Knock - a // these variables will change: int sensorReading...

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/* Knock Sensor This sketch reads a piezo element to detect a knocking sound. It reads an analog pin and compares the result to a set threshold. If the result is greater than the threshold, it writes "knock" to the serial port, and toggles the LED on pin 13. The circuit: * + connection of the piezo attached to analog in 0 * - connection of the piezo attached to ground * 1-megohm resistor attached from analog in 0 to ground * created 25 Mar 2007 by David Cuartielles <> modified 4 Sep 2010 by Tom Igoe This example code is in the public domain. */ // these constants won't change: const int ledPin = 13; // led connected to digital pin 13 const int knockSensor = A0; // the piezo is connected to analog pin 0 const int threshold = 100; // threshold value to decide when the detected sound is a knock or not
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Unformatted text preview: a // these variables will change: int sensorReading = 0; // variable to store the value read from the sensor pin int ledState = LOW; // variable used to store the last LED status, to toggle the light t void setup() { pinMode(ledPin, OUTPUT); // declare the ledPin as as OUTPUT Serial.begin(9600); // use the serial port } void loop() { // read the sensor and store it in the variable sensorReading: sensorReading = analogRead(knockSensor); // if the sensor reading is greater than the threshold: if (sensorReading >= threshold) { // toggle the status of the ledPin: ledState = !ledState; // update the LED pin itself: digitalWrite(ledPin, ledState); // send the string "Knock!" back to the computer, followed by newline Serial.println("Knock!"); } delay(100); // delay to avoid overloading the serial port buffer }...
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This note was uploaded on 01/31/2011 for the course CS 302 taught by Professor J.parker during the Spring '08 term at University of Texas.

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