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/**************************************************************************
* *
* ADXL345 Driver for Arduino *
* *
***************************************************************************
* *
* This program is free software; you can redistribute it and/or modify *
* it under the terms of the GNU License. *
* This program is distributed in the hope that it will be useful, *
* but WITHOUT ANY WARRANTY; without even the implied warranty of *
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the *
* GNU License V2 for more details. *
* *
***************************************************************************/
#include "WProgram.h"
#include "ADXL345.h"
#include <Wire.h>
#define TO_READ (6) // num of bytes we are going to read each time (two bytes for each axis)
ADXL345::ADXL345() {
status = ADXL345_OK;
error_code = ADXL345_NO_ERROR;
gains[0] = 0.00376390;
gains[1] = 0.00376009;
gains[2] = 0.00349265;
}
void ADXL345::init(int address) {
_dev_address = address;
powerOn();
}
void ADXL345::powerOn() {
//Turning on the ADXL345
//writeTo(ADXL345_POWER_CTL, 0);
//writeTo(ADXL345_POWER_CTL, 16);
writeTo(ADXL345_POWER_CTL, 8);
}
// Reads the acceleration into an array of three places
void ADXL345::readAccel(int *xyz){
readAccel(xyz, xyz + 1, xyz + 2);
}
// Reads the acceleration into three variable x, y and z
void ADXL345::readAccel(int *x, int *y, int *z) {
readFrom(ADXL345_DATAX0, 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
*x = (((int)_buff[1]) << 8) | _buff[0];
*y = (((int)_buff[3]) << 8) | _buff[2];
*z = (((int)_buff[5]) << 8) | _buff[4];
}
void ADXL345::get_Gxyz(float *xyz){
int i;
int xyz_int[3];
readAccel(xyz_int);
for(i=0; i<3; i++){
xyz[i] = xyz_int[i] * gains[i];
}
}
// Writes val to address register on device
void ADXL345::writeTo(byte address, byte val) {
Wire.beginTransmission(_dev_address); // start transmission to device
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 device in to _buff array
void ADXL345::readFrom(byte address, int num, byte _buff[]) {
Wire.beginTransmission(_dev_address); // start transmission to device
Wire.send(address); // sends address to read from
Wire.endTransmission(); // end transmission
Wire.beginTransmission(_dev_address); // start transmission to device
Wire.requestFrom(_dev_address, num); // request 6 bytes from device
int i = 0;
while(Wire.available()) // device may send less than requested (abnormal)
{
_buff[i] = Wire.receive(); // receive a byte
i++;
}
if(i != num){
status = ADXL345_ERROR;
error_code = ADXL345_READ_ERROR;
}
Wire.endTransmission(); // end transmission
}
// Gets the range setting and return it into rangeSetting
// it can be 2, 4, 8 or 16
void ADXL345::getRangeSetting(byte* rangeSetting) {
byte _b;
readFrom(ADXL345_DATA_FORMAT, 1, &_b);
*rangeSetting = _b & B00000011;
}
// Sets the range setting, possible values are: 2, 4, 8, 16
void ADXL345::setRangeSetting(int val) {
byte _s;
byte _b;
switch (val) {
case 2:
_s = B00000000;
break;
case 4:
_s = B00000001;
break;
case 8:
_s = B00000010;
break;
case 16:
_s = B00000011;
break;
default:
_s = B00000000;
}
readFrom(ADXL345_DATA_FORMAT, 1, &_b);
_s |= (_b & B11101100);
writeTo(ADXL345_DATA_FORMAT, _s);
}
// gets the state of the SELF_TEST bit
bool ADXL345::getSelfTestBit() {
return getRegisterBit(ADXL345_DATA_FORMAT, 7);
}
// Sets the SELF-TEST bit
// if set to 1 it applies a self-test force to the sensor causing a shift in the output data
// if set to 0 it disables the self-test force
void ADXL345::setSelfTestBit(bool selfTestBit) {
setRegisterBit(ADXL345_DATA_FORMAT, 7, selfTestBit);
}
// Gets the state of the SPI bit
bool ADXL345::getSpiBit() {
