253 lines
8.4 KiB
C
253 lines
8.4 KiB
C
/*
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LUFA Library
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Copyright (C) Dean Camera, 2017.
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dean [at] fourwalledcubicle [dot] com
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www.lufa-lib.org
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*/
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/*
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Copyright 2017 Dean Camera (dean [at] fourwalledcubicle [dot] com)
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Permission to use, copy, modify, distribute, and sell this
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software and its documentation for any purpose is hereby granted
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without fee, provided that the above copyright notice appear in
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all copies and that both that the copyright notice and this
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permission notice and warranty disclaimer appear in supporting
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documentation, and that the name of the author not be used in
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advertising or publicity pertaining to distribution of the
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software without specific, written prior permission.
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The author disclaims all warranties with regard to this
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software, including all implied warranties of merchantability
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and fitness. In no event shall the author be liable for any
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special, indirect or consequential damages or any damages
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whatsoever resulting from loss of use, data or profits, whether
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in an action of contract, negligence or other tortious action,
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arising out of or in connection with the use or performance of
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this software.
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*/
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/** \file
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*
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* Main source file for the MIDI demo. This file contains the main tasks of
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* the demo and is responsible for the initial application hardware configuration.
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*/
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#include "MIDIToneGenerator.h"
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/** LUFA MIDI Class driver interface configuration and state information. This structure is
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* passed to all MIDI Class driver functions, so that multiple instances of the same class
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* within a device can be differentiated from one another.
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*/
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USB_ClassInfo_MIDI_Device_t Keyboard_MIDI_Interface =
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{
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.Config =
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{
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.StreamingInterfaceNumber = INTERFACE_ID_AudioStream,
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.DataINEndpoint =
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{
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.Address = MIDI_STREAM_IN_EPADDR,
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.Size = MIDI_STREAM_EPSIZE,
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.Banks = 1,
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},
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.DataOUTEndpoint =
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{
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.Address = MIDI_STREAM_OUT_EPADDR,
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.Size = MIDI_STREAM_EPSIZE,
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.Banks = 1,
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},
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},
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};
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/** 8-bit 256 entry Sine Wave lookup table */
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static const uint8_t SineTable[256] =
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{
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128, 131, 134, 137, 140, 143, 146, 149, 152, 156, 159, 162, 165, 168, 171, 174,
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176, 179, 182, 185, 188, 191, 193, 196, 199, 201, 204, 206, 209, 211, 213, 216,
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218, 220, 222, 224, 226, 228, 230, 232, 234, 236, 237, 239, 240, 242, 243, 245,
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246, 247, 248, 249, 250, 251, 252, 252, 253, 254, 254, 255, 255, 255, 255, 255,
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255, 255, 255, 255, 255, 255, 254, 254, 253, 252, 252, 251, 250, 249, 248, 247,
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246, 245, 243, 242, 240, 239, 237, 236, 234, 232, 230, 228, 226, 224, 222, 220,
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218, 216, 213, 211, 209, 206, 204, 201, 199, 196, 193, 191, 188, 185, 182, 179,
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176, 174, 171, 168, 165, 162, 159, 156, 152, 149, 146, 143, 140, 137, 134, 131,
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128, 124, 121, 118, 115, 112, 109, 106, 103, 99, 96, 93, 90, 87, 84, 81,
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79, 76, 73, 70, 67, 64, 62, 59, 56, 54, 51, 49, 46, 44, 42, 39,
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37, 35, 33, 31, 29, 27, 25, 23, 21, 19, 18, 16, 15, 13, 12, 10,
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9, 8, 7, 6, 5, 4, 3, 3, 2, 1, 1, 0, 0, 0, 0, 0,
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0, 0, 0, 0, 0, 0, 1, 1, 2, 3, 3, 4, 5, 6, 7, 8,
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9, 10, 12, 13, 15, 16, 18, 19, 21, 23, 25, 27, 29, 31, 33, 35,
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37, 39, 42, 44, 46, 49, 51, 54, 56, 59, 62, 64, 67, 70, 73, 76,
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79, 81, 84, 87, 90, 93, 96, 99, 103, 106, 109, 112, 115, 118, 121, 124,
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};
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/** Array of structures describing each note being generated */
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static DDSNoteData NoteData[MAX_SIMULTANEOUS_NOTES];
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/** Main program entry point. This routine contains the overall program flow, including initial
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* setup of all components and the main program loop.
