View source for ADXL345 Triple Axis Accelerometer Breakout

==Introduction==
[[File:ADXL345 1.jpg|250px]]

This is a breakout board for Analog Devices ADXL345 3-Axis Accelerometer.The ADXL345 is a small, thin, ultralow power, 3-axis accelerometer with high resolution (13-bit) measurement at up to ±16 g. Digital output data is formatted as 16-bit twos complement and is accessible through either a SPI (3- or 4-wire) or I2C digital interface. The ADXL345 is well suited for mobile device applications. It measures the 
static acceleration of gravity in tilt-sensing applications, as well as dynamic acceleration resulting from motion or shock. Its high resolution (3.9 mg/LSB) enables measurement of inclination changes less than 1.0°.

==Features==
*Ultralow power: as low as 23 μA in measurement mode
*Fixed 10-bit resolution Full resolution, up to 13-bit resolution at ±16 g 
*Single tap/double tap detection
*Activity/inactivity monitoring
*Free-fall detection
*Supply voltage range: 2.0 V to 3.6 V 
*I/O voltage range: 1.7 V to VS
*SPI (3- and 4-wire) and I2C digital interfaces 

==Document==
[http://www.geeetech.com/Documents/ADXL345%20Datasheet.pdf ADXL345 Datasheet]

==Usage==
Here is the guide illustrates how to connect an Arduino to the ADXL335 breakout board. The following is a table describing which pins on the 
Arduino should be connected to the pins on the accelerometer: 

[[File:345 wiring1.jpg|500px]]
[[File:ADX table.jpg]]

==Example code==
 #include <Wire.h> // I2C library, gyroscope
 // Accelerometer ADXL345
 #define ACC (0xA7>>1)    //ADXL345 ACC address
 #define A_TO_READ (6)        //num of bytes we are going to read each time (two bytes for each axis)
 void initAcc() {
  //Turning on the ADXL345
  writeTo(ACC, 0x2D, 1<<3);      
  writeTo(ACC, 0x31, 0x0B);
  writeTo(ACC, 0x2C, 0x09);
  //by default the device is in +-2g range reading
 }
 void getAccelerometerData(int * result) {
  int regAddress = 0x32;    //first axis-acceleration-data register on the ADXL345
  byte buff[A_TO_READ];
  readFrom(ACC, regAddress, A_TO_READ, buff); //read the acceleration data from the ADXL345
  //each axis reading comes in 10 bit resolution, ie 2 bytes.  Least Significat Byte first!!
  //thus we are converting both bytes in to one int
  result[0] = (((int)buff[1]) << 8) | buff[0];   
  result[1] = (((int)buff[3])<< 8) | buff[2];
  result[2] = (((int)buff[5]) << 8) | buff[4];
 }
 void setup()
 {
  Serial.begin(9600);
  Wire.begin();
  initAcc();
 }
 void loop()
 {
 int hx,hy,hz;
 int acc[3];
 getAccelerometerData(acc);
 hx = acc[0];
 hy = acc[1];
 hz = acc[2];
 Serial.print(" X=");
 Serial.print(hx);
 Serial.print(" Y=");
 Serial.print(hy);
 Serial.print(" Z=");
 Serial.println(hz);
 delay(50); 
 }
 //---------------- Functions
 //Writes val to address register on ACC
 void writeTo(int DEVICE, byte address, byte val) {
   Wire.beginTransmission(DEVICE); //start transmission to ACC 
   Wire.send(address);        // send register address
   Wire.send(val);        // send value to write
   Wire.endTransmission(); //end transmission
 }
 //reads num bytes starting from address register on ACC in to buff array
  void readFrom(int DEVICE, byte address, int num, byte buff[]) {
  Wire.beginTransmission(DEVICE); //start transmission to ACC 
  Wire.send(address);        //sends address to read from
  Wire.endTransmission(); //end transmission
  
  Wire.beginTransmission(DEVICE); //start transmission to ACC
  Wire.requestFrom(DEVICE, num);    // request 6 bytes from ACC
  int i = 0;
  while(Wire.available())    //ACC may send less than requested (abnormal)
  { 
    buff[i] = Wire.receive(); // receive a byte
    i++;
  }
  Wire.endTransmission(); //end transmission
 }

==How to buy==
Click here to buy [http://www.geeetech.com/adxl345triple-axis-accelerometer-breakout-p-384.html ADXL345 3-Axis Accelerometer Breakout]