return getRegisterBit(ADXL345_DATA_FORMAT, 6);
}
// Sets the SPI bit
// if set to 1 it sets the device to 3-wire mode
// if set to 0 it sets the device to 4-wire SPI mode
void ADXL345::setSpiBit(bool spiBit) {
setRegisterBit(ADXL345_DATA_FORMAT, 6, spiBit);
}
// Gets the state of the INT_INVERT bit
bool ADXL345::getInterruptLevelBit() {
return getRegisterBit(ADXL345_DATA_FORMAT, 5);
}
// Sets the INT_INVERT bit
// if set to 0 sets the interrupts to active high
// if set to 1 sets the interrupts to active low
void ADXL345::setInterruptLevelBit(bool interruptLevelBit) {
setRegisterBit(ADXL345_DATA_FORMAT, 5, interruptLevelBit);
}
// Gets the state of the FULL_RES bit
bool ADXL345::getFullResBit() {
return getRegisterBit(ADXL345_DATA_FORMAT, 3);
}
// Sets the FULL_RES bit
// if set to 1, the device is in full resolution mode, where the output resolution increases with the
// g range set by the range bits to maintain a 4mg/LSB scal factor
// if set to 0, the device is in 10-bit mode, and the range buts determine the maximum g range
// and scale factor
void ADXL345::setFullResBit(bool fullResBit) {
setRegisterBit(ADXL345_DATA_FORMAT, 3, fullResBit);
}
// Gets the state of the justify bit
bool ADXL345::getJustifyBit() {
return getRegisterBit(ADXL345_DATA_FORMAT, 2);
}
// Sets the JUSTIFY bit
// if sets to 1 selects the left justified mode
// if sets to 0 selects right justified mode with sign extension
void ADXL345::setJustifyBit(bool justifyBit) {
setRegisterBit(ADXL345_DATA_FORMAT, 2, justifyBit);
}
// Sets the THRESH_TAP byte value
// it should be between 0 and 255
// the scale factor is 62.5 mg/LSB
// A value of 0 may result in undesirable behavior
void ADXL345::setTapThreshold(int tapThreshold) {
tapThreshold = min(max(tapThreshold,0),255);
byte _b = byte (tapThreshold);
writeTo(ADXL345_THRESH_TAP, _b);
}
// Gets the THRESH_TAP byte value
// return value is comprised between 0 and 255
// the scale factor is 62.5 mg/LSB
int ADXL345::getTapThreshold() {
byte _b;
readFrom(ADXL345_THRESH_TAP, 1, &_b);
return int (_b);
}
// set/get the gain for each axis in Gs / count
void ADXL345::setAxisGains(float *_gains){
int i;
for(i = 0; i < 3; i++){
gains[i] = _gains[i];
}
}
void ADXL345::getAxisGains(float *_gains){
int i;
for(i = 0; i < 3; i++){
_gains[i] = gains[i];
}
}
// Sets the OFSX, OFSY and OFSZ bytes
// OFSX, OFSY and OFSZ are user offset adjustments in twos complement format with
// a scale factor of 15,6mg/LSB
// OFSX, OFSY and OFSZ should be comprised between
void ADXL345::setAxisOffset(int x, int y, int z) {
writeTo(ADXL345_OFSX, byte (x));
writeTo(ADXL345_OFSY, byte (y));
writeTo(ADXL345_OFSZ, byte (z));
}
// Gets the OFSX, OFSY and OFSZ bytes
void ADXL345::getAxisOffset(int* x, int* y, int*z) {
byte _b;
readFrom(ADXL345_OFSX, 1, &_b);
*x = int (_b);
readFrom(ADXL345_OFSY, 1, &_b);
*y = int (_b);
readFrom(ADXL345_OFSZ, 1, &_b);
*z = int (_b);
}
// Sets the DUR byte
// The DUR byte contains an unsigned time value representing the maximum time
// that an event must be above THRESH_TAP threshold to qualify as a tap event
// The scale factor is 625µs/LSB
// A value of 0 disables the tap/float tap funcitons. Max value is 255.
void ADXL345::setTapDuration(int tapDuration) {
tapDuration = min(max(tapDuration,0),255);
byte _b = byte (tapDuration);
writeTo(ADXL345_DUR, _b);
}
// Gets the DUR byte
int ADXL345::getTapDuration() {
byte _b;
readFrom(ADXL345_DUR, 1, &_b);
return int (_b);
}
// Sets the latency (latent register) which contains an unsigned time value
// representing the wait time from the detection of a tap event to the start
// of the time window, during which a possible second tap can be detected.
