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diff --git a/digital/avr/modules/usb/lufa/Demos/AudioInput/AudioInput.c b/digital/avr/modules/usb/lufa/Demos/AudioInput/AudioInput.c
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+/*
+ LUFA Library
+ Copyright (C) Dean Camera, 2009.
+
+ dean [at] fourwalledcubicle [dot] com
+ www.fourwalledcubicle.com
+*/
+
+/*
+ Copyright 2009 Dean Camera (dean [at] fourwalledcubicle [dot] com)
+
+ Permission to use, copy, modify, and distribute this software
+ and its documentation for any purpose and without fee is hereby
+ granted, 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 Audio Input demo. This file contains the main tasks of the demo and
+ * is responsible for the initial application hardware configuration.
+ */
+
+/* --- Project Configuration --- */
+//#define MICROPHONE_BIASED_TO_HALF_RAIL
+/* --- --- --- --- --- --- --- --- */
+
+#include "AudioInput.h"
+
+/* Project Tags, for reading out using the ButtLoad project */
+BUTTLOADTAG(ProjName, "LUFA AudioIn App");
+BUTTLOADTAG(BuildTime, __TIME__);
+BUTTLOADTAG(BuildDate, __DATE__);
+BUTTLOADTAG(LUFAVersion, "LUFA V" LUFA_VERSION_STRING);
+
+/* Scheduler Task List */
+TASK_LIST
+{
+ { Task: USB_USBTask , TaskStatus: TASK_STOP },
+ { Task: USB_Audio_Task , TaskStatus: TASK_STOP },
+};
+
+
+/** Main program entry point. This routine configures the hardware required by the application, then
+ * starts the scheduler to run the application tasks.
+ */
+int main(void)
+{
+ /* Disable watchdog if enabled by bootloader/fuses */
+ MCUSR &= ~(1 << WDRF);
+ wdt_disable();
+
+ /* Disable Clock Division */
+ SetSystemClockPrescaler(0);
+
+ /* Hardware Initialization */
+ LEDs_Init();
+ ADC_Init(ADC_FREE_RUNNING | ADC_PRESCALE_32);
+ ADC_SetupChannel(MIC_IN_ADC_CHANNEL);
+
+ /* Start the ADC conversion in free running mode */
+ ADC_StartReading(ADC_REFERENCE_AVCC | ADC_RIGHT_ADJUSTED | MIC_IN_ADC_CHANNEL);
+
+ /* Indicate USB not ready */
+ UpdateStatus(Status_USBNotReady);
+
+ /* Initialize Scheduler so that it can be used */
+ Scheduler_Init();
+
+ /* Initialize USB Subsystem */
+ USB_Init();
+
+ /* Scheduling - routine never returns, so put this last in the main function */
+ Scheduler_Start();
+}
+
+/** 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.
+ */
+EVENT_HANDLER(USB_Connect)
+{
+ /* Start USB management task */
+ Scheduler_SetTaskMode(USB_USBTask, TASK_RUN);
+
+ /* Indicate USB enumerating */
+ UpdateStatus(Status_USBEnumerating);
+
+ /* Sample reload timer initialization */
+ OCR0A = (F_CPU / AUDIO_SAMPLE_FREQUENCY);
+ TCCR0A = (1 << WGM01); // CTC mode
+ TCCR0B = (1 << CS00); // Fcpu speed
+}
+
+/** 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.
+ */
+EVENT_HANDLER(USB_Disconnect)
+{
+ /* Stop the sample reload timer */
+ TCCR0B = 0;
+
+ /* Stop running audio and USB management tasks */
+ Scheduler_SetTaskMode(USB_Audio_Task, TASK_STOP);
+ Scheduler_SetTaskMode(USB_USBTask, TASK_STOP);
+
+ /* Indicate USB not ready */
+ UpdateStatus(Status_USBNotReady);
+}
+
+/** 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.
