exploringBB::ADXL345 Class Reference

Specific class for the ADXL345 Accelerometer. More...

#include <ADXL345.h>

Public Types
enum	RANGE { PLUSMINUS_2_G = 0, PLUSMINUS_4_G = 1, PLUSMINUS_8_G = 2, PLUSMINUS_16_G = 3 }
	An enumeration to define the gravity range of the sensor. More...
enum	RESOLUTION { NORMAL = 0, HIGH = 1 }
	The resolution of the sensor. High is only available in +/- 16g range. More...

Public Member Functions
	ADXL345 (BusDevice *busDevice)
virtual int	readSensorState ()
virtual void	setRange (ADXL345::RANGE range)
virtual ADXL345::RANGE	getRange ()
virtual void	setResolution (ADXL345::RESOLUTION resolution)
virtual ADXL345::RESOLUTION	getResolution ()
virtual short	getAccelerationX ()
virtual short	getAccelerationY ()
virtual short	getAccelerationZ ()
virtual float	getPitch ()
virtual float	getRoll ()
virtual void	displayPitchAndRoll (int iterations=600)
virtual	~ADXL345 ()

Detailed Description

Specific class for the ADXL345 Accelerometer.

Member Enumeration Documentation

enum exploringBB::ADXL345::RANGE

An enumeration to define the gravity range of the sensor.

Enumerator
PLUSMINUS_2_G	plus/minus 2g
PLUSMINUS_4_G	plus/minus 4g
PLUSMINUS_8_G	plus/minus 8g
PLUSMINUS_16_G	plus/minus 16g

                   {
                PLUSMINUS_2_G           = 0,
                PLUSMINUS_4_G           = 1,
                PLUSMINUS_8_G           = 2,
                PLUSMINUS_16_G          = 3 
        };

enum exploringBB::ADXL345::RESOLUTION

The resolution of the sensor. High is only available in +/- 16g range.

Enumerator
NORMAL	NORMAL 10-bit resolution.
HIGH	HIGH 13-bit resolution.

                        {
                NORMAL = 0,
                HIGH = 1   
        };

Constructor & Destructor Documentation

exploringBB::ADXL345::ADXL345

(

BusDevice *

busDevice

)

The constructor for the ADXL345 accelerometer object. It passes the bus number and the device address (with is 0x53 by default) to the constructor of I2CDevice. All of the states are initialized and the registers are updated.

Parameters

I2CBus	The bus number that the ADXL345 device is on - typically 0 or 1
I2CAddress	The address of the ADLX345 device (default 0x53, but can be altered)

                                    {
        //this->I2CAddress = I2CAddress;
        //this->I2CBus = I2CBus;
        this->device = busDevice;
        this->accelerationX = 0;
        this->accelerationY = 0;
        this->accelerationZ = 0;
        this->pitch = 0.0f;
        this->roll = 0.0f;
        this->registers = NULL;
        this->range = ADXL345::PLUSMINUS_16_G;
        this->resolution = ADXL345::HIGH;
        this->device->writeRegister(POWER_CTL, 0x08);
        this->updateRegisters();
}

exploringBB::ADXL345::~ADXL345 ( )

virtual

{}

Member Function Documentation

void exploringBB::ADXL345::displayPitchAndRoll ( int  iterations = 600 )

virtual

Useful debug method to display the pitch and roll values in degrees on a single standard output line

Parameters

iterations

The number of 0.1s iterations to take place.

                                               {
        int count = 0;
        while(count < iterations){
              cout << "Pitch:"<< this->getPitch() << " Roll:" << this->getRoll() << "     \r"<<flush;
              usleep(100000);
              this->readSensorState();
              count++;
        }
}

virtual short exploringBB::ADXL345::getAccelerationX ( )

inlinevirtual

{ return accelerationX; }

virtual short exploringBB::ADXL345::getAccelerationY ( )

inlinevirtual

{ return accelerationY; }

virtual short exploringBB::ADXL345::getAccelerationZ ( )

inlinevirtual

{ return accelerationZ; }

virtual float exploringBB::ADXL345::getPitch ( )

inlinevirtual

{ return pitch; }

virtual ADXL345::RANGE exploringBB::ADXL345::getRange ( )

inlinevirtual

{ return this->range; }

virtual ADXL345::RESOLUTION exploringBB::ADXL345::getResolution ( )

inlinevirtual

{ return this->resolution; }

virtual float exploringBB::ADXL345::getRoll ( )

inlinevirtual

{ return roll; }

int exploringBB::ADXL345::readSensorState ( )

virtual

Read the sensor state. This method checks that the device is being correctly read by using the device ID of the ADXL345 sensor. It will read in the accelerometer registers and pass them to the combineRegisters() method to be processed.

Returns

0 if the registers are successfully read and -1 if the device ID is incorrect.

                            {
        this->registers = this->device->readRegisters(BUFFER_SIZE, 0x00);
        if(*this->registers!=0xe5){
                perror("ADXL345: Failure Condition - Sensor ID not Verified");
                return -1;
        }
        this->accelerationX = this->combineRegisters(*(registers+DATAX1), *(registers+DATAX0));
        this->accelerationY = this->combineRegisters(*(registers+DATAY1), *(registers+DATAY0));
        this->accelerationZ = this->combineRegisters(*(registers+DATAZ1), *(registers+DATAZ0));
        this->resolution = (ADXL345::RESOLUTION) (((*(registers+DATA_FORMAT))&0x08)>>3);
        this->range = (ADXL345::RANGE) ((*(registers+DATA_FORMAT))&0x03);
        this->calculatePitchAndRoll();
        return 0;
}

void exploringBB::ADXL345::setRange ( ADXL345::RANGE  range )

virtual

Set the ADXL345 gravity range according to the RANGE enumeration

Parameters

range

One of the four possible gravity ranges defined by the RANGE enumeration

                                         {
        this->range = range;
        updateRegisters();
}

void exploringBB::ADXL345::setResolution ( ADXL345::RESOLUTION  resolution )

virtual

Set the ADXL345 resolution according to the RESOLUTION enumeration

Parameters

resolution

either HIGH or NORMAL resolution. HIGH resolution is only available if the range is set to +/- 16g

                                                        {
        this->resolution = resolution;
        updateRegisters();
}

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The documentation for this class was generated from the following files:

• /home/molloyd/exploringBB/library/sensor/ADXL345.h
• /home/molloyd/exploringBB/library/sensor/ADXL345.cpp