// The scale factor is 1.25ms/LSB. A value of 0 disables the float tap function.
// It accepts a maximum value of 255.
void ADXL345::setDoubleTapLatency(int floatTapLatency) {
byte _b = byte (floatTapLatency);
writeTo(ADXL345_LATENT, _b);
}
// Gets the Latent value
int ADXL345::getDoubleTapLatency() {
byte _b;
readFrom(ADXL345_LATENT, 1, &_b);
return int (_b);
}
// Sets the Window register, which contains an unsigned time value representing
// the amount of time after the expiration of the latency time (Latent register)
// during which a second valud tap can begin. The scale factor is 1.25ms/LSB. A
// value of 0 disables the float tap function. The maximum value is 255.
void ADXL345::setDoubleTapWindow(int floatTapWindow) {
floatTapWindow = min(max(floatTapWindow,0),255);
byte _b = byte (floatTapWindow);
writeTo(ADXL345_WINDOW, _b);
}
// Gets the Window register
int ADXL345::getDoubleTapWindow() {
byte _b;
readFrom(ADXL345_WINDOW, 1, &_b);
return int (_b);
}
// Sets the THRESH_ACT byte which holds the threshold value for detecting activity.
// The data format is unsigned, so the magnitude of the activity event is compared
// with the value is compared with the value in the THRESH_ACT register. The scale
// factor is 62.5mg/LSB. A value of 0 may result in undesirable behavior if the
// activity interrupt is enabled. The maximum value is 255.
void ADXL345::setActivityThreshold(int activityThreshold) {
activityThreshold = min(max(activityThreshold,0),255);
byte _b = byte (activityThreshold);
writeTo(ADXL345_THRESH_ACT, _b);
}
// Gets the THRESH_ACT byte
int ADXL345::getActivityThreshold() {
byte _b;
readFrom(ADXL345_THRESH_ACT, 1, &_b);
return int (_b);
}
// Sets the THRESH_INACT byte which holds the threshold value for detecting inactivity.
// The data format is unsigned, so the magnitude of the inactivity event is compared
// with the value is compared with the value in the THRESH_INACT register. The scale
// factor is 62.5mg/LSB. A value of 0 may result in undesirable behavior if the
// inactivity interrupt is enabled. The maximum value is 255.
void ADXL345::setInactivityThreshold(int inactivityThreshold) {
inactivityThreshold = min(max(inactivityThreshold,0),255);
byte _b = byte (inactivityThreshold);
writeTo(ADXL345_THRESH_INACT, _b);
}
// Gets the THRESH_INACT byte
int ADXL345::getInactivityThreshold() {
byte _b;
readFrom(ADXL345_THRESH_INACT, 1, &_b);
return int (_b);
}
// Sets the TIME_INACT register, which contains an unsigned time value representing the
// amount of time that acceleration must be less thant the value in the THRESH_INACT
// register for inactivity to be declared. The scale factor is 1sec/LSB. The value must
// be between 0 and 255.
void ADXL345::setTimeInactivity(int timeInactivity) {
timeInactivity = min(max(timeInactivity,0),255);
byte _b = byte (timeInactivity);
writeTo(ADXL345_TIME_INACT, _b);
}
// Gets the TIME_INACT register
int ADXL345::getTimeInactivity() {
byte _b;
readFrom(ADXL345_TIME_INACT, 1, &_b);
return int (_b);
}
// Sets the THRESH_FF register which holds the threshold value, in an unsigned format, for
// free-fall detection. The root-sum-square (RSS) value of all axes is calculated and
// compared whith the value in THRESH_FF to determine if a free-fall event occured. The
// scale factor is 62.5mg/LSB. A value of 0 may result in undesirable behavior if the free-fall
// interrupt is enabled. The maximum value is 255.
void ADXL345::setFreeFallThreshold(int freeFallThreshold) {
freeFallThreshold = min(max(freeFallThreshold,0),255);
byte _b = byte (freeFallThreshold);
writeTo(ADXL345_THRESH_FF, _b);
}
// Gets the THRESH_FF register.
