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Diffstat (limited to 'lib/lufa/Projects/MIDIToneGenerator/MIDIToneGenerator.c')
| -rw-r--r-- | lib/lufa/Projects/MIDIToneGenerator/MIDIToneGenerator.c | 252 |
1 files changed, 252 insertions, 0 deletions
diff --git a/lib/lufa/Projects/MIDIToneGenerator/MIDIToneGenerator.c b/lib/lufa/Projects/MIDIToneGenerator/MIDIToneGenerator.c new file mode 100644 index 0000000000..6d9e08a19d --- /dev/null +++ b/lib/lufa/Projects/MIDIToneGenerator/MIDIToneGenerator.c @@ -0,0 +1,252 @@ +/* + 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 MIDI demo. This file contains the main tasks of + * the demo and is responsible for the initial application hardware configuration. + */ + +#include "MIDIToneGenerator.h" + +/** LUFA MIDI Class driver interface configuration and state information. This structure is + * passed to all MIDI Class driver functions, so that multiple instances of the same class + * within a device can be differentiated from one another. + */ +USB_ClassInfo_MIDI_Device_t Keyboard_MIDI_Interface = + { + .Config = + { + .StreamingInterfaceNumber = INTERFACE_ID_AudioStream, + .DataINEndpoint = + { + .Address = MIDI_STREAM_IN_EPADDR, + .Size = MIDI_STREAM_EPSIZE, + .Banks = 1, + }, + .DataOUTEndpoint = + { + .Address = MIDI_STREAM_OUT_EPADDR, + .Size = MIDI_STREAM_EPSIZE, + .Banks = 1, + }, + }, + }; + +/** 8-bit 256 entry Sine Wave lookup table */ +static const uint8_t SineTable[256] = +{ + 128, 131, 134, 137, 140, 143, 146, 149, 152, 156, 159, 162, 165, 168, 171, 174, + 176, 179, 182, 185, 188, 191, 193, 196, 199, 201, 204, 206, 209, 211, 213, 216, + 218, 220, 222, 224, 226, 228, 230, 232, 234, 236, 237, 239, 240, 242, 243, 245, + 246, 247, 248, 249, 250, 251, 252, 252, 253, 254, 254, 255, 255, 255, 255, 255, + 255, 255, 255, 255, 255, 255, 254, 254, 253, 252, 252, 251, 250, 249, 248, 247, + 246, 245, 243, 242, 240, 239, 237, 236, 234, 232, 230, 228, 226, 224, 222, 220, + 218, 216, 213, 211, 209, 206, 204, 201, 199, 196, 193, 191, 188, 185, 182, 179, + 176, 174, 171, 168, 165, 162, 159, 156, 152, 149, 146, 143, 140, 137, 134, 131, + 128, 124, 121, 118, 115, 112, 109, 106, 103, 99, 96, 93, 90, 87, 84, 81, + 79, 76, 73, 70, 67, 64, 62, 59, 56, 54, 51, 49, 46, 44, 42, 39, + 37, 35, 33, 31, 29, 27, 25, 23, 21, 19, 18, 16, 15, 13, 12, 10, + 9, 8, 7, 6, 5, 4, 3, 3, 2, 1, 1, 0, 0, 0, 0, 0, + 0, 0, 0, 0, 0, 0, 1, 1, 2, 3, 3, 4, 5, 6, 7, 8, + 9, 10, 12, 13, 15, 16, 18, 19, 21, 23, 25, 27, 29, 31, 33, 35, + 37, 39, 42, 44, 46, 49, 51, 54, 56, 59, 62, 64, 67, 70, 73, 76, + 79, 81, 84, 87, 90, 93, 96, 99, 103, 106, 109, 112, 115, 118, 121, 124, +}; + +/** Array of structures describing each note being generated */ +static DDSNoteData NoteData[MAX_SIMULTANEOUS_NOTES]; + + +/** 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 (;;) + { + MIDI_EventPacket_t ReceivedMIDIEvent; + if (MIDI_Device_ReceiveEventPacket(&Keyboard_MIDI_Interface, &ReceivedMIDIEvent)) + { + if ((ReceivedMIDIEvent.Event == MIDI_EVENT(0, MIDI_COMMAND_NOTE_ON)) && ((ReceivedMIDIEvent.Data1 & 0x0F) == 0)) + { + DDSNoteData* LRUNoteStruct = &NoteData[0]; + + /* Find a free entry in the note table to use for the note being turned on */ + for (uint8_t i = 0; i < MAX_SIMULTANEOUS_NOTES; i++) + { + /* Check if the note is unused */ + if (!