyright notice and this
|
|
permission notice and warranty disclaimer appear in supporting
|
|
documentation, and that the name of the author not be used in
|
|
advertising or publicity pertaining to distribution of the
|
|
software without specific, written prior permission.
|
|
|
|
The author disclaim 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
|
|
whatsoever resulting from loss of use, data or profits, whether
|
|
in an action of contract, negligence or other tortious action,
|
|
arising out of or in connection with the use or performance of
|
|
this software.
|
|
*/
|
|
|
|
/** \file
|
|
*
|
|
* Main source file for the AudioOutput demo. This file contains the main tasks of
|
|
* the demo and is responsible for the initial application hardware configuration.
|
|
*/
|
|
|
|
#include "AudioOutput.h"
|
|
|
|
/** LUFA Audio Class driver interface configuration and state information. This structure is
|
|
* passed to all Audio Class driver functions, so that multiple instances of the same class
|
|
* within a device can be differentiated from one another.
|
|
*/
|
|
USB_ClassInfo_Audio_Device_t Speaker_Audio_Interface =
|
|
{
|
|
.Config =
|
|
{
|
|
.StreamingInterfaceNumber = 1,
|
|
|
|
.DataOUTEndpointNumber = AUDIO_STREAM_EPNUM,
|
|
.DataOUTEndpointSize = AUDIO_STREAM_EPSIZE,
|
|
},
|
|
};
|
|
|
|
/** 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.
|
|
*/
|
|
int main(void)
|
|
{
|
|
SetupHardware();
|
|
|
|
LEDs_SetAllLEDs(LEDMASK_USB_NOTREADY);
|
|
sei();
|
|
|
|
for (;;)
|
|
{
|
|
Audio_Device_USBTask(&Speaker_Audio_Interface);
|
|
USB_USBTask();
|
|
}
|
|
}
|
|
|
|
/** Configures the board hardware and chip peripherals for the demo's functionality. */
|
|
void SetupHardware(void)
|
|
{
|
|
/* Disable watchdog if enabled by bootloader/fuses */
|
|
MCUSR &= ~(1 << WDRF);
|
|
wdt_disable();
|
|
|
|
/* Disable clock division */
|
|
clock_prescale_set(clock_div_1);
|
|
|
|
/* Hardware Initialization */
|
|
LEDs_Init();
|
|
USB_Init();
|
|
}
|
|
|
|
/** ISR to handle the reloading of the PWM timer with the next sample. */
|
|
ISR(TIMER0_COMPA_vect, ISR_BLOCK)
|
|
{
|
|
uint8_t PrevEndpoint = Endpoint_GetCurrentEndpoint();
|
|
|
|
/* Check that the USB bus is ready for the next sample to read */
|
|
if (Audio_Device_IsSampleReceived(&Speaker_Audio_Interface))
|
|
{
|
|
/* Retrieve the signed 16-bit left and right audio samples, convert to 8-bit */
|
|
int8_t LeftSample_8Bit = (Audio_Device_ReadSample16(&Speaker_Audio_Interface) >> 8);
|
|
int8_t RightSample_8Bit = (Audio_Device_ReadSample16(&Speaker_Audio_Interface) >> 8);
|
|
|
|
/* Mix the two channels together to produce a mono, 8-bit sample */
|
|
int8_t MixedSample_8Bit = (((int16_t)LeftSample_8Bit + (int16_t)RightSample_8Bit) >> 1);
|
|
|
|
#if defined(AUDIO_OUT_MONO)
|
|
/* Load the sample into the PWM timer channel */
|
|
OCR3A = (MixedSample_8Bit ^ (1 << 7));
|
|
#elif defined(AUDIO_OUT_STEREO)
|
|
/* Load the dual 8-bit samples into the PWM timer channels */
|
|
OCR3A = (LeftSample_8Bit ^ (1 << 7));
|
|
OCR3B = (RightSample_8Bit ^ (1 << 7));
|
|
#elif defined(AUDIO_OUT_PORTC)
|
|
/* Load the 8-bit mixed sample into PORTC */
|
|
PORTC = MixedSample_8Bit;
|
|
#endif
|
|
|
|
uint8_t LEDMask = LEDS_NO_LEDS;
|
|
|
|
/* Turn on LEDs as the sample amplitude increases */
