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diff --git a/lib/lufa/Demos/Device/LowLevel/AudioOutput/AudioOutput.c b/lib/lufa/Demos/Device/LowLevel/AudioOutput/AudioOutput.c
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+/*
+ 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);
+}
+