Chris Taylor
Music Engine plays Music Macro Language compositions in the background
Dependents: RETRO_BallsAndPaddle RETRO_BallAndHoles MusicBoxForFathersDay USBSec_mbed-os_dev
Music Engine is a simply library to execute Music Macro Language sequences asynchronously. Learn more about MML on wikipedia http://en.wikipedia.org/wiki/Music_Macro_Language
The following sample plays a simple tune
#include "mbed.h"
#include "MusicEngine.h"
// Play music on MCU Pin 0.18
// The pin should support PWM
MusicEngine music(P0_18);
main()
{
music.play("T224L8O5CL16>C<P16GP16L8EL16P16>C<GP16L8E.L16P16L8C#L16>C#<P16G#P16L8FL16P16>C#<G#P16L8F.L16P16L8CL16>C<P16GP16L8EL16P16>C<GP16L8E.L16P16D#EFP16FF#GP16GG#AP16L8>C<P8L4>C");
while(1)
{
}
}
Diff: MusicEngine.cpp
- Revision:
- 0:d873d5d62d3b
- Child:
- 2:4f7c4255997a
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/MusicEngine.cpp Thu Feb 05 04:18:39 2015 +0000
@@ -0,0 +1,215 @@
+///////////////////////////////////////////////////////////////////////////////
+// Retro Music Engine
+// Author: Chris Taylor (taylorza)
+
+#include "MusicEngine.h"
+#include <cctype>
+
+const float MusicEngine::WHOLE_NOTE_DURATION = 1.0f;
+const float MusicEngine::QUARTER_NOTE_DURATION = MusicEngine::WHOLE_NOTE_DURATION / 4.0f;
+const float MusicEngine::QUARTER_NOTES_PER_MINUTE = 60.0f / MusicEngine::QUARTER_NOTE_DURATION;
+
+const float MusicEngine::DEFAULT_TIMING = 7.0f / 8.0f;
+const float MusicEngine::LEGATO_TIMING = 1.0f;
+const float MusicEngine::STACCATO_TIMING = 3.0f / 4.0f;
+
+const int MusicEngine::NOTE_REST = 0;
+const int MusicEngine::NOTE_C = 1;
+const int MusicEngine::NOTE_CS = 2;
+const int MusicEngine::NOTE_D = 3;
+const int MusicEngine::NOTE_DS = 4;
+const int MusicEngine::NOTE_E = 5;
+const int MusicEngine::NOTE_F = 6;
+const int MusicEngine::NOTE_FS = 7;
+const int MusicEngine::NOTE_G = 8;
+const int MusicEngine::NOTE_GS = 9;
+const int MusicEngine::NOTE_A = 10;
+const int MusicEngine::NOTE_AS = 11;
+const int MusicEngine::NOTE_B = 12;
+
+MusicEngine::MusicEngine(PinName pin) :
+ _pwm(pin),
+ _isPlaying(false)
+{
+ _pwm = 0.0f;
+ _pwm.period(0);
+}
+
+void MusicEngine::play(char *mml)
+{
+ __disable_irq();
+ _isPlaying = false;
+ _mml = mml;
+ _mmlIndex = 0;
+ _octave = 4;
+ _duration = QUARTER_NOTE_DURATION;
+ _durationRatio = DEFAULT_TIMING;
+ _tempo = 120;
+ _pwm.period(0);
+ _pwm = 0.5f;
+ _pause = 0;
+ _isPlaying = true;
+ __enable_irq();
+
+ MusicEngine::executeCommand();
+}
+
+void MusicEngine::stop()
+{
+ __disable_irq();
+ _isPlaying = false;
+ __enable_irq();
+}
+
+void MusicEngine::executeCommand()
+{
+ if (_pause != 0)
+ {
+ _pwm.period(0);
+ _pwm = 0.0f;
+ _scheduler.attach(this, &MusicEngine::executeCommand, _pause);
+ _pause = 0;
+ }
+ else
+ {
+ int freqIndex = -1;
+ do
+ {
+ skipWhiteSpace();
+ switch(getChar())
+ {
+ case 'a': freqIndex = NOTE_A; break;
+ case 'b': freqIndex = NOTE_B; break;
+ case 'c': freqIndex = NOTE_C; break;
+ case 'd': freqIndex = NOTE_D; break;
+ case 'e': freqIndex = NOTE_E; break;
+ case 'f': freqIndex = NOTE_F; break;
+ case 'g': freqIndex = NOTE_G; break;
+
+ case 'p':
+ case 'r': freqIndex = NOTE_REST; break;
+
+ case 'l': if (isdigit(peekChar())) _duration = (float)WHOLE_NOTE_DURATION / getNumber(1, 64); break;
+ case 'o': if (isdigit(peekChar())) _octave = getNumber(0, 7); break;
+ case 't': if (isdigit(peekChar())) _tempo = getNumber(32, 255); break;
+ case 'm':
+ switch(getChar())
+ {
+ case 'n': _durationRatio = DEFAULT_TIMING; break;
+ case 'l': _durationRatio = LEGATO_TIMING; break;
+ case 's': _durationRatio = STACCATO_TIMING; break;
+ }
+ break;
+
+ case 'n': if (isdigit(peekChar())) freqIndex = getNumber(0, 96); break;
+ case '<': --_octave; if (_octave < 0) _octave = 0; break;
+ case '>': ++_octave; if (_octave > 7) _octave = 7; break;
+
+ case '\0':
+ _isPlaying = false;
+ break;
+ }
+
+ if (!_isPlaying)
+ {
+ _pwm = 0.0;
+ _pwm.period(0);
+ _completionCallback.call();
+ return;
+ }
+
+ float durationRatio = _durationRatio;
+ float duration = _duration;
+
+ if (freqIndex != -1)
+ {
+ switch(getChar())
+ {
+ case '+':
+ case '#': ++freqIndex; break;
+
+ case '-': --freqIndex; break;
+ case '.':
+ durationRatio = 3.0f / 2.0f;
+ while(peekChar() == '.')