int ADXL345::getFreeFallThreshold() {
byte _b;
readFrom(ADXL345_THRESH_FF, 1, &_b);
return int (_b);
}
// Sets the TIME_FF register, which holds an unsigned time value representing the minimum
// time that the RSS value of all axes must be less than THRESH_FF to generate a free-fall
// interrupt. The scale factor is 5ms/LSB. A value of 0 may result in undesirable behavior if
// the free-fall interrupt is enabled. The maximum value is 255.
void ADXL345::setFreeFallDuration(int freeFallDuration) {
freeFallDuration = min(max(freeFallDuration,0),255);
byte _b = byte (freeFallDuration);
writeTo(ADXL345_TIME_FF, _b);
}
// Gets the TIME_FF register.
int ADXL345::getFreeFallDuration() {
byte _b;
readFrom(ADXL345_TIME_FF, 1, &_b);
return int (_b);
}
bool ADXL345::isActivityXEnabled() {
return getRegisterBit(ADXL345_ACT_INACT_CTL, 6);
}
bool ADXL345::isActivityYEnabled() {
return getRegisterBit(ADXL345_ACT_INACT_CTL, 5);
}
bool ADXL345::isActivityZEnabled() {
return getRegisterBit(ADXL345_ACT_INACT_CTL, 4);
}
bool ADXL345::isInactivityXEnabled() {
return getRegisterBit(ADXL345_ACT_INACT_CTL, 2);
}
bool ADXL345::isInactivityYEnabled() {
return getRegisterBit(ADXL345_ACT_INACT_CTL, 1);
}
bool ADXL345::isInactivityZEnabled() {
return getRegisterBit(ADXL345_ACT_INACT_CTL, 0);
}
void ADXL345::setActivityX(bool state) {
setRegisterBit(ADXL345_ACT_INACT_CTL, 6, state);
}
void ADXL345::setActivityY(bool state) {
setRegisterBit(ADXL345_ACT_INACT_CTL, 5, state);
}
void ADXL345::setActivityZ(bool state) {
setRegisterBit(ADXL345_ACT_INACT_CTL, 4, state);
}
void ADXL345::setInactivityX(bool state) {
setRegisterBit(ADXL345_ACT_INACT_CTL, 2, state);
}
void ADXL345::setInactivityY(bool state) {
setRegisterBit(ADXL345_ACT_INACT_CTL, 1, state);
}
void ADXL345::setInactivityZ(bool state) {
setRegisterBit(ADXL345_ACT_INACT_CTL, 0, state);
}
bool ADXL345::isActivityAc() {
return getRegisterBit(ADXL345_ACT_INACT_CTL, 7);
}
bool ADXL345::isInactivityAc(){
return getRegisterBit(ADXL345_ACT_INACT_CTL, 3);
}
void ADXL345::setActivityAc(bool state) {
setRegisterBit(ADXL345_ACT_INACT_CTL, 7, state);
}
void ADXL345::setInactivityAc(bool state) {
setRegisterBit(ADXL345_ACT_INACT_CTL, 3, state);
}
bool ADXL345::getSuppressBit(){
return getRegisterBit(ADXL345_TAP_AXES, 3);
}
void ADXL345::setSuppressBit(bool state) {
setRegisterBit(ADXL345_TAP_AXES, 3, state);
}
bool ADXL345::isTapDetectionOnX(){
return getRegisterBit(ADXL345_TAP_AXES, 2);
}
void ADXL345::setTapDetectionOnX(bool state) {
setRegisterBit(ADXL345_TAP_AXES, 2, state);
}
bool ADXL345::isTapDetectionOnY(){
return getRegisterBit(ADXL345_TAP_AXES, 1);
}
void ADXL345::setTapDetectionOnY(bool state) {
setRegisterBit(ADXL345_TAP_AXES, 1, state);
}
bool ADXL345::isTapDetectionOnZ(){
return getRegisterBit(ADXL345_TAP_AXES, 0);
}
void ADXL345::setTapDetectionOnZ(bool state) {
setRegisterBit(ADXL345_TAP_AXES, 0, state);
}
bool ADXL345::isActivitySourceOnX(){
return getRegisterBit(ADXL345_ACT_TAP_STATUS, 6);
}
bool ADXL345::isActivitySourceOnY(){
return getRegisterBit(ADXL345_ACT_TAP_STATUS, 5);
