/*
Microphone Light On/Off Example
This is an example that show how a light can be turned on and off by a high sound.
The light stays in its state unil a new high sound arrives.
Circuit
- Electret microphone
- 220 ohm resistor
- LED
Created by Inge Edward Halsaunet, 2015
Released into the public domain
*/
const int micIn = 2; // Digital pin the microphone is connected to
const int ledOut = 3; // Digital pin the led is connected to
int previousSensorReading = 0; // Remember the previous reading of our microphone
int state = LOW; // Current led state (HIGH or LOW)
void setup() {
// Start serial communication with console
Serial.begin(9600);
// Initialize inputs and outputs
pinMode(micIn, INPUT);
pinMode(ledOut, OUTPUT);
}
void loop() {
// Read the current microphone level
int sensorRead = digitalRead(micIn);
// See if reading has changed since last time
if (previousSensorReading != sensorRead) {
// Remember to update previous reading
previousSensorReading = sensorRead;
Serial.print("Changed, now: ");
// When senosor is in high state, only notify user.
if (sensorRead == HIGH) {
Serial.println("High");
} else {
// When sensor changes to low state, we change the state of our output light.
// This prevents the light from just giva a short flash, but instead remain on or off.
Serial.println("Low");
if (state == HIGH) {
state = LOW;
} else {
state = HIGH;
}
}
}
// Update output light value
digitalWrite(ledOut, state);
// Short delay to ensure sensor stability
delay(1);
} | 