+ {
+ durationRatio *= 3.0f / 2.0f;
+ getChar();
+ }
+ break;
+ default:
+ rewind();
+ break;
+ }
+
+ if (isdigit(peekChar()))
+ {
+ duration = WHOLE_NOTE_DURATION / getNumber(1, 64);
+ }
+
+ if (freqIndex != NOTE_REST)
+ {
+ _pwm.period(PERIOD_TABLE[freqIndex + (_octave * 12)]);
+ _pwm = 0.5;
+ }
+
+ duration *= (QUARTER_NOTES_PER_MINUTE / _tempo);
+ _scheduler.attach(this, &MusicEngine::executeCommand, duration * durationRatio);
+ _pause = duration * (1 - durationRatio);
+ }
+ } while (freqIndex == -1);
+ }
+}
+
+int MusicEngine::getNumber(int min, int max)
+{
+ char ch;
+ int value = 0;
+ while ((ch = getChar()) != 0)
+ {
+ if (!isdigit(ch))
+ {
+ rewind();
+ break;
+ }
+ int digit = (int)ch - 48;
+ value = (value * 10) + digit;
+ }
+ value = value < min ? min : value > max ? max : value;
+ return value;
+}
+
+void MusicEngine::skipWhiteSpace()
+{
+ while (isspace(peekChar())) getChar();
+}
+
+char MusicEngine::getChar()
+{
+ return tolower(_mml[_mmlIndex++]);
+}
+
+char MusicEngine::peekChar()
+{
+ return tolower(_mml[_mmlIndex]);
+}
+
+void MusicEngine::rewind()
+{
+ --_mmlIndex;
+}
+
+const float MusicEngine::PERIOD_TABLE[] =
+{
+ 0,
+ //1 2 3 4 5 6 7 8 9 10 11 12
+ //C C# D D# E F F# G G# A A# B
+ 1.0f / 16.35f, 1.0f / 17.32f, 1.0f / 18.35f, 1.0f / 19.45f, 1.0f / 20.60f, 1.0f / 21.83f, 1.0f / 23.12f, 1.0f / 24.50f, 1.0f / 25.96f, 1.0f / 27.50f, 1.0f / 29.14f, 1.0f / 30.87f, // Octave 0
+ 1.0f / 32.70f, 1.0f / 34.65f, 1.0f / 36.71f, 1.0f / 38.89f, 1.0f / 41.20f, 1.0f / 43.65f, 1.0f / 46.25f, 1.0f / 49.00f, 1.0f / 51.91f, 1.0f / 55.00f, 1.0f / 58.27f, 1.0f / 61.74f, // Octave 1
+ 1.0f / 65.41f, 1.0f / 69.30f, 1.0f / 73.42f, 1.0f / 77.78f, 1.0f / 82.41f, 1.0f / 87.31f, 1.0f / 92.50f, 1.0f / 98.00f, 1.0f / 103.83f, 1.0f / 110.00f, 1.0f / 116.54f, 1.0f / 123.47f, // Octave 2
+ 1.0f / 130.81f, 1.0f / 138.59f, 1.0f / 146.83f, 1.0f / 155.56f, 1.0f / 164.81f, 1.0f / 174.62f, 1.0f / 185.00f, 1.0f / 196.00f, 1.0f / 207.65f, 1.0f / 220.00f, 1.0f / 233.08f, 1.0f / 246.94f, // Octave 3
+ 1.0f / 261.63f, 1.0f / 277.18f, 1.0f / 293.67f, 1.0f / 311.13f, 1.0f / 329.63f, 1.0f / 349.23f, 1.0f / 370.00f, 1.0f / 392.00f, 1.0f / 415.31f, 1.0f / 440.00f, 1.0f / 466.17f, 1.0f / 493.89f, // Octave 4
+ 1.0f / 523.25f, 1.0f / 554.37f, 1.0f / 587.33f, 1.0f / 622.26f, 1.0f / 659.26f, 1.0f / 698.46f, 1.0f / 739.99f, 1.0f / 783.99f, 1.0f / 830.61f, 1.0f / 880.00f, 1.0f / 932.33f, 1.0f / 987.77f, // Octave 5
+ 1.0f / 1046.51f, 1.0f / 1108.74f, 1.0f / 1174.67f, 1.0f / 1244.51f, 1.0f / 1318.52f, 1.0f / 1396.92f, 1.0f / 1479.99f, 1.0f / 1567.99f, 1.0f / 1661.23f, 1.0f / 1760.01f, 1.0f / 1864.66f, 1.0f / 1975.54f, // Octave 6
+ 1.0f / 2093.02f, 1.0f / 2217.47f, 1.0f / 2349.33f, 1.0f / 2489.03f, 1.0f / 2637.03f, 1.0f / 2793.84f, 1.0f / 2959.97f, 1.0f / 3135.98f, 1.0f / 3322.45f, 1.0f / 3520.02f, 1.0f / 3729.33f, 1.0f / 3951.09f, // Octave 7
+};
\ No newline at end of file