-/*\r
- LUFA Library\r
- Copyright (C) Dean Camera, 2009.\r
- \r
- dean [at] fourwalledcubicle [dot] com\r
- www.fourwalledcubicle.com\r
-*/\r
-\r
-/*\r
- Copyright 2009 Dean Camera (dean [at] fourwalledcubicle [dot] com)\r
-\r
- Permission to use, copy, modify, and distribute this software\r
- and its documentation for any purpose and without fee is hereby\r
- granted, provided that the above copyright notice appear in all\r
- copies and that both that the copyright notice and this\r
- permission notice and warranty disclaimer appear in supporting\r
- documentation, and that the name of the author not be used in\r
- advertising or publicity pertaining to distribution of the\r
- software without specific, written prior permission.\r
-\r
- The author disclaim all warranties with regard to this\r
- software, including all implied warranties of merchantability\r
- and fitness. In no event shall the author be liable for any\r
- special, indirect or consequential damages or any damages\r
- whatsoever resulting from loss of use, data or profits, whether\r
- in an action of contract, negligence or other tortious action,\r
- arising out of or in connection with the use or performance of\r
- this software.\r
-*/\r
-\r
-/** \file\r
- *\r
- * Main source file for the Audio Output demo. This file contains the main tasks of the demo and\r
- * is responsible for the initial application hardware configuration.\r
- */\r
- \r
-#include "AudioOutput.h"\r
-\r
-/** Flag to indicate if the streaming audio alternative interface has been selected by the host. */\r
-bool StreamingAudioInterfaceSelected = false;\r
-\r
-/** Main program entry point. This routine contains the overall program flow, including initial\r
- * setup of all components and the main program loop.\r
- */\r
-int main(void)\r
-{\r
- SetupHardware();\r
-\r
- LEDs_SetAllLEDs(LEDMASK_USB_NOTREADY);\r
- \r
- for (;;)\r
- {\r
- USB_Audio_Task();\r
- USB_USBTask();\r
- }\r
-}\r
-\r
-/** Configures the board hardware and chip peripherals for the demo's functionality. */\r
-void SetupHardware(void)\r
-{\r
- /* Disable watchdog if enabled by bootloader/fuses */\r
- MCUSR &= ~(1 << WDRF);\r
- wdt_disable();\r
-\r
- /* Disable clock division */\r
- clock_prescale_set(clock_div_1);\r
- \r
- /* Hardware Initialization */\r
- LEDs_Init();\r
- USB_Init();\r
-}\r
-\r
-/** Event handler for the USB_Connect event. This indicates that the device is enumerating via the status LEDs, and\r
- * configures the sample update and PWM timers.\r
- */\r
-void EVENT_USB_Connect(void)\r
-{\r
- /* Indicate USB enumerating */\r
- LEDs_SetAllLEDs(LEDMASK_USB_ENUMERATING);\r
- \r
- /* Sample reload timer initialization */\r
- OCR0A = (F_CPU / AUDIO_SAMPLE_FREQUENCY) - 1;\r
- TCCR0A = (1 << WGM01); // CTC mode\r
- TCCR0B = (1 << CS00); // Fcpu speed\r
- \r
-#if defined(AUDIO_OUT_MONO)\r
- /* Set speaker as output */\r
- DDRC |= (1 << 6);\r
-#elif defined(AUDIO_OUT_STEREO)\r
- /* Set speakers as outputs */\r
- DDRC |= ((1 << 6) | (1 << 5));\r
-#elif defined(AUDIO_OUT_PORTC)\r
- /* Set PORTC as outputs */\r
- DDRC |= 0xFF;\r
-#endif\r
-\r
-#if (defined(AUDIO_OUT_MONO) || defined(AUDIO_OUT_STEREO))\r
- /* PWM speaker timer initialization */\r
- TCCRxA = ((1 << WGMx0) | (1 << COMxA1) | (1 << COMxA0)\r
- | (1 << COMxB1) | (1 << COMxB0)); // Set on match, clear on TOP\r