+ */
+EVENT_HANDLER(USB_ConfigurationChanged)
+{
+ /* Setup audio stream endpoint */
+ Endpoint_ConfigureEndpoint(AUDIO_STREAM_EPNUM, EP_TYPE_ISOCHRONOUS,
+ ENDPOINT_DIR_IN, AUDIO_STREAM_EPSIZE,
+ ENDPOINT_BANK_DOUBLE);
+
+ /* Indicate USB connected and ready */
+ UpdateStatus(Status_USBReady);
+}
+
+/** Event handler for the USB_UnhandledControlPacket event. This is used to catch standard and class specific
+ * control requests that are not handled internally by the USB library (including the Audio class-specific
+ * requests) so that they can be handled appropriately for the application.
+ */
+EVENT_HANDLER(USB_UnhandledControlPacket)
+{
+ /* Process General and Audio specific control requests */
+ switch (bRequest)
+ {
+ case REQ_SetInterface:
+ /* Set Interface is not handled by the library, as its function is application-specific */
+ if (bmRequestType == (REQDIR_HOSTTODEVICE | REQTYPE_STANDARD | REQREC_INTERFACE))
+ {
+ uint16_t wValue = Endpoint_Read_Word_LE();
+
+ Endpoint_ClearSetupReceived();
+
+ /* Check if the host is enabling the audio interface (setting AlternateSetting to 1) */
+ if (wValue)
+ {
+ /* Start audio task */
+ Scheduler_SetTaskMode(USB_Audio_Task, TASK_RUN);
+ }
+ else
+ {
+ /* Stop audio task */
+ Scheduler_SetTaskMode(USB_Audio_Task, TASK_STOP);
+ }
+
+ /* Handshake the request */
+ Endpoint_ClearSetupIN();
+ }
+
+ break;
+ }
+}
+
+/** Function to manage status updates to the user. This is done via LEDs on the given board, if available, but may be changed to
+ * log to a serial port, or anything else that is suitable for status updates.
+ *
+ * \param CurrentStatus Current status of the system, from the AudioInput_StatusCodes_t enum
+ */
+void UpdateStatus(uint8_t CurrentStatus)
+{
+ uint8_t LEDMask = LEDS_NO_LEDS;
+
+ /* Set the LED mask to the appropriate LED mask based on the given status code */
+ switch (CurrentStatus)
+ {
+ case Status_USBNotReady:
+ LEDMask = (LEDS_LED1);
+ break;
+ case Status_USBEnumerating:
+ LEDMask = (LEDS_LED1 | LEDS_LED2);
+ break;
+ case Status_USBReady:
+ LEDMask = (LEDS_LED2 | LEDS_LED4);
+ break;
+ }
+
+ /* Set the board LEDs to the new LED mask */
+ LEDs_SetAllLEDs(LEDMask);
+}
+
+/** Task to manage the Audio interface, reading in ADC samples from the microphone, and them to the host. */
+TASK(USB_Audio_Task)
+{
+ /* Select the audio stream endpoint */
+ Endpoint_SelectEndpoint(AUDIO_STREAM_EPNUM);
+
+ /* Check if the current endpoint can be read from (contains a packet) and that the next sample should be stored */
+ if (Endpoint_ReadWriteAllowed() && (TIFR0 & (1 << OCF0A)))
+ {
+ /* Clear the sample reload timer */
+ TIFR0 |= (1 << OCF0A);
+
+ /* Audio sample is ADC value scaled to fit the entire range */
+ int16_t AudioSample = ((SAMPLE_MAX_RANGE / ADC_MAX_RANGE) * ADC_GetResult());
+
+#if defined(MICROPHONE_BIASED_TO_HALF_RAIL)
+ /* Microphone is biased to half rail voltage, subtract the bias from the sample value */
+ AudioSample -= (SAMPLE_MAX_RANGE / 2));
+#endif
+
+ /* Write the sample to the buffer */
+ Endpoint_Write_Word_LE(AudioSample);
+
+ /* Check to see if the bank is now full */
+ if (!(Endpoint_ReadWriteAllowed()))
+ {
+ /* Send the full packet to the host */
+ Endpoint_ClearCurrentBank();
+ }
+ }
+}