Hello everyone,
I'm very new to all electronic and programming stuff. Bought my Arduino few weeks ago and just been playing around.
I want to make secret clapping switch. For that I used this code that I have found online. But there is a problem. When I connect this microphone to input pin it start to give me non stop signal. Eaven when i take the mic out it continues to pick up some signal. I suppose the problem is in a code but just cannot find it.
Tried messing with the threshold. I made more simple clapper with this mic and it worked so I guess it's ok.
Thank you for your help.
/*
By Steve Hoefer http://grathio.com
Version 0.1.10.20.10
Licensed under Creative Commons Attribution-Noncommercial-Share Alike 3.0
http://creativecommons.org/licenses/by-nc-sa/3.0/us/
(In short: Do what you want, just be sure to include this line and the four above it, and don't sell it or use it in anything you sell without contacting me.)
*/
const int knockSensor = 2; // Piezo sensor on pin 0.
const int programSwitch = 2; // If this is high we program a new code.
const int lockMotor = 3; // Gear motor used to turn the lock.
const int redLED = 4; // Status LED
const int greenLED = 5; // Status LED
const int threshold = 15;
const int rejectValue = 25;
const int averageRejectValue = 15;
const int knockFadeTime = 150; // milliseconds we allow a knock to fade before we listen for another one. (Debounce timer.)
const int lockTurnTime = 2000; /
const int maximumKnocks = 20; // Maximum number of knocks to listen for.
const int knockComplete = 1200; /
int secretCode[maximumKnocks] = {50, 25, 25, 50, 100, 50, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}; // Initial setup: "Shave and a Hair Cut, two bits."
int knockReadings[maximumKnocks]; // When someone knocks this array fills with delays between knocks.
int knockSensorValue = 0; // Last reading of the knock sensor.
int programButtonPressed = false; // Flag so we remember the programming button setting at the end of the cycle.
void setup() {
pinMode(lockMotor, OUTPUT);
pinMode(redLED, OUTPUT);
pinMode(greenLED, OUTPUT);
pinMode(programSwitch, INPUT);
Serial.begin(9600); // Uncomment the Serial.bla lines for debugging.
Serial.println("Program start.");
digitalWrite(greenLED, HIGH);
}
void loop() {
// Listen for any knock at all.
knockSensorValue = analogRead(knockSensor);
if (digitalRead(programSwitch)==HIGH){ // is the program button pressed?
programButtonPressed = true; // Yes, so lets save that state
digitalWrite(redLED, HIGH); // and turn on the red light too so we know we're programming.
} else {
programButtonPressed = false;
digitalWrite(redLED, LOW);
}
if (knockSensorValue >=threshold){
listenToSecretKnock();
}
}
// Records the timing of knocks.
void listenToSecretKnock(){
Serial.println("knock starting");
int i = 0;
// First lets reset the listening array.
for (i=0;i<maximumKnocks;i++){
knockReadings[i]=0;
}
int currentKnockNumber=0; // Incrementer for the array.
int startTime=millis();
int now=millis();
digitalWrite(greenLED, LOW);
if (programButtonPressed==true){
digitalWrite(redLED, LOW);
}
delay(knockFadeTime);
digitalWrite(greenLED, HIGH);
if (programButtonPressed==true){
digitalWrite(redLED, HIGH);
}
do {
//listen for the next knock or wait for it to timeout.
knockSensorValue = analogRead(knockSensor);
if (knockSensorValue >=threshold){ //got another knock...
//record the delay time.
Serial.println("knock.");
now=millis();
knockReadings[currentKnockNumber] = now-startTime;
currentKnockNumber ++; //increment the counter
startTime=now;
// and reset our timer for the next knock
digitalWrite(greenLED, LOW);
if (programButtonPressed==true){
digitalWrite(redLED, LOW); // and the red one too if we're programming a new knock.
}
delay(knockFadeTime); // again, a little delay to let the knock decay.
digitalWrite(greenLED, HIGH);
if (programButtonPressed==true){
digitalWrite(redLED, HIGH);
}
}
now=millis();
//did we timeout or run out of knocks?