- TCCRxB = ((1 << WGMx2) | (1 << CSx0)); // Fast 8-Bit PWM, Fcpu speed\r
-#endif \r
-}\r
-\r
-/** Event handler for the USB_Disconnect event. This indicates that the device is no longer connected to a host via\r
- * the status LEDs, disables the sample update and PWM output timers and stops the USB and Audio management tasks.\r
- */\r
-void EVENT_USB_Disconnect(void)\r
-{\r
- /* Stop the timers */\r
- TCCR0B = 0;\r
-#if (defined(AUDIO_OUT_MONO) || defined(AUDIO_OUT_STEREO))\r
- TCCRxB = 0;\r
-#endif \r
-\r
-#if defined(AUDIO_OUT_MONO)\r
- /* Set speaker as input to reduce current draw */\r
- DDRC &= ~(1 << 6);\r
-#elif defined(AUDIO_OUT_STEREO)\r
- /* Set speakers as inputs to reduce current draw */\r
- DDRC &= ~((1 << 6) | (1 << 5));\r
-#elif defined(AUDIO_OUT_PORTC)\r
- /* Set PORTC low */\r
- PORTC = 0x00;\r
-#endif\r
-\r
- /* Indicate streaming audio interface not selected */\r
- StreamingAudioInterfaceSelected = false;\r
-\r
- /* Indicate USB not ready */\r
- LEDs_SetAllLEDs(LEDMASK_USB_NOTREADY);\r
-}\r
-\r
-/** Event handler for the USB_ConfigurationChanged event. This is fired when the host set the current configuration\r
- * of the USB device after enumeration - the device endpoints are configured.\r
- */\r
-void EVENT_USB_ConfigurationChanged(void)\r
-{\r
- /* Setup audio stream endpoint */\r
- Endpoint_ConfigureEndpoint(AUDIO_STREAM_EPNUM, EP_TYPE_ISOCHRONOUS,\r
- ENDPOINT_DIR_OUT, AUDIO_STREAM_EPSIZE,\r
- ENDPOINT_BANK_DOUBLE);\r
-\r
- /* Indicate USB connected and ready */\r
- LEDs_SetAllLEDs(LEDMASK_USB_READY);\r
-}\r
-\r
-/** Event handler for the USB_UnhandledControlPacket event. This is used to catch standard and class specific\r
- * control requests that are not handled internally by the USB library (including the Audio class-specific\r
- * requests) so that they can be handled appropriately for the application.\r
- */\r
-void EVENT_USB_UnhandledControlPacket(void)\r
-{\r
- /* Process General and Audio specific control requests */\r
- switch (USB_ControlRequest.bRequest)\r
- {\r
- case REQ_SetInterface:\r
- /* Set Interface is not handled by the library, as its function is application-specific */\r
- if (USB_ControlRequest.bmRequestType == (REQDIR_HOSTTODEVICE | REQTYPE_STANDARD | REQREC_INTERFACE))\r
- {\r
- Endpoint_ClearSETUP();\r
- \r
- /* Check if the host is enabling the audio interface (setting AlternateSetting to 1) */\r
- StreamingAudioInterfaceSelected = ((USB_ControlRequest.wValue) != 0);\r
- \r
- /* Acknowledge status stage */\r
- while (!(Endpoint_IsINReady()));\r
- Endpoint_ClearIN();\r
- }\r
-\r
- break;\r
- }\r
-}\r
-\r
-/** Task to manage the Audio interface, reading in audio samples from the host, and outputting them to the speakers/LEDs as\r
- * desired.\r
- */\r
-void USB_Audio_Task(void)\r
-{\r
- /* Check to see if the streaming interface is selected, if not the host is not receiving audio */\r
- if (!(StreamingAudioInterfaceSelected))\r
- return; \r
-\r
- /* Select the audio stream endpoint */\r
- Endpoint_SelectEndpoint(AUDIO_STREAM_EPNUM);\r
- \r
- /* Check if the current endpoint can be read from (contains a packet) and that the next sample should be read */\r
- if (Endpoint_IsOUTReceived() && (TIFR0 & (1 << OCF0A)))\r
- {\r
- /* Clear the sample reload timer */\r
- TIFR0 |= (1 << OCF0A);\r
-\r