}
bool ADXL345::isActivitySourceOnZ(){
return getRegisterBit(ADXL345_ACT_TAP_STATUS, 4);
}
bool ADXL345::isTapSourceOnX(){
return getRegisterBit(ADXL345_ACT_TAP_STATUS, 2);
}
bool ADXL345::isTapSourceOnY(){
return getRegisterBit(ADXL345_ACT_TAP_STATUS, 1);
}
bool ADXL345::isTapSourceOnZ(){
return getRegisterBit(ADXL345_ACT_TAP_STATUS, 0);
}
bool ADXL345::isAsleep(){
return getRegisterBit(ADXL345_ACT_TAP_STATUS, 3);
}
bool ADXL345::isLowPower(){
return getRegisterBit(ADXL345_BW_RATE, 4);
}
void ADXL345::setLowPower(bool state) {
setRegisterBit(ADXL345_BW_RATE, 4, state);
}
float ADXL345::getRate(){
byte _b;
readFrom(ADXL345_BW_RATE, 1, &_b);
_b &= B00001111;
return (pow(2,((int) _b)-6)) * 6.25;
}
void ADXL345::setRate(float rate){
byte _b,_s;
int v = (int) (rate / 6.25);
int r = 0;
while (v >>= 1)
{
r++;
}
if (r <= 9) {
readFrom(ADXL345_BW_RATE, 1, &_b);
_s = (byte) (r + 6) | (_b & B11110000);
writeTo(ADXL345_BW_RATE, _s);
}
}
void ADXL345::set_bw(byte bw_code){
if((bw_code < ADXL345_BW_3) || (bw_code > ADXL345_BW_1600)){
status = false;
error_code = ADXL345_BAD_ARG;
}
else{
writeTo(ADXL345_BW_RATE, bw_code);
}
}
byte ADXL345::get_bw_code(){
byte bw_code;
readFrom(ADXL345_BW_RATE, 1, &bw_code);
return bw_code;
}
byte ADXL345::getInterruptSource() {
byte _b;
readFrom(ADXL345_INT_SOURCE, 1, &_b);
return _b;
}
bool ADXL345::getInterruptSource(byte interruptBit) {
return getRegisterBit(ADXL345_INT_SOURCE,interruptBit);
}
bool ADXL345::getInterruptMapping(byte interruptBit) {
return getRegisterBit(ADXL345_INT_MAP,interruptBit);
}
// Set the mapping of an interrupt to pin1 or pin2
// eg: setInterruptMapping(ADXL345_INT_DOUBLE_TAP_BIT,ADXL345_INT2_PIN);
void ADXL345::setInterruptMapping(byte interruptBit, bool interruptPin) {
setRegisterBit(ADXL345_INT_MAP, interruptBit, interruptPin);
}
bool ADXL345::isInterruptEnabled(byte interruptBit) {
return getRegisterBit(ADXL345_INT_ENABLE,interruptBit);
}
void ADXL345::setInterrupt(byte interruptBit, bool state) {
setRegisterBit(ADXL345_INT_ENABLE, interruptBit, state);
}
void ADXL345::setRegisterBit(byte regAdress, int bitPos, bool state) {
byte _b;
readFrom(regAdress, 1, &_b);
if (state) {
_b |= (1 << bitPos); // forces nth bit of _b to be 1. all other bits left alone.
}
else {
_b &= ~(1 << bitPos); // forces nth bit of _b to be 0. all other bits left alone.
}
writeTo(regAdress, _b);
}
bool ADXL345::getRegisterBit(byte regAdress, int bitPos) {
byte _b;
readFrom(regAdress, 1, &_b);
return ((_b >> bitPos) & 1);
}
// print all register value to the serial ouptut, which requires it to be setup
// this can be used to manually to check the current configuration of the device
void ADXL345::printAllRegister() {
byte _b;
Serial.print("0x00: ");
readFrom(0x00, 1, &_b);
print_byte(_b);
Serial.println("");
int i;
for (i=29;i<=57;i++){
Serial.print("0x");
Serial.print(i, HEX);
Serial.print(": ");
readFrom(i, 1, &_b);
print_byte(_b);
Serial.println("");
}
}
void print_byte(byte val){
int i;
Serial.print("B");
for(i=7; i>=0; i--){
Serial.print(val >> i & 1, BIN);
}
}