Introduction
A knock sensor (as shown below) is similar to the shock switch except that it’s more sensitive. It can feel small amplitude vibration.
Components
– 1 * SunFounder Uno board
– 1 * USB data cable
– 1 * Knock sensor module
– Several jumper wires
Experimental Principle
The principle is similar to that of the shock switch. Connect the knock switch sensor pin S to D3 to build a simple circuit. When the knock switch sensor inducts knock signals, the LED attached to pin 13 will light up.
Experimental Procedures
Step 1: Build the circuit
Knock Sensor Module SunFounder Uno
S —————————————-D3
– ————————————- GND
+ ————————————— 5V
Step 2: Program (Please refer to the example code in LEARN -> Get Tutorial on our website)
Step 3: Compile
Step 4: Upload the sketch to SunFounder Uno
Now, knock the sensor and the LED attached to pin 13 on the SunFounder Uno board will light up.
C Code
const int knockPin = 3; // the number of the knock sensor pin const int ledPin = 13; // the number of the LED pin// variables will change: int buttonState = 0; // variable for reading the knock sensor statusvoid setup() { // initialize the LED pin as an output: pinMode(ledPin, OUTPUT); // initialize the knock sensor pin as an input: pinMode(knockPin, INPUT); }void loop(){ // read the state of the knock sensor value: buttonState = digitalRead(knockPin);// check if the knock sensor is pressed. // if it is, the knock sensor is HIGH: if (buttonState == HIGH) { // turn LED on: digitalWrite(ledPin, LOW); } else { // turn LED off: digitalWrite(ledPin, HIGH); } } |