|
|
if (MixedSample_8Bit > 16)
|
|
LEDMask = (LEDS_LED1 | LEDS_LED2 | LEDS_LED3 | LEDS_LED4);
|
|
else if (MixedSample_8Bit > 8)
|
|
LEDMask = (LEDS_LED1 | LEDS_LED2 | LEDS_LED3);
|
|
else if (MixedSample_8Bit > 4)
|
|
LEDMask = (LEDS_LED1 | LEDS_LED2);
|
|
else if (MixedSample_8Bit > 2)
|
|
LEDMask = (LEDS_LED1);
|
|
|
|
LEDs_SetAllLEDs(LEDMask);
|
|
}
|
|
|
|
Endpoint_SelectEndpoint(PrevEndpoint);
|
|
}
|
|
|
|
/** Event handler for the library USB Connection event. */
|
|
void EVENT_USB_Device_Connect(void)
|
|
{
|
|
LEDs_SetAllLEDs(LEDMASK_USB_ENUMERATING);
|
|
|
|
/* Sample reload timer initialization */
|
|
TIMSK0 = (1 << OCIE0A);
|
|
OCR0A = ((F_CPU / 8 / CurrentAudioSampleFrequency) - 1);
|
|
TCCR0A = (1 << WGM01); // CTC mode
|
|
TCCR0B = (1 << CS01); // Fcpu/8 speed
|
|
|
|
#if defined(AUDIO_OUT_MONO)
|
|
/* Set speaker as output */
|
|
DDRC |= (1 << 6);
|
|
#elif defined(AUDIO_OUT_STEREO)
|
|
/* Set speakers as outputs */
|
|
DDRC |= ((1 << 6) | (1 << 5));
|
|
#elif defined(AUDIO_OUT_PORTC)
|
|
/* Set PORTC as outputs */
|
|
DDRC |= 0xFF;
|
|
#endif
|
|
|
|
#if (defined(AUDIO_OUT_MONO) || defined(AUDIO_OUT_STEREO))
|
|
/* PWM speaker timer initialization */
|
|
TCCR3A = ((1 << WGM30) | (1 << COM3A1) | (1 << COM3A0)
|
|
| (1 << COM3B1) | (1 << COM3B0)); // Set on match, clear on TOP
|
|
TCCR3B = ((1 << WGM32) | (1 << CS30)); // Fast 8-Bit PWM, F_CPU speed
|
|
#endif
|
|
}
|
|
|
|
/** Event handler for the library USB Disconnection event. */
|
|
void EVENT_USB_Device_Disconnect(void)
|
|
{
|
|
LEDs_SetAllLEDs(LEDMASK_USB_NOTREADY);
|
|
|
|
/* Stop the sample reload timer */
|
|
TCCR0B = 0;
|
|
|
|
#if (defined(AUDIO_OUT_MONO) || defined(AUDIO_OUT_STEREO))
|
|
/* Stop the PWM generation timer */
|
|
TCCR3B = 0;
|
|
#endif
|
|
|
|
#if defined(AUDIO_OUT_MONO)
|
|
/* Set speaker as input to reduce current draw */
|
|
DDRC &= ~(1 << 6);
|
|
#elif defined(AUDIO_OUT_STEREO)
|
|
/* Set speakers as inputs to reduce current draw */
|
|
DDRC &= ~((1 << 6) | (1 << 5));
|
|
#elif defined(AUDIO_OUT_PORTC)
|
|
/* Set PORTC low */
|
|
PORTC = 0x00;
|
|
#endif
|
|
}
|
|
|
|
/** Event handler for the library USB Configuration Changed event. */
|
|
void EVENT_USB_Device_ConfigurationChanged(void)
|
|
{
|
|
bool ConfigSuccess = true;
|
|
|
|
ConfigSuccess &= Audio_Device_ConfigureEndpoints(&Speaker_Audio_Interface);
|
|
|
|
LEDs_SetAllLEDs(ConfigSuccess ? LEDMASK_USB_READY : LEDMASK_USB_ERROR);
|
|
}
|
|
|
|
/** Event handler for the library USB Control Request reception event. */
|
|
void EVENT_USB_Device_ControlRequest(void)
|
|
{
|
|
Audio_Device_ProcessControlRequest(&Speaker_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 true if the property get/set was successful, 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_DESCRIPTOR_DIR_OUT | Speaker_Audio_Interface.Config.DataOUTEndpointNumber))
|
|
{
|
|
/* Check the requested control to see if a supported control is being manipulated */
|
|
if (EndpointControl == AUDIO_EPCONTROL_SamplingFreq)
|
|
{
|
|
/* Check the requested property to see if a supported property is being manipulated */
|
|
if (EndpointProperty == 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;
|
|
}
|
|
else if (EndpointProperty == 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;
|
|
}
|