Demos/Device/LowLevel/MIDI/MIDI.c

   1 /*
   2              LUFA Library
   3      Copyright (C) Dean Camera, 2009.
   4
   5   dean [at] fourwalledcubicle [dot] com
   6       www.fourwalledcubicle.com
   7 */
   8
   9 /*
  10   Copyright 2009  Dean Camera (dean [at] fourwalledcubicle [dot] com)
  11
  12   Permission to use, copy, modify, and distribute this software
  13   and its documentation for any purpose and without fee is hereby
  14   granted, provided that the above copyright notice appear in all
  15   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 input demo. This file contains the main tasks of the demo and
  34  *  is responsible for the initial application hardware configuration.
  35  */
  36
  37 #include "MIDI.h"
  38
  39 /** Main program entry point. This routine configures the hardware required by the application, then
  40  *  starts the scheduler to run the application tasks.
  41  */
  42 int main(void)
  43 {
  44         SetupHardware();
  45
  46         LEDs_SetAllLEDs(LEDMASK_USB_NOTREADY);
  47
  48         for (;;)
  49         {
  50                 MIDI_Task();
  51                 USB_USBTask();
  52         }
  53 }
  54
  55 /** Configures the board hardware and chip peripherals for the demo's functionality. */
  56 void SetupHardware(void)
  57 {
  58         /* Disable watchdog if enabled by bootloader/fuses */
  59         MCUSR &= ~(1 << WDRF);
  60         wdt_disable();
  61
  62         /* Disable clock division */
  63         clock_prescale_set(clock_div_1);
  64
  65         /* Hardware Initialization */
  66         Joystick_Init();
  67         LEDs_Init();
  68         Buttons_Init();
  69         USB_Init();
  70 }
  71
  72 /** Event handler for the USB_Connect event. This indicates that the device is enumerating via the status LEDs. */
  73 void EVENT_USB_Connect(void)
  74 {
  75         /* Indicate USB enumerating */
  76         LEDs_SetAllLEDs(LEDMASK_USB_ENUMERATING);
  77 }
  78
  79 /** Event handler for the USB_Disconnect event. This indicates that the device is no longer connected to a host via
  80  *  the status LEDs, disables the sample update and PWM output timers and stops the USB and MIDI management tasks.
  81  */
  82 void EVENT_USB_Disconnect(void)
  83 {
  84         /* Indicate USB not ready */
  85         LEDs_SetAllLEDs(LEDMASK_USB_NOTREADY);
  86 }
  87
  88 /** Event handler for the USB_ConfigurationChanged event. This is fired when the host set the current configuration
  89  *  of the USB device after enumeration - the device endpoints are configured and the MIDI management task started.
  90  */
  91 void EVENT_USB_ConfigurationChanged(void)
  92 {
  93         /* Setup MIDI stream endpoints */
  94         Endpoint_ConfigureEndpoint(MIDI_STREAM_OUT_EPNUM, EP_TYPE_BULK,
  95                                        ENDPOINT_DIR_OUT, MIDI_STREAM_EPSIZE,
  96                                    ENDPOINT_BANK_SINGLE);
  97
  98         Endpoint_ConfigureEndpoint(MIDI_STREAM_IN_EPNUM, EP_TYPE_BULK,
  99                                        ENDPOINT_DIR_IN, MIDI_STREAM_EPSIZE,
 100                                    ENDPOINT_BANK_SINGLE);
 101
 102         /* Indicate USB connected and ready */
 103         LEDs_SetAllLEDs(LEDMASK_USB_READY);
 104 }
 105
 106 /** Task to handle the generation of MIDI note change events in response to presses of the board joystick, and send them
 107  *  to the host.
 108  */
 109 void MIDI_Task(void)
 110 {
 111         static uint8_t PrevJoystickStatus;
 112
 113         /* Select the MIDI IN stream */
 114         Endpoint_SelectEndpoint(MIDI_STREAM_IN_EPNUM);
 115
 116         /* Check if endpoint is ready to be written to */
 117         if (Endpoint_IsINReady())
 118         {
 119                 /* Get current joystick mask, XOR with previous to detect joystick changes */
 120                 uint8_t JoystickStatus  = Joystick_GetStatus();
 121                 uint8_t JoystickChanges = (JoystickStatus ^ PrevJoystickStatus);
 122
 123                 /* Get board button status - if pressed use channel 10 (percussion), otherwise use channel 1 */
 124                 uint8_t Channel = ((Buttons_GetStatus() & BUTTONS_BUTTON1) ? MIDI_CHANNEL(10) : MIDI_CHANNEL(1));
 125
 126                 if (JoystickChanges & JOY_LEFT)
 127                   SendMIDINoteChange(0x3C, (JoystickStatus & JOY_LEFT), 0, Channel);
 128
 129                 if (JoystickChanges & JOY_UP)
 130                   SendMIDINoteChange(0x3D, (JoystickStatus & JOY_UP), 0, Channel);
 131
 132                 if (JoystickChanges & JOY_RIGHT)
 133                   SendMIDINoteChange(0x3E, (JoystickStatus & JOY_RIGHT), 0, Channel);
 134
 135                 if (JoystickChanges & JOY_DOWN)
 136                   SendMIDINoteChange(0x3F, (JoystickStatus & JOY_DOWN), 0, Channel);
 137
 138                 if (JoystickChanges & JOY_PRESS)
 139                   SendMIDINoteChange(0x3B, (JoystickStatus & JOY_PRESS), 0, Channel);
 140
 141                 /* Save previous joystick value for next joystick change detection */
 142                 PrevJoystickStatus = JoystickStatus;
 143         }
 144
 145         /* Select the MIDI OUT stream */
 146         Endpoint_SelectEndpoint(MIDI_STREAM_OUT_EPNUM);
 147
 148         /* Check if endpoint is ready to be read from, if so discard its (unused) data */
 149         if (Endpoint_IsOUTReceived())
 150           Endpoint_ClearOUT();
 151 }
 152
 153 /** Sends a MIDI note change event (note on or off) to the MIDI output jack, on the given virtual cable ID and channel.
 154  *
 155  *  \param Pitch    Pitch of the note to turn on or off
 156  *  \param OnOff    Set to true if the note is on (being held down), or false otherwise
 157  *  \param CableID  ID of the virtual cable to send the note change to
 158  *  \param Channel  MIDI channel number to send the note change event to
 159  */
 160 void SendMIDINoteChange(const uint8_t Pitch, const bool OnOff, const uint8_t CableID, const uint8_t Channel)
 161 {
 162         /* Wait until endpoint ready for more data */
 163         while (!(Endpoint_IsReadWriteAllowed()));
 164
 165         /* Check if the message should be a Note On or Note Off command */
 166         uint8_t Command = ((OnOff)? MIDI_COMMAND_NOTE_ON : MIDI_COMMAND_NOTE_OFF);
 167
 168         /* Write the Packet Header to the endpoint */
 169         Endpoint_Write_Byte((CableID << 4) | (Command >> 4));
 170
 171         /* Write the Note On/Off command with the specified channel, pitch and velocity */
 172         Endpoint_Write_Byte(Command | Channel);
 173         Endpoint_Write_Byte(Pitch);
 174         Endpoint_Write_Byte(MIDI_STANDARD_VELOCITY);
 175
 176         /* Send the data in the endpoint to the host */
 177         Endpoint_ClearIN();
 178 }