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/**
 * @file ADXL345.cpp
 * @author Tyler Weaver
 * @author Peter Swanson
 * A personal note from me: Jesus Christ has changed my life so much it blows my mind. I say this because
 *                  today, religion is thought of as something that you do or believe and has about as
 *                  little impact on a person as their political stance. But for me, God gives me daily
 *                  strength and has filled my life with the satisfaction that I could never find in any
 *                  of the other things that I once looked for it in.
 * If your interested, heres verse that changed my life:
 *      Rom 8:1-3: "Therefore, there is now no condemnation for those who are in Christ Jesus,
 *                  because through Christ Jesus, the law of the Spirit who gives life has set
 *                  me free from the law of sin (which brings...) and death. For what the law
 *                  was powerless to do in that it was weakened by the flesh, God did by sending
 *                  His own Son in the likeness of sinful flesh to be a sin offering. And so He
 *                  condemned sin in the flesh in order that the righteous requirements of the
 *                  (God's) law might be fully met in us, who live not according to the flesh
 *                  but according to the Spirit."
 *
 *  A special thanks to Ewout van Bekkum for all his patient help in developing this library!
 *
 * @section LICENSE
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 *
 * @section DESCRIPTION
 *
 * ADXL345, triple axis, I2C interface, accelerometer.
 *
 * Datasheet:
 *
 * http://www.analog.com/static/imported-files/data_sheets/ADXL345.pdf
 */

/*
 * Includes
 */
#include "ADXL345.h"

//#include "mbed.h"

ADXL345::ADXL345(PinName sda, PinName scl) : i2c_(*(new I2C(sda, scl)))
{
    myI2c = &i2c_;
    init();
}

ADXL345::~ADXL345()
{
    delete myI2c;
}


void ADXL345::init()
{
    setDataRate(ADXL345_6HZ25); // 6.25 Hz

    setDataFormatControl(ADXL345_FULL_RES | ADXL345_2G); // full resolution, right justified, 2g range

    LocalFileSystem local("local");
    
    if(FILE *fp = fopen("/local/config.txt", "r")) { // Open "config.txt" for reading - if it doesn't exist, pass over it
        int8_t calibration_offset[3];
        DigitalOut led(LED1);
        led = 1;
        fscanf(fp, "ADXL345 x:%d,y:%d,z:%d", &calibration_offset[0], &calibration_offset[1], &calibration_offset[2]);
        fclose(fp);
        for(char axis = 0x00; axis < 0x03; axis++)
            setOffset(axis,calibration_offset[axis]);
        led = 0;
    }
}


char ADXL345::SingleByteRead(char address)
{
    char tx = address;
    char output;
    i2c_.write( ADXL345_WRITE , &tx, 1);  //tell it what you want to read
    i2c_.read( ADXL345_READ , &output, 1);    //tell it where to store the data
    return output;
}


/*
***info on the i2c_.write***
address     8-bit I2C slave address [ addr | 0 ]
data        Pointer to the byte-array data to send
length        Number of bytes to send
repeated    Repeated start, true - do not send stop at end
returns     0 on success (ack), or non-0 on failure (nack)
*/

int ADXL345::SingleByteWrite(char address, char data)
{
    int ack = 0;
    char tx[2];
    tx[0] = address;
    tx[1] = data;
    return   ack | i2c_.write( ADXL345_WRITE , tx, 2);
}


void ADXL345::multiByteRead(char address, char* output, int size)
{
    i2c_.write( ADXL345_WRITE, &address, 1);  //tell it where to read from
    i2c_.read( ADXL345_READ , output, size);      //tell it where to store the data read
}


int ADXL345::multiByteWrite(char address, char* ptr_data, int size)
{
    int ack;

    ack = i2c_.write( ADXL345_WRITE, &address, 1);  //tell it where to write to
    return ack | i2c_.write( ADXL345_READ, ptr_data, size);  //tell it what data to write
}


void ADXL345::getOutput(int16_t* readings)
{
    char buffer[6];
    multiByteRead(ADXL345_DATAX0_REG, buffer, 6);

    readings[0] = wordExtend(&buffer[0]);
    readings[1] = wordExtend(&buffer[2]);
    readings[2] = wordExtend(&buffer[4]);
}

char ADXL345::getDeviceID()
{
    return SingleByteRead(ADXL345_DEVID_REG);
}
//
int ADXL345::setPowerMode(char mode)
{
    //Get the current register contents, so we don't clobber the rate value.
    char registerContents = (mode << 4) | SingleByteRead(ADXL345_BW_RATE_REG);

    return SingleByteWrite(ADXL345_BW_RATE_REG, registerContents);
}

char ADXL345::getBwRateReg()
{
    return SingleByteRead(ADXL345_BW_RATE_REG);
}

int ADXL345::setBwRateReg(char reg)
{
    return SingleByteWrite(ADXL345_BW_RATE_REG, reg);
}

char ADXL345::getPowerControl()
{
    return SingleByteRead(ADXL345_POWER_CTL_REG);
}

int ADXL345::setPowerControl(char settings)
{
    return SingleByteWrite(ADXL345_POWER_CTL_REG, settings);

