The "synth fan a" uses LEDs to send frequencys to the LDRs and modulate these frequencys by fans that rotate inbetween them.
the SFa manual.
The synth fan small uses just the LDR and the fan to make sine wave like signals.
build on request: shop
// Synth Fan a // Gijs Gieskes june 2009 // Software version 16. byte ledA = 9; byte ledB = 10; boolean pinstate = LOW; //MIDI byte setNoteOn = 0x90; byte setNoteOff= 0x80; byte addMidiNote = 2; boolean but11 = false; int ampA = 0; byte ampAV = 0; boolean ampUD = false; byte volumeL1 = 0; //analog read values int av[] = {0,0,0,0}; //digitalread values boolean But[] = {0,0,0,0}; byte buts[] = {4,5,6,7,8}; //sequencer byte seq[3][257]; int seqCount = 1; boolean stepMode = true; byte FOrNoF[] = {0,0}; unsigned long timerA = 0; //clocks boolean clocksignals = false; //trigger out boolean triggerBool = LOW; byte triggerPin = 2; byte trigLedPin = 3; unsigned long intervalTime = 7000; unsigned int bins[] = {128, 64, 32, 16}; unsigned long anaV = 15208; unsigned int freq[] = {4049, 4290, 4545, 4815, 5102, 5405, 5727, 6067, 6428, 6810, 7215, 7644}; void setup() { //speed up PWM on pin 9 and 10: http://www.arduino.cc/cgi-bin/yabb2/YaBB.pl?num=1235060559 TCCR1B = TCCR1B & 0b11111000 | 0x01; for(int i=0; i<257; i++){ seq[0][i] = 255; seq[1][i] = 255; seq[2][i] = 255; } for(byte i=0; i<5; i++){ pinMode(buts[i], INPUT); digitalWrite(buts[i], HIGH); } pinMode(ledA, OUTPUT); pinMode(ledB, OUTPUT); pinMode(triggerPin, OUTPUT); pinMode(trigLedPin, OUTPUT); Serial.begin(31250); delay(200); } void loop() { if(micros() - timerA > intervalTime){ timerA = micros(); intervalTime = map(av[3], 0, 1023, 30000, 4000); //reading the potentiometers aread(); //reading the buttons dread(); //the sequencer seqRec(); //change sequencer step mode changeSettings(); midiNotes(); anaV = freq[(seq[0][seqCount] & B00001111) - 4] / bins[(seq[0][seqCount] >> 4) - 12]; FOrNoF[0] = seq[1][seqCount] & B00000001; FOrNoF[1] = seq[2][seqCount] & B00000001; //start stop sequence. StartStop(); //trigger clocking(); } if(clocksignals){ static byte delayCounter = 0; delayCounter++; if(delayCounter > 31){ delayCounter = 0; pinstate = !pinstate; if(pinstate && !FOrNoF[0]){ analogWrite(ledA, 0); }else{ analogWrite(ledA, ((seq[1][seqCount] >> 1) << 1)); } if(pinstate && !FOrNoF[1]){ analogWrite(ledB, 0); }else{ analogWrite(ledB, ((seq[2][seqCount] >> 1) << 1)); } } }else{ analogWrite(ledA, 0); analogWrite(ledB, 0); } delayMicroseconds(anaV-16); } void midiNotes(){ static byte lastNote = 0; static byte currNote = 0; currNote = ((7 - ((seq[0][seqCount] >> 4) - 11)) * 12) - ((seq[0][seqCount] & B00001111) - 4); currNote += 2 + addMidiNote; if(lastNote != currNote){ sendMIDI(setNoteOff, lastNote, 0); sendMIDI(setNoteOn, currNote, (seq[1][seqCount] >> 1)); lastNote = currNote; } } //http://itp.nyu.edu/physcomp/Labs/MIDIOutput void sendMIDI(char sb, char data1, char data2) { Serial.print(sb, BYTE); Serial.print(data1, BYTE); Serial.print(data2, BYTE); } void StartStop(){ static boolean SS = false; static boolean hold = false; if(But[0] == LOW){ hold = true; } if(But[0] == HIGH){ if(hold){ SS = !SS; if(SS){ //start sequence Serial.print(250, BYTE); clocksignals = true; }else{ //stop sequence Serial.print(252, BYTE); clocksignals = false; //reset the sequencers counter.. seqCount = 1; } hold = false; } } } void changeSettings(){ if(But[0] == LOW && But[1] == LOW){ stepMode = true; }else if(But[0] == LOW && But[2] == LOW){ stepMode = false; }else if(But[0] == LOW && But[3] == LOW){ addMidiNote = map(av[1], 0, 1023, 0, 3) * 12; //still needs correcting } } void clocking(){ static byte clockCounter = 0; clockCounter++; if(clockCounter > 3){ clockCounter = 0; //trigger signals if(clocksignals){ triggerBool = !triggerBool; digitalWrite(trigLedPin, triggerBool); digitalWrite(triggerPin, triggerBool); } //midi clock Serial.print(248, BYTE); Serial.print(248, BYTE); Serial.print(248, BYTE); } } void seqRec(){ if(clocksignals){ seqCount++; if(stepMode){ if(seqCount > map(av[0], 0, 1023, 1, 256)){ seqCount = 1; } }else{ if(seqCount > ((255 >> map(av[0], 0, 1023, 7, 0)) + 1)){ seqCount = 1; } } } if(But[1] == HIGH && But[4] == HIGH){ if(But[2] == LOW){ //record keyboard frequencys //octaves seq[0][seqCount] |= B11110000; seq[0][seqCount] &= ~(map(av[1], 0, 1023, 0, 3) << 4); //set firt bit in light seq LOW seq[1][seqCount] |= B00000001; seq[1][seqCount] &= B11111110; } if(But[3] == LOW){ //record keyboard frequencys //12 notes seq[0][seqCount] |= B00001111; seq[0][seqCount] &= ~map(av[2], 0, 1023, 0, 11); //set firt bit in light seq LOW seq[2][seqCount] |= B00000001; seq[2][seqCount] &= B11111110; } }else if(But[1] == LOW && But[4] == HIGH){ if(But[2] == LOW){ //volume A seq[1][seqCount] |= B11111110; //hide light seq bit. seq[1][seqCount] &= ~(map(av[1], 0, 1023, 127, 0) << 1); //shift 4 to left, inverse, merge. } if(But[3] == LOW){ //volume B seq[2][seqCount] |= B11111110; //hide light seq bit. seq[2][seqCount] &= ~(map(av[2], 0, 1023, 127, 0) << 1); } }else if(But[4] == LOW && But[1] == HIGH){ if(But[2] == LOW){ //set firts bit HIGH for light seq seq[1][seqCount] |= B00000001; seq[1][seqCount] &= B11111111; } if(But[3] == LOW){ //set firts bit HIGH for light seq seq[2][seqCount] |= B00000001; seq[2][seqCount] &= B11111111; } } } void aread(){ for(byte i=0; i<4; i++){ av[i] = analogRead(i); } } void dread(){ for(byte i=0; i<5; i++){ But[i] = digitalRead(buts[i]); } }
synth-fan-small
synth-fan-a
