Creating a buzzer alarm when accelometer ( ADXL 335 )is moved by someone.

Hi, I am trying to make an alarm by buzzer whenever accelometer ADXL335 moves. I am using arduino UNO … connections are done, but the problem is in code as I have no background… . i tried to merge the buzzer code and the ADXL 335 code and put a condition if ( Xval >= 50 || Yval <= 50 | Zval <= 50 ) , buzzer shall alarm on … there is an error in the code but i dot know what is it… please help :slight_smile: :


Reads an Analog Devices ADXL3xx accelerometer and communicates the
acceleration to the computer. The pins used are designed to be easily
compatible with the breakout boards from SparkFun, available from:

The circuit:

  • analog 0: accelerometer self test
  • analog 1: z-axis
  • analog 2: y-axis
  • analog 3: x-axis
  • analog 4: ground
  • analog 5: vcc

created 2 Jul 2008
by David A. Mellis
modified 30 Aug 2011
by Tom Igoe

This example code is in the public domain.


// these constants describe the pins. They won’t change:
const int groundpin = 18; // analog input pin 4 – ground
const int powerpin = 19; // analog input pin 5 – voltage
const int xpin = A3; // x-axis of the accelerometer
const int ypin = A2; // y-axis
const int zpin = A1; // z-axis (only on 3-axis models)

void setup() {
// initialize the serial communications:

// Provide ground and power by using the analog inputs as normal digital pins.
// This makes it possible to directly connect the breakout board to the
// Arduino. If you use the normal 5V and GND pins on the Arduino,
// you can remove these lines.
pinMode(groundpin, OUTPUT);
pinMode(powerpin, OUTPUT);
digitalWrite(groundpin, LOW);
digitalWrite(powerpin, HIGH);

// For Buzzer.
pinMode(buzzer, OUTPUT); // Set buzzer - pin 9 as an output

void loop() {
// print the sensor values:
// print a tab between values:
// print a tab between values:
// delay before next reading:

// For Buzzer
if ( Xval >= 50 || Yval <= 50 | Zval <= 50 ) {
tone(buzzer, 1000); // Send 1KHz sound signal…
delay(100); // …for 1 sec
noTone(buzzer); // Stop sound…
delay(100); // …for 1sec

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