Projects/Incomplete/MIDIToneGenerator/MIDIToneGenerator.c

   1 /*
   2              LUFA Library
   3      Copyright (C) Dean Camera, 2010.
   4
   5   dean [at] fourwalledcubicle [dot] com
   6       www.fourwalledcubicle.com
   7 */
   8
   9 /*
  10   Copyright 2010  Dean Camera (dean [at] fourwalledcubicle [dot] com)
  11
  12   Permission to use, copy, modify, distribute, and sell this
  13   software and its documentation for any purpose is hereby granted
  14   without fee, provided that the above copyright notice appear in
  15   all copies and that both that the copyright notice and this
  16   permission notice and warranty disclaimer appear in supporting
  17   documentation, and that the name of the author not be used in
  18   advertising or publicity pertaining to distribution of the
  19   software without specific, written prior permission.
  20
  21   The author disclaim all warranties with regard to this
  22   software, including all implied warranties of merchantability
  23   and fitness.  In no event shall the author be liable for any
  24   special, indirect or consequential damages or any damages
  25   whatsoever resulting from loss of use, data or profits, whether
  26   in an action of contract, negligence or other tortious action,
  27   arising out of or in connection with the use or performance of
  28   this software.
  29 */
  30
  31 /** \file
  32  *
  33  *  Main source file for the MIDI demo. This file contains the main tasks of
  34  *  the demo and is responsible for the initial application hardware configuration.
  35  */
  36
  37 #include "MIDIToneGenerator.h"
  38
  39 /** LUFA MIDI Class driver interface configuration and state information. This structure is
  40  *  passed to all MIDI Class driver functions, so that multiple instances of the same class
  41  *  within a device can be differentiated from one another.
  42  */
  43 USB_ClassInfo_MIDI_Device_t Keyboard_MIDI_Interface =
  44         {
  45                 .Config =
  46                         {
  47                                 .StreamingInterfaceNumber = 1,
  48
  49                                 .DataINEndpointNumber      = MIDI_STREAM_IN_EPNUM,
  50                                 .DataINEndpointSize        = MIDI_STREAM_EPSIZE,
  51                                 .DataINEndpointDoubleBank  = false,
  52
  53                                 .DataOUTEndpointNumber     = MIDI_STREAM_OUT_EPNUM,
  54                                 .DataOUTEndpointSize       = MIDI_STREAM_EPSIZE,
  55                                 .DataOUTEndpointDoubleBank = false,
  56                         },
  57         };
  58
  59 const uint8_t SineTable[] PROGMEM =
  60 {
  61         0x80, 0x83, 0x86, 0x89, 0x8c, 0x8f, 0x92, 0x95, 0x98, 0x9c, 0x9f, 0xa2, 0xa5, 0xa8, 0xab, 0xae,
  62         0xb0, 0xb3, 0xb6, 0xb9, 0xbc, 0xbf, 0xc1, 0xc4, 0xc7, 0xc9, 0xcc, 0xce, 0xd1, 0xd3, 0xd5, 0xd8,
  63         0xda, 0xdc, 0xde, 0xe0, 0xe2, 0xe4, 0xe6, 0xe8, 0xea, 0xec, 0xed, 0xef, 0xf0, 0xf2, 0xf3, 0xf5,
  64         0xf6, 0xf7, 0xf8, 0xf9, 0xfa, 0xfb, 0xfc, 0xfc, 0xfd, 0xfe, 0xfe, 0xff, 0xff, 0xff, 0xff, 0xff,
  65         0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xfe, 0xfe, 0xfd, 0xfc, 0xfc, 0xfb, 0xfa, 0xf9, 0xf8, 0xf7,
  66         0xf6, 0xf5, 0xf3, 0xf2, 0xf0, 0xef, 0xed, 0xec, 0xea, 0xe8, 0xe6, 0xe4, 0xe2, 0xe0, 0xde, 0xdc,
