^the harp is upside-down so I can mess with the photo-resistors

here's the code 1 of 2:

/*

MIDI-enabled Laser Harp
SOURCE: http://open-source-energy.org/?topic=1129.0

See: MIDI Technical Specifications
http://en.wikipedia.org/wiki/MIDI#Technical_specifications

*/

#define MIDI_LASER_COUNT 9
#define MIDI_LASER_OCTAVE_DOWN 0
#define MIDI_LASER_OCTAVE_UP 8

short midiCalibrateAmbientLight = 1023;
boolean midiLaserState[MIDI_LASER_COUNT] = {false, false, false, false, false, false, false, false, false};
byte midiNotes[MIDI_LASER_COUNT] = {0, 0, 2, 4, 5, 7, 9, 11, 0};
byte midiOctave = 5;
byte midiPinLaser[MIDI_LASER_COUNT] = {3, 4, 5, 6, 7, 8, 9, 10, 11};
byte midiPinVelocity = A0;
unsigned long midiRateLimit[MIDI_LASER_COUNT] = {0, 0, 0, 0, 0, 0, 0, 0, 0};
unsigned long midiRateLimitThreshold = 35;
unsigned long midiRateLimitThresholdOctave = 70;
byte midiVelocity = 127;

void setup() {
calibrateAmbientLight();
midiInitSerial();
midiInitPins();
midiIntroSong();
}

part 2 of 3 cont:

void loop() {
midiReadLasers();
midiReadVelocity();
}

void calibrateAmbientLight() {
delay(100);
midiCalibrateAmbientLight = analogRead(midiPinVelocity);
}

void midiIntroSong() {
delay(1);
midiSendNoteOn(60, 127);
delay(125);
midiSendNoteOff(60);
midiSendNoteOn(64, 127);
delay(125);
midiSendNoteOff(64);
midiSendNoteOn(67, 127);
delay(125);
midiSendNoteOff(67);
midiSendNoteOn(72, 127);
delay(250);
midiSendNoteOff(72);
midiSendNoteOn(67, 127);
delay(125);
midiSendNoteOff(67);
midiSendNoteOn(72, 127);
delay(500);
midiSendNoteOff(72);
}

boolean midiHandleOctave(byte thePin, boolean theState) {
if (!theState) {return false;}
if ((thePin == MIDI_LASER_OCTAVE_DOWN) && midiOctave == 0) {return false;}
if ((thePin == MIDI_LASER_OCTAVE_UP) && midiOctave == 9) {return false;}
midiOctaveKill();
switch(thePin) {
case MIDI_LASER_OCTAVE_DOWN:
midiOctave--;
break;
case MIDI_LASER_OCTAVE_UP:
midiOctave++;
break;
}
return true;
}

boolean midiHandleRateLimit(byte thePin) {
unsigned long theMillis = millis();
unsigned long theThreshold = 0;
switch (thePin) {
case MIDI_LASER_OCTAVE_DOWN:
case MIDI_LASER_OCTAVE_UP:
theThreshold = midiRateLimitThresholdOctave;
break;
default:
theThreshold = midiRateLimitThreshold;
break;
}
if (theMillis - midiRateLimit[thePin] >= theThreshold) {
midiRateLimit[thePin] = theMillis;
return true;
}
return false;
}

part 3 of 3:

void midiHandleReadLaser(byte thePin, boolean theState) {
if ((midiLaserState[thePin] != theState) && midiHandleRateLimit(thePin)) {
midiLaserState[thePin] = theState;
if ((thePin == MIDI_LASER_OCTAVE_DOWN) || (thePin == MIDI_LASER_OCTAVE_UP)) {
midiHandleOctave(thePin, theState);
} else if (theState) {
midiSendNoteOn(midiNotes[thePin] + (12 *midiOctave), midiVelocity);
} else {
midiSendNoteOff(midiNotes[thePin] + (12 *midiOctave));
}
}
}

void midiInitPins() {
for (byte thePin = 0; thePin < MIDI_LASER_COUNT; thePin++) {
pinMode(midiPinLaser[thePin], INPUT);
}
}

void midiInitSerial() {
Serial.begin(31250);
}

void midiOctaveKill() {
for (byte thePin = 0; thePin < MIDI_LASER_COUNT; thePin++) {
if ((thePin == MIDI_LASER_OCTAVE_DOWN) || (thePin == MIDI_LASER_OCTAVE_UP)) {continue;}
midiHandleReadLaser(thePin, LOW);
}
}

void midiReadLasers() {
for (byte thePin = 0; thePin < MIDI_LASER_COUNT; thePin++) {
midiHandleReadLaser(thePin, digitalRead(midiPinLaser[thePin]));
}
}

void midiReadVelocity() {
midiVelocity = map(analogRead(midiPinVelocity), 0, midiCalibrateAmbientLight, 1, 127);
}

void midiSendCC(byte theCC, byte theValue) {
Serial.write(B10110000);
Serial.write(theCC);
Serial.write(theValue);
}

void midiSendNoteOff(byte theNote) {
Serial.write(B10000000);
Serial.write(theNote);
Serial.write(0);
delay(1);
}

void midiSendNoteOn(byte theNote, byte theVelocity) {
Serial.write(B10010000);
Serial.write(theNote);
Serial.write(theVelocity);
delay(1);
}

>>917291
i dont into programming but reading the code
>byte midiOctave = 5;
maybe but just test and tune altering
other alternative
contact the programmer and ask the source directly