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*/
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int main(void)
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{
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SetupHardware();
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LEDs_SetAllLEDs(LEDMASK_USB_NOTREADY);
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GlobalInterruptEnable();
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for (;;)
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{
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MIDI_EventPacket_t ReceivedMIDIEvent;
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if (MIDI_Device_ReceiveEventPacket(&Keyboard_MIDI_Interface, &ReceivedMIDIEvent))
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{
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if ((ReceivedMIDIEvent.Event == MIDI_EVENT(0, MIDI_COMMAND_NOTE_ON)) && ((ReceivedMIDIEvent.Data1 & 0x0F) == 0))
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{
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DDSNoteData* LRUNoteStruct = &NoteData[0];
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/* Find a free entry in the note table to use for the note being turned on */
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for (uint8_t i = 0; i < MAX_SIMULTANEOUS_NOTES; i++)
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{
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/* Check if the note is unused */
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if (!(NoteData[i].Pitch))
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{
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/* If a note is unused, it's age is essentially infinite - always prefer unused note entries */
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LRUNoteStruct = &NoteData[i];
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break;
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}
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else if (NoteData[i].LRUAge >= LRUNoteStruct->LRUAge)
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{
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/* If an older entry that the current entry has been found, prefer overwriting that one */
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LRUNoteStruct = &NoteData[i];
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}
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NoteData[i].LRUAge++;
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}
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/* Update the oldest note entry with the new note data and reset its age */
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LRUNoteStruct->Pitch = ReceivedMIDIEvent.Data2;
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LRUNoteStruct->TableIncrement = (uint32_t)(BASE_INCREMENT * SCALE_FACTOR) +
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((uint32_t)(BASE_INCREMENT * NOTE_OCTIVE_RATIO * SCALE_FACTOR) *
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(ReceivedMIDIEvent.Data2 - BASE_PITCH_INDEX));
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LRUNoteStruct->TablePosition = 0;
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LRUNoteStruct->LRUAge = 0;
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/* Turn on indicator LED to indicate note generation activity */
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LEDs_SetAllLEDs(LEDS_LED1);
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}
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else if ((ReceivedMIDIEvent.Event == MIDI_EVENT(0, MIDI_COMMAND_NOTE_OFF)) && ((ReceivedMIDIEvent.Data1 & 0x0F) == 0))
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{
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bool FoundActiveNote = false;
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/* Find the note in the note table to turn off */
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for (uint8_t i = 0; i < MAX_SIMULTANEOUS_NOTES; i++)
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{
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if (NoteData[i].Pitch == ReceivedMIDIEvent.Data2)
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NoteData[i].Pitch = 0;
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else if (NoteData[i].Pitch)
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FoundActiveNote = true;
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}
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/* If all notes off, turn off the indicator LED */
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if (!(FoundActiveNote))
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LEDs_SetAllLEDs(LEDS_NO_LEDS);
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}
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}
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MIDI_Device_USBTask(&Keyboard_MIDI_Interface);
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USB_USBTask();
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}
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}
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/** ISR to handle the reloading of the PWM timer with the next sample. */
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ISR(TIMER0_COMPA_vect, ISR_BLOCK)
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{
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uint16_t MixedSample = 0;
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/* Sum together all the active notes to form a single sample */
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for (uint8_t i = 0; i < MAX_SIMULTANEOUS_NOTES; i++)
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{
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/* A non-zero pitch indicates the note is active */
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if (NoteData[i].Pitch)
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{
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/* Use the top 8 bits of the table position as the sample table index */
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uint8_t TableIndex = (NoteData[i].TablePosition >> 24);
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/* Add the new tone sample to the accumulator and increment the table position */
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MixedSample += SineTable[TableIndex];
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NoteData[i].TablePosition += NoteData[i].TableIncrement;
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}
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}
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/* Output clamped mixed sample value to the PWM */
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OCR3A = (MixedSample <= 0xFF) ? MixedSample : 0xFF;
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}
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/** Configures the board hardware and chip peripherals for the demo's functionality. */
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void SetupHardware(void)
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{
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#if (ARCH == ARCH_AVR8)
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/* Disable watchdog if enabled by bootloader/fuses */
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MCUSR &= ~(1 << WDRF);
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wdt_disable();
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/* Disable clock division */
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clock_prescale_set(clock_div_1);
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#endif
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/* Hardware Initialization */
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LEDs_Init();
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USB_Init();
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/* Sample reload timer initialization */
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TIMSK0 = (1 << OCIE0A);
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OCR0A = (VIRTUAL_SAMPLE_TABLE_SIZE / 8);
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TCCR0A = (1 << WGM01); // CTC mode
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TCCR0B = (1 << CS01); // Fcpu/8 speed
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/* Set speaker as output */
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DDRC |= (1 << 6);
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/* PWM speaker timer initialization */
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TCCR3A = ((1 << WGM31) | (1 << COM3A1) | (1 << COM3A0)); // Set on match, clear on TOP
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TCCR3B = ((1 << WGM32) | (1 << CS30)); // Fast 8-Bit PWM, Fcpu speed
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}
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/** Event handler for the library USB Connection event. */
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void EVENT_USB_Device_Connect(void)
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{
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LEDs_SetAllLEDs(LEDMASK_USB_ENUMERATING);
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/* Set speaker as output */
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DDRC |= (1 << 6);
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}
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/** Event handler for the library USB Disconnection event. */
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void EVENT_USB_Device_Disconnect(void)
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{
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LEDs_SetAllLEDs(LEDMASK_USB_NOTREADY);
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/* Disable any notes currently being played */
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for (uint8_t i = 0; i < MAX_SIMULTANEOUS_NOTES; i++)
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NoteData[i].Pitch = 0;
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/* Set speaker as input to reduce current draw */
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DDRC &= ~(1 << 6);
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}
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/** Event handler for the library USB Configuration Changed event. */
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void EVENT_USB_Device_ConfigurationChanged(void)
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{
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bool ConfigSuccess = true;
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ConfigSuccess &= MIDI_Device_ConfigureEndpoints(&Keyboard_MIDI_Interface);
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LEDs_SetAllLEDs(ConfigSuccess ? LEDMASK_USB_READY : LEDMASK_USB_ERROR);
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}
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/** Event handler for the library USB Control Request event. */
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void EVENT_USB_Device_ControlRequest(void)
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{
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MIDI_Device_ProcessControlRequest(&Keyboard_MIDI_Interface);
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}
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