}

char ADXL345::getDataFormatControl(void)
{
    return SingleByteRead(ADXL345_DATA_FORMAT_REG);
}

int ADXL345::setDataFormatControl(char settings)
{
    return SingleByteWrite(ADXL345_DATA_FORMAT_REG, settings);
}

int ADXL345::setDataFormatControl(char settings, char mask, char *prev)
{
    char old = SingleByteRead(ADXL345_DATA_FORMAT_REG);
    if(prev)
        *prev = old;
    return SingleByteWrite(ADXL345_DATA_FORMAT_REG, (old | (settings & mask)) & (settings | ~mask));
}

int ADXL345::setDataRate(char rate)
{
    //Get the current register contents, so we don't clobber the power bit.
    char registerContents = SingleByteRead(ADXL345_BW_RATE_REG);

    registerContents &= 0x10;
    registerContents |= rate;

    return SingleByteWrite(ADXL345_BW_RATE_REG, registerContents);
}


char ADXL345::getOffset(char axis)
{
    char address = 0;

    if (axis == ADXL345_X) {
        address = ADXL345_OFSX_REG;
    } else if (axis == ADXL345_Y) {
        address = ADXL345_OFSY_REG;
    } else if (axis == ADXL345_Z) {
        address = ADXL345_OFSZ_REG;
    }

    return SingleByteRead(address);
}

int ADXL345::setOffset(char axis, char offset)
{
    char address = 0;

    if (axis == ADXL345_X) {
        address = ADXL345_OFSX_REG;
    } else if (axis == ADXL345_Y) {
        address = ADXL345_OFSY_REG;
    } else if (axis == ADXL345_Z) {
        address = ADXL345_OFSZ_REG;
    }

    return SingleByteWrite(address, offset);
}


char ADXL345::getFifoControl(void)
{
    return SingleByteRead(ADXL345_FIFO_CTL);
}

int ADXL345::setFifoControl(char settings)
{
    return SingleByteWrite(ADXL345_FIFO_STATUS, settings);
}

char ADXL345::getFifoStatus(void)
{
    return SingleByteRead(ADXL345_FIFO_STATUS);
}

char ADXL345::getTapThreshold(void)
{
    return SingleByteRead(ADXL345_THRESH_TAP_REG);
}

int ADXL345::setTapThreshold(char threshold)
{
    return SingleByteWrite(ADXL345_THRESH_TAP_REG, threshold);
}

float ADXL345::getTapDuration(void)
{
    return (float)SingleByteRead(ADXL345_DUR_REG)*625;
}

int ADXL345::setTapDuration(short int duration_us)
{
    short int tapDuration = duration_us / 625;
    char tapChar[2];
    tapChar[0] = (tapDuration & 0x00FF);
    tapChar[1] = (tapDuration >> 8) & 0x00FF;
    return multiByteWrite(ADXL345_DUR_REG, tapChar, 2);
}

float ADXL345::getTapLatency(void)
{
    return (float)SingleByteRead(ADXL345_LATENT_REG)*1.25;
}

int ADXL345::setTapLatency(short int latency_ms)
{
    latency_ms = latency_ms / 1.25;
    char latChar[2];
    latChar[0] = (latency_ms & 0x00FF);
    latChar[1] = (latency_ms << 8) & 0xFF00;
    return multiByteWrite(ADXL345_LATENT_REG, latChar, 2);
}

float ADXL345::getWindowTime(void)
{
    return (float)SingleByteRead(ADXL345_WINDOW_REG)*1.25;
}

int ADXL345::setWindowTime(short int window_ms)
{
    window_ms = window_ms / 1.25;
    char windowChar[2];
    windowChar[0] = (window_ms & 0x00FF);
    windowChar[1] = ((window_ms << 8) & 0xFF00);
    return multiByteWrite(ADXL345_WINDOW_REG, windowChar, 2);
}

char ADXL345::getActivityThreshold(void)
{
    return SingleByteRead(ADXL345_THRESH_ACT_REG);
}

int ADXL345::setActivityThreshold(char threshold)
{
    return SingleByteWrite(ADXL345_THRESH_ACT_REG, threshold);
}

char ADXL345::getInactivityThreshold(void)
{
    return SingleByteRead(ADXL345_THRESH_INACT_REG);
}