(NoteData[i].Pitch)) + { + /* If a note is unused, it's age is essentially infinite - always prefer unused note entries */ + LRUNoteStruct = &NoteData[i]; + break; + } + else if (NoteData[i].LRUAge >= LRUNoteStruct->LRUAge) + { + /* If an older entry that the current entry has been found, prefer overwriting that one */ + LRUNoteStruct = &NoteData[i]; + } + + NoteData[i].LRUAge++; + } + + /* Update the oldest note entry with the new note data and reset its age */ + LRUNoteStruct->Pitch = ReceivedMIDIEvent.Data2; + LRUNoteStruct->TableIncrement = (uint32_t)(BASE_INCREMENT * SCALE_FACTOR) + + ((uint32_t)(BASE_INCREMENT * NOTE_OCTIVE_RATIO * SCALE_FACTOR) * + (ReceivedMIDIEvent.Data2 - BASE_PITCH_INDEX)); + LRUNoteStruct->TablePosition = 0; + LRUNoteStruct->LRUAge = 0; + + /* Turn on indicator LED to indicate note generation activity */ + LEDs_SetAllLEDs(LEDS_LED1); + } + else if ((ReceivedMIDIEvent.Event == MIDI_EVENT(0, MIDI_COMMAND_NOTE_OFF)) && ((ReceivedMIDIEvent.Data1 & 0x0F) == 0)) + { + bool FoundActiveNote = false; + + /* Find the note in the note table to turn off */ + for (uint8_t i = 0; i < MAX_SIMULTANEOUS_NOTES; i++) + { + if (NoteData[i].Pitch == ReceivedMIDIEvent.Data2) + NoteData[i].Pitch = 0; + else if (NoteData[i].Pitch) + FoundActiveNote = true; + } + + /* If all notes off, turn off the indicator LED */ + if (!(FoundActiveNote)) + LEDs_SetAllLEDs(LEDS_NO_LEDS); + } + } + + MIDI_Device_USBTask(&Keyboard_MIDI_Interface); + USB_USBTask(); + } +} + +/** ISR to handle the reloading of the PWM timer with the next sample. */ +ISR(TIMER0_COMPA_vect, ISR_BLOCK) +{ + uint16_t MixedSample = 0; + + /* Sum together all the active notes to form a single sample */ + for (uint8_t i = 0; i < MAX_SIMULTANEOUS_NOTES; i++) + { + /* A non-zero pitch indicates the note is active */ + if (NoteData[i].Pitch) + { + /* Use the top 8 bits of the table position as the sample table index */ + uint8_t TableIndex = (NoteData[i].TablePosition >> 24); + + /* Add the new tone sample to the accumulator and increment the table position */ + MixedSample += SineTable[TableIndex]; + NoteData[i].TablePosition += NoteData[i].TableIncrement; + } + } + + /* Output clamped mixed sample value to the PWM */ + OCR3A = (MixedSample <= 0xFF) ? MixedSample : 0xFF; +} + +/** 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(); + + /* Sample reload timer initialization */ + TIMSK0 = (1 << OCIE0A); + OCR0A = (VIRTUAL_SAMPLE_TABLE_SIZE / 8); + TCCR0A = (1 << WGM01); // CTC mode + TCCR0B = (1 << CS01); // Fcpu/8 speed + + /* Set speaker as output */ + DDRC |= (1 << 6); + + /* PWM speaker timer initialization */ + TCCR3A = ((1 << WGM31) | (1 << COM3A1) | (1 << COM3A0)); // Set on match, clear on TOP + TCCR3B = ((1 << WGM32) | (1 << CS30)); // Fast 8-Bit PWM, Fcpu speed +} + +/** Event handler for the library USB Connection event. */ +void EVENT_USB_Device_Connect(void) +{ + LEDs_SetAllLEDs(LEDMASK_USB_ENUMERATING); + + /* Set speaker as output */ + DDRC |= (1 << 6); +} + +/** Event handler for the library USB Disconnection event. */ +void EVENT_USB_Device_Disconnect(void) +{ + LEDs_SetAllLEDs(LEDMASK_USB_NOTREADY); + + /* Disable any notes currently being played */ + for (uint8_t i = 0; i < MAX_SIMULTANEOUS_NOTES; i++) + NoteData[i].Pitch = 0; + + /* Set speaker as input to reduce current draw */ + DDRC &= ~(1 << 6); +} + +/** Event handler for the library USB Configuration Changed event. */ +void EVENT_USB_Device_ConfigurationChanged(void) +{ + bool ConfigSuccess = true; + + ConfigSuccess &= MIDI_Device_ConfigureEndpoints(&Keyboard_MIDI_Interface); + + LEDs_SetAllLEDs(ConfigSuccess ? LEDMASK_USB_READY : LEDMASK_USB_ERROR); +} + +/** Event handler for the library USB Control Request event. */ +void EVENT_USB_Device_ControlRequest(void) +{ + MIDI_Device_ProcessControlRequest(&Keyboard_MIDI_Interface); +} + |