  67         0xda, 0xd8, 0xd5, 0xd3, 0xd1, 0xce, 0xcc, 0xc9, 0xc7, 0xc4, 0xc1, 0xbf, 0xbc, 0xb9, 0xb6, 0xb3,
  68         0xb0, 0xae, 0xab, 0xa8, 0xa5, 0xa2, 0x9f, 0x9c, 0x98, 0x95, 0x92, 0x8f, 0x8c, 0x89, 0x86, 0x83,
  69         0x80, 0x7c, 0x79, 0x76, 0x73, 0x70, 0x6d, 0x6a, 0x67, 0x63, 0x60, 0x5d, 0x5a, 0x57, 0x54, 0x51,
  70         0x4f, 0x4c, 0x49, 0x46, 0x43, 0x40, 0x3e, 0x3b, 0x38, 0x36, 0x33, 0x31, 0x2e, 0x2c, 0x2a, 0x27,
  71         0x25, 0x23, 0x21, 0x1f, 0x1d, 0x1b, 0x19, 0x17, 0x15, 0x13, 0x12, 0x10, 0x0f, 0x0d, 0x0c, 0x0a,
  72         0x09, 0x08, 0x07, 0x06, 0x05, 0x04, 0x03, 0x03, 0x02, 0x01, 0x01, 0x00, 0x00, 0x00, 0x00, 0x00,
  73         0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01, 0x01, 0x02, 0x03, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08,
  74         0x09, 0x0a, 0x0c, 0x0d, 0x0f, 0x10, 0x12, 0x13, 0x15, 0x17, 0x19, 0x1b, 0x1d, 0x1f, 0x21, 0x23,
  75         0x25, 0x27, 0x2a, 0x2c, 0x2e, 0x31, 0x33, 0x36, 0x38, 0x3b, 0x3e, 0x40, 0x43, 0x46, 0x49, 0x4c,
  76         0x4f, 0x51, 0x54, 0x57, 0x5a, 0x5d, 0x60, 0x63, 0x67, 0x6a, 0x6d, 0x70, 0x73, 0x76, 0x79, 0x7c
  77 };
  78
  79 struct
  80 {
  81         uint8_t Pitch;
  82         uint8_t Velocity;
  83
  84         uint8_t CurrentPos;
  85         uint8_t ElapsedTicks;
  86 } ChannelStates[10];
  87
  88 /** Main program entry point. This routine contains the overall program flow, including initial
  89  *  setup of all components and the main program loop.
  90  */
  91 int main(void)
  92 {
  93         SetupHardware();
  94
  95         LEDs_SetAllLEDs(LEDMASK_USB_NOTREADY);
  96
  97         for (;;)
  98         {
  99                 MIDI_EventPacket_t ReceivedMIDIEvent;
 100                 if (MIDI_Device_ReceiveEventPacket(&Keyboard_MIDI_Interface, &ReceivedMIDIEvent))
 101                 {
 102                         if (ReceivedMIDIEvent.Command == (MIDI_COMMAND_NOTE_ON >> 4))
 103                         {
 104                                 ChannelStates[ReceivedMIDIEvent.Data1 & 0x0F].Pitch    = ReceivedMIDIEvent.Data2;
 105                                 ChannelStates[ReceivedMIDIEvent.Data1 & 0x0F].Velocity = ReceivedMIDIEvent.Data3;
 106
 107                                 LEDs_SetAllLEDs(LEDS_LED1);
 108                         }
 109                         else if (ReceivedMIDIEvent.Command == (MIDI_COMMAND_NOTE_OFF >> 4))
 110                         {
 111                                 ChannelStates[ReceivedMIDIEvent.Data1 & 0x0F].Velocity = 0;
 112
 113                                 LEDs_SetAllLEDs(LEDS_NO_LEDS);
 114                         }
 115                 }
 116
 117                 /* Check if the sample reload timer period has elapsed, and that the USB bus is ready for a new sample */
 118                 if (TIFR0 & (1 << OCF0A))
 119                 {
 120                         /* Clear the sample reload timer */
 121                         TIFR0 |= (1 << OCF0A);
 122
 123                         uint8_t OutputSample = 0;
 124
 125                         /* Loop through the channels (excluding percussion channel 10) and generate next sample */
 126                         for (uint8_t Channel = 0; Channel < 9; Channel++)
 127                         {
 128                                 /* Channel only contributes if it is not muted */
