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Diffstat (limited to 'Demos/Device/ClassDriver/AudioOutput/AudioOutput.c')
| -rw-r--r-- | Demos/Device/ClassDriver/AudioOutput/AudioOutput.c | 311 |
1 files changed, 311 insertions, 0 deletions
diff --git a/Demos/Device/ClassDriver/AudioOutput/AudioOutput.c b/Demos/Device/ClassDriver/AudioOutput/AudioOutput.c new file mode 100644 index 0000000000..4c78deb9f6 --- /dev/null +++ b/Demos/Device/ClassDriver/AudioOutput/AudioOutput.c @@ -0,0 +1,311 @@ +/* + LUFA Library + Copyright (C) Dean Camera, 2017. + + dean [at] fourwalledcubicle [dot] com + www.lufa-lib.org +*/ + +/* + Copyright 2017 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 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 + 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 = + { + .ControlInterfaceNumber = INTERFACE_ID_AudioControl, + .StreamingInterfaceNumber = INTERFACE_ID_AudioStream, + .DataOUTEndpoint = + { + .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. + */ +int main(void) +{ + SetupHardware(); + + LEDs_SetAllLEDs(LEDMASK_USB_NOTREADY); + GlobalInterruptEnable(); + + for (;;) + { + Audio_Device_USBTask(&Speaker_Audio_Interface); + USB_USBTask(); + } +} + +/** Configures the board hardware and chip peripherals for the demo's functionality. */ +void SetupHardware(void) +{ +#if (ARCH == ARCH_AVR8) + /* Disable watchdog if enabled by bootloader/fuses */ + MCUSR &= ~(1 << WDRF); + wdt_disable(); + + /* Disable clock division */ + clock_prescale_set(clock_div_1); +#endif + + /* 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 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 == Speaker_Audio_Interface.Config.DataOUTEndpoint.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; +} |