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Diffstat (limited to 'lib/lufa/Demos/Device/LowLevel/AudioOutput/AudioOutput.c')
| -rw-r--r-- | lib/lufa/Demos/Device/LowLevel/AudioOutput/AudioOutput.c | 293 |
1 files changed, 0 insertions, 293 deletions
diff --git a/lib/lufa/Demos/Device/LowLevel/AudioOutput/AudioOutput.c b/lib/lufa/Demos/Device/LowLevel/AudioOutput/AudioOutput.c deleted file mode 100644 index 7966ba6ea2..0000000000 --- a/lib/lufa/Demos/Device/LowLevel/AudioOutput/AudioOutput.c +++ /dev/null @@ -1,293 +0,0 @@ -/* - 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" - -/** Flag to indicate if the streaming audio alternative interface has been selected by the host. */ -static bool StreamingAudioInterfaceSelected = false; - -/** 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 (;;) - { - 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(); -} - -/** Event handler for the USB_Connect event. This indicates that the device is enumerating via the status LEDs, and - * configures the sample update and PWM timers. - */ -void EVENT_USB_Device_Connect(void) -{ - /* Indicate USB enumerating */ - 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 USB_Disconnect event. This indicates that the device is no longer connected to a host via - * the status LEDs, disables the sample update and PWM output timers and stops the USB and Audio management tasks. - */ -void EVENT_USB_Device_Disconnect(void) -{ - /* Stop the timers */ - TCCR0B = 0; - #if (defined(AUDIO_OUT_MONO) || defined(AUDIO_OUT_STEREO)) - 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 - - /* Indicate streaming audio interface not selected */ - StreamingAudioInterfaceSelected = false; - - /* Indicate USB not ready */ - LEDs_SetAllLEDs(LEDMASK_USB_NOTREADY); -} - -/** Event handler for the USB_ConfigurationChanged event. This is fired when the host set the current configuration - * of the USB device after enumeration - the device endpoints are configured. - */ -void EVENT_USB_Device_ConfigurationChanged(void) -{ - bool ConfigSuccess = true; - - /* Setup Audio Stream Endpoint */ - ConfigSuccess &= Endpoint_ConfigureEndpoint(AUDIO_STREAM_EPADDR, EP_TYPE_ISOCHRONOUS, AUDIO_STREAM_EPSIZE, 2); - - /* Indicate endpoint configuration success or failure */ - LEDs_SetAllLEDs(ConfigSuccess ? LEDMASK_USB_READY : LEDMASK_USB_ERROR); -} - -/** Event handler for the USB_ControlRequest event. This is used to catch and process control requests sent to - * the device from the USB host before passing along unhandled control requests to the library for processing - * internally. - */ -void EVENT_USB_Device_ControlRequest(void) -{ - /* Process General and Audio specific control requests */ - switch (USB_ControlRequest.bRequest) - { - case REQ_SetInterface: - /* Set Interface is not handled by the library, as its function is application-specific */ - if (USB_ControlRequest.bmRequestType == (REQDIR_HOSTTODEVICE | REQTYPE_STANDARD | REQREC_INTERFACE)) - { - Endpoint_ClearSETUP(); - Endpoint_ClearStatusStage(); - - /* Check if the host is enabling the audio interface (setting AlternateSetting to 1) */ - StreamingAudioInterfaceSelected = ((USB_ControlRequest.wValue) != 0); - } - - break; - case AUDIO_REQ_GetStatus: - /* Get Status request can be directed at either the interface or endpoint, neither is currently used - * according to the latest USB Audio 1.0 standard, but must be ACKed with no data when requested */ - if ((USB_ControlRequest.bmRequestType == (REQDIR_HOSTTODEVICE | REQTYPE_CLASS | REQREC_INTERFACE)) || - (USB_ControlRequest.bmRequestType == (REQDIR_HOSTTODEVICE | REQTYPE_CLASS | REQREC_ENDPOINT))) - { - Endpoint_ClearSETUP(); - Endpoint_ClearStatusStage(); - } - - break; - case AUDIO_REQ_SetCurrent: - if (USB_ControlRequest.bmRequestType == (REQDIR_HOSTTODEVICE | REQTYPE_CLASS | REQREC_ENDPOINT)) - { - /* Extract out the relevant request information to get the target Endpoint address and control being set */ - uint8_t EndpointAddress = (uint8_t)USB_ControlRequest.wIndex; - uint8_t EndpointControl = (USB_ControlRequest.wValue >> 8); - - /* Only handle SET CURRENT requests to the audio endpoint's sample frequency property */ - if ((EndpointAddress == AUDIO_STREAM_EPADDR) && (EndpointControl == AUDIO_EPCONTROL_SamplingFreq)) - { - uint8_t SampleRate[3]; - - Endpoint_ClearSETUP(); - Endpoint_Read_Control_Stream_LE(SampleRate, sizeof(SampleRate)); - Endpoint_ClearIN(); - - /* Set the new sampling frequency to the value given by the host */ - CurrentAudioSampleFrequency = (((uint32_t)SampleRate[2] << 16) | ((uint32_t)SampleRate[1] << 8) | (uint32_t)SampleRate[0]); - - /* Adjust sample reload timer to the new frequency */ - OCR0A = ((F_CPU / 8 / CurrentAudioSampleFrequency) - 1); - } - } - - break; - case AUDIO_REQ_GetCurrent: - if (USB_ControlRequest.bmRequestType == (REQDIR_DEVICETOHOST | REQTYPE_CLASS | REQREC_ENDPOINT)) - { - /* Extract out the relevant request information to get the target Endpoint address and control being retrieved */ - uint8_t EndpointAddress = (uint8_t)USB_ControlRequest.wIndex; - uint8_t EndpointControl = (USB_ControlRequest.wValue >> 8); - - /* Only handle GET CURRENT requests to the audio endpoint's sample frequency property */ - if ((EndpointAddress == AUDIO_STREAM_EPADDR) && (EndpointControl == AUDIO_EPCONTROL_SamplingFreq)) - { - uint8_t SampleRate[3]; - - /* Convert the sampling rate value into the 24-bit format the host expects for the property */ - SampleRate[2] = (CurrentAudioSampleFrequency >> 16); - SampleRate[1] = (CurrentAudioSampleFrequency >> 8); - SampleRate[0] = (CurrentAudioSampleFrequency & 0xFF); - - Endpoint_ClearSETUP(); - Endpoint_Write_Control_Stream_LE(SampleRate, sizeof(SampleRate)); - Endpoint_ClearOUT(); - } - } - - break; - } -} - -/** ISR to handle the reloading of the PWM timer with the next sample. */ -ISR(TIMER0_COMPA_vect, ISR_BLOCK) -{ - uint8_t PrevEndpoint = Endpoint_GetCurrentEndpoint(); - - /* Select the audio stream endpoint */ - Endpoint_SelectEndpoint(AUDIO_STREAM_EPADDR); - - /* Check if the current endpoint can be read from (contains a packet) and the host is sending data */ - if (Endpoint_IsOUTReceived() && StreamingAudioInterfaceSelected) - { - /* Retrieve the signed 16-bit left and right audio samples, convert to 8-bit */ - int8_t LeftSample_8Bit = ((int16_t)Endpoint_Read_16_LE() >> 8); - int8_t RightSample_8Bit = ((int16_t)Endpoint_Read_16_LE() >> 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); - - /* Check to see if the bank is now empty */ - if (!(Endpoint_IsReadWriteAllowed())) - { - /* Acknowledge the packet, clear the bank ready for the next packet */ - Endpoint_ClearOUT(); - } - - #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); -} - |