- /* Retrieve the signed 16-bit left and right audio samples */\r
- int16_t LeftSample_16Bit = (int16_t)Endpoint_Read_Word_LE();\r
- int16_t RightSample_16Bit = (int16_t)Endpoint_Read_Word_LE();\r
-\r
- /* Check to see if the bank is now empty */\r
- if (!(Endpoint_IsReadWriteAllowed()))\r
- {\r
- /* Acknowledge the packet, clear the bank ready for the next packet */\r
- Endpoint_ClearOUT();\r
- }\r
-\r
- /* Massage signed 16-bit left and right audio samples into signed 8-bit */\r
- int8_t LeftSample_8Bit = (LeftSample_16Bit >> 8);\r
- int8_t RightSample_8Bit = (RightSample_16Bit >> 8);\r
- \r
-#if defined(AUDIO_OUT_MONO)\r
- /* Mix the two channels together to produce a mono, 8-bit sample */\r
- int8_t MixedSample_8Bit = (((int16_t)LeftSample_8Bit + (int16_t)RightSample_8Bit) >> 1);\r
-\r
- /* Load the sample into the PWM timer channel */\r
- OCRxA = ((uint8_t)MixedSample_8Bit ^ (1 << 7));\r
-#elif defined(AUDIO_OUT_STEREO)\r
- /* Load the dual 8-bit samples into the PWM timer channels */\r
- OCRxA = ((uint8_t)LeftSample_8Bit ^ (1 << 7));\r
- OCRxB = ((uint8_t)RightSample_8Bit ^ (1 << 7));\r
-#elif defined(AUDIO_OUT_PORTC)\r
- /* Mix the two channels together to produce a mono, 8-bit sample */\r
- int8_t MixedSample_8Bit = (((int16_t)LeftSample_8Bit + (int16_t)RightSample_8Bit) >> 1);\r
-\r
- PORTC = MixedSample_8Bit;\r
-#else\r
- uint8_t LEDMask = LEDS_NO_LEDS;\r
-\r
- /* Make left channel positive (absolute) */\r
- if (LeftSample_8Bit < 0)\r
- LeftSample_8Bit = -LeftSample_8Bit;\r
-\r
- /* Make right channel positive (absolute) */\r
- if (RightSample_8Bit < 0)\r
- RightSample_8Bit = -RightSample_8Bit;\r
-\r
- /* Set first LED based on sample value */\r
- if (LeftSample_8Bit < ((128 / 8) * 1))\r
- LEDMask |= LEDS_LED2;\r
- else if (LeftSample_8Bit < ((128 / 8) * 3))\r
- LEDMask |= (LEDS_LED1 | LEDS_LED2);\r
- else\r
- LEDMask |= LEDS_LED1;\r
-\r
- /* Set second LED based on sample value */\r
- if (RightSample_8Bit < ((128 / 8) * 1))\r
- LEDMask |= LEDS_LED4;\r
- else if (RightSample_8Bit < ((128 / 8) * 3))\r
- LEDMask |= (LEDS_LED3 | LEDS_LED4);\r
- else\r
- LEDMask |= LEDS_LED3;\r
- \r
- LEDs_SetAllLEDs(LEDMask);\r
-#endif\r
- }\r
-}\r
+/*
+ LUFA Library
+ Copyright (C) Dean Camera, 2012.
+
+ dean [at] fourwalledcubicle [dot] com
+ www.lufa-lib.org
+*/
+
+/*
+ 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
+ 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"
+
+/** 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);
+ sei();
+
+ for (;;)
+ {
+ 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();
+}
+
+/** 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_EPNUM, EP_TYPE_ISOCHRONOUS, ENDPOINT_DIR_OUT,
+ AUDIO_STREAM_EPSIZE, ENDPOINT_BANK_DOUBLE);
+
+ /* 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 == (ENDPOINT_DIR_OUT | AUDIO_STREAM_EPNUM)) && (EndpointControl == AUDIO_EPCONTROL_SamplingFreq))
+ {
+ uint8_t SampleRate[3];
+
+ Endpoint_ClearSETUP();
+ Endpoint_Read_Control_Stream_LE(SampleRate, sizeof(SampleRate));
+ Endpoint_ClearOUT();
+
+ /* 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_HOSTTODEVICE | 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 == (ENDPOINT_DIR_OUT | AUDIO_STREAM_EPNUM)) && (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_EPNUM);
+
+ /* 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);
+}
+