 129                                 if (ChannelStates[Channel].Velocity)
 130                                 {
 131                                         /* Fetch the current sample from the sine lookup table */
 132                                         uint8_t TableValue = pgm_read_byte(&SineTable[ChannelStates[Channel].CurrentPos]);
 133
 134                                         /* Scale sample value by the velocity of the channel */
 135                                         TableValue = ((uint16_t)TableValue << 6) / ChannelStates[Channel].Velocity;
 136
 137                                         /* Add the sample to the output waveform */
 138                                         OutputSample += TableValue;
 139                                 }
 140
 141                                 /* Calculate next sample table position for this channel */
 142                                 ChannelStates[Channel].CurrentPos += ChannelStates[Channel].Pitch;
 143                         }
 144
 145                         /* Output the sample to the PWM timer */
 146                         OCR3A = OutputSample;
 147                 }
 148
 149                 MIDI_Device_USBTask(&Keyboard_MIDI_Interface);
 150                 USB_USBTask();
 151         }
 152 }
 153
 154 /** Configures the board hardware and chip peripherals for the demo's functionality. */
 155 void SetupHardware(void)
 156 {
 157         /* Disable watchdog if enabled by bootloader/fuses */
 158         MCUSR &= ~(1 << WDRF);
 159         wdt_disable();
 160
 161         /* Disable clock division */
 162         clock_prescale_set(clock_div_1);
 163
 164         /* Hardware Initialization */
 165         LEDs_Init();
 166         USB_Init();
 167
 168         /* Sample reload timer initialization */
 169         OCR0A   = (F_CPU / 8 / AUDIO_SAMPLE_FREQUENCY) - 1;
 170         TCCR0A  = (1 << WGM01);  // CTC mode
 171         TCCR0B  = (1 << CS01);   // Fcpu/8 speed
 172
 173         /* PWM speaker timer initialization */
 174         TCCR3A  = ((1 << WGM30) | (1 << COM3A1) | (1 << COM3A0)); // Set on match, clear on TOP
 175         TCCR3B  = ((1 << WGM32) | (1 << CS30));  // Fast 8-Bit PWM, Fcpu speed
 176 }
 177
 178 /** Event handler for the library USB Connection event. */
 179 void EVENT_USB_Device_Connect(void)
 180 {
 181         LEDs_SetAllLEDs(LEDMASK_USB_ENUMERATING);
 182
 183         /* Set speaker as output */
 184         DDRC |= (1 << 6);
 185 }
 186
 187 /** Event handler for the library USB Disconnection event. */
 188 void EVENT_USB_Device_Disconnect(void)
 189 {
 190         LEDs_SetAllLEDs(LEDMASK_USB_NOTREADY);
 191
 192         /* Set speaker as input to reduce current draw */
 193         DDRC &= ~(1 << 6);
 194 }
 195
 196 /** Event handler for the library USB Configuration Changed event. */
 197 void EVENT_USB_Device_ConfigurationChanged(void)
 198 {
 199         LEDs_SetAllLEDs(LEDMASK_USB_READY);
 200
 201         if (!(MIDI_Device_ConfigureEndpoints(&Keyboard_MIDI_Interface)))
 202           LEDs_SetAllLEDs(LEDMASK_USB_ERROR);
 203 }
 204
 205 /** Event handler for the library USB Unhandled Control Request event. */
 206 void EVENT_USB_Device_UnhandledControlRequest(void)
 207 {
 208         MIDI_Device_ProcessControlRequest(&Keyboard_MIDI_Interface);
 209 }