} while ((now-startTime < knockComplete) && (currentKnockNumber < maximumKnocks));
//we've got our knock recorded, lets see if it's valid
if (programButtonPressed==false){ // only if we're not in progrmaing mode.
if (validateKnock() == true){
triggerDoorUnlock();
} else {
Serial.println("Secret knock failed.");
digitalWrite(greenLED, LOW); // We didn't unlock, so blink the red LED as visual feedback.
for (i=0;i<4;i++){
digitalWrite(redLED, HIGH);
delay(100);
digitalWrite(redLED, LOW);
delay(100);
}
digitalWrite(greenLED, HIGH);
}
} else { // if we're in programming mode we still validate the lock, we just don't do anything with the lock
validateKnock();
// and we blink the green and red alternately to show that program is complete.
Serial.println("New lock stored.");
digitalWrite(redLED, LOW);
digitalWrite(greenLED, HIGH);
for (i=0;i<3;i++){
delay(100);
digitalWrite(redLED, HIGH);
digitalWrite(greenLED, LOW);
delay(100);
digitalWrite(redLED, LOW);
digitalWrite(greenLED, HIGH);
}
}
}
// Runs the motor (or whatever) to unlock the door.
void triggerDoorUnlock(){
Serial.println("Door unlocked!");
int i=0;
// turn the motor on for a bit.
digitalWrite(lockMotor, HIGH);
digitalWrite(greenLED, HIGH); // And the green LED too.
delay (lockTurnTime); // Wait a bit.
digitalWrite(lockMotor, LOW); // Turn the motor off.
// Blink the green LED a few times for more visual feedback.
for (i=0; i < 5; i++){
digitalWrite(greenLED, LOW);
delay(100);
digitalWrite(greenLED, HIGH);
delay(100);
}
}
// Sees if our knock matches the secret.
// returns true if it's a good knock, false if it's not.
// todo: break it into smaller functions for readability.
boolean validateKnock(){
int i=0;
int currentKnockCount = 0;
int secretKnockCount = 0;
int maxKnockInterval = 0; // We use this later to normalize the times.
for (i=0;i<maximumKnocks;i++){
if (knockReadings[i] > 0){
currentKnockCount++;
}
if (secretCode[i] > 0){ //todo: precalculate this.
secretKnockCount++;
}
if (knockReadings[i] > maxKnockInterval){ // collect normalization data while we're looping.
maxKnockInterval = knockReadings[i];
}
}
// If we're recording a new knock, save the info and get out of here.
if (programButtonPressed==true){
for (i=0;i<maximumKnocks;i++){ // normalize the times
secretCode[i]= map(knockReadings[i],0, maxKnockInterval, 0, 100);
}
digitalWrite(greenLED, LOW);
digitalWrite(redLED, LOW);
delay(1000);
digitalWrite(greenLED, HIGH);
digitalWrite(redLED, HIGH);
delay(50);
for (i = 0; i < maximumKnocks ; i++){
digitalWrite(greenLED, LOW);
digitalWrite(redLED, LOW);
// only turn it on if there's a delay
if (secretCode[i] > 0){
delay( map(secretCode[i],0, 100, 0, maxKnockInterval));
digitalWrite(greenLED, HIGH);
digitalWrite(redLED, HIGH);
}
delay(50);
}
return false;
}
if (currentKnockCount != secretKnockCount){
return false;
}
int totaltimeDifferences=0;
int timeDiff=0;
for (i=0;i<maximumKnocks;i++){
knockReadings[i]= map(knockReadings[i],0, maxKnockInterval, 0, 100);
timeDiff = abs(knockReadings[i]-secretCode[i]);
if (timeDiff > rejectValue){
return false;
}
totaltimeDifferences += timeDiff;
}
if (totaltimeDifferences/secretKnockCount>averageRejectValue){
return false;
}
return true;
}