//int FUNCTION(short int * ptr_Output)
//short int FUNCTION ()

int ADXL345::setInactivityThreshold(char threshold)
{
    return SingleByteWrite(ADXL345_THRESH_INACT_REG, threshold);
}

char ADXL345::getTimeInactivity(void)
{
    return SingleByteRead(ADXL345_TIME_INACT_REG);
}

int ADXL345::setTimeInactivity(char timeInactivity)
{
    return SingleByteWrite(ADXL345_TIME_INACT_REG, timeInactivity);
}

char ADXL345::getActivityInactivityControl(void)
{
    return SingleByteRead(ADXL345_ACT_INACT_CTL_REG);
}

int ADXL345::setActivityInactivityControl(char settings)
{
    return SingleByteWrite(ADXL345_ACT_INACT_CTL_REG, settings);
}

char ADXL345::getFreefallThreshold(void)
{
    return SingleByteRead(ADXL345_THRESH_FF_REG);
}

int ADXL345::setFreefallThreshold(char threshold)
{
    return SingleByteWrite(ADXL345_THRESH_FF_REG, threshold);
}

char ADXL345::getFreefallTime(void)
{
    return SingleByteRead(ADXL345_TIME_FF_REG)*5;
}

int ADXL345::setFreefallTime(short int freefallTime_ms)
{
    freefallTime_ms = freefallTime_ms / 5;
    char fallChar[2];
    fallChar[0] = (freefallTime_ms & 0x00FF);
    fallChar[1] = (freefallTime_ms << 8) & 0xFF00;

    return multiByteWrite(ADXL345_TIME_FF_REG, fallChar, 2);
}

char ADXL345::getTapAxisControl(void)
{
    return SingleByteRead(ADXL345_TAP_AXES_REG);
}

int ADXL345::setTapAxisControl(char settings)
{
    return SingleByteWrite(ADXL345_TAP_AXES_REG, settings);
}

char ADXL345::getTapSource(void)
{
    return SingleByteRead(ADXL345_ACT_TAP_STATUS_REG);
}

char ADXL345::getInterruptEnableControl(void)
{
    return SingleByteRead(ADXL345_INT_ENABLE_REG);
}

int ADXL345::setInterruptEnableControl(char settings)
{
    return SingleByteWrite(ADXL345_INT_ENABLE_REG, settings);
}

char ADXL345::getInterruptMappingControl(void)
{
    return SingleByteRead(ADXL345_INT_MAP_REG);
}

int ADXL345::setInterruptMappingControl(char settings)
{
    return SingleByteWrite(ADXL345_INT_MAP_REG, settings);
}

char ADXL345::getInterruptSource(void)
{
    return SingleByteRead(ADXL345_INT_SOURCE_REG);
}

void ADXL345::sample100avg(float period, int16_t buffer[][3], int16_t *avg, Timer* t)
{
    double start_time;

    for(int sample = 0; sample < 100; sample++) {
        start_time = t->read();

        getOutput(buffer[sample]);

        wait(period - (start_time - t->read()));
    }

    for(int axis = 0; axis < 3; axis++) {
        double average = 0.0;
        for(int sample = 0; sample < 100; sample++)
            average += buffer[sample][axis];
        average /= 100.0;
        avg[axis] = static_cast<int16_t>(average);
    }
}

void ADXL345::calibrate(Timer* t, bool store_output, Serial *pc)
{
    int16_t data[100][3]; // {x,y,z}, data
    int16_t data_avg[3];
    int8_t calibration_offset[3];

    float period = 0.01; // period of sample rate

    // wait 11.1ms
    wait(0.0111);

    pc->puts("Reading old register states... ");
    // read current register states
    char bw_rate = getBwRateReg();
    char power_control = getPowerControl();
    char data_format = getDataFormatControl();

    pc->puts("Done!\r\nSetting new register states... ");
    // initalize command sequence
    setDataFormatControl((ADXL345_16G | ADXL345_FULL_RES));
    setBwRateReg(ADXL345_100HZ); // 100Hz data rate
    setPowerControl(0x08); // start measurement

    // wait 1.1ms
    wait(0.0111);
    pc->puts("Done!\r\nSampling... ");
    //take 100 data points and average (100Hz)
    sample100avg(period, data, data_avg, t);
    pc->puts("Done!\r\nCalculating offset values... ");
    // calculate calibration value
    calibration_offset[0] = -1 * (data_avg[0] / 4); // x
    calibration_offset[1] = -1 * (data_avg[1] / 4); // y
    calibration_offset[2] = -1 * ((data_avg[2] - 256) / 4); // z

    if(store_output) {
        pc->puts("Done!\r\nStoring output to file... ");
        LocalFileSystem local("local");
        FILE *fp = fopen("/local/OFF_CAL.csv", "w"); // write
        fprintf(fp, "ADXL345 Calibration offsets\r\nx,%d\r\ny,%d\r\nz,%d\r\n\r\n", calibration_offset[0], calibration_offset[1], calibration_offset[2]);

        fputs("Raw Data:\r\nX,Y,Z\r\n", fp);
        for(int sample = 0; sample < 100; sample++)
            fprintf(fp, "%d,%d,%d\r\n",data[sample][0],data[sample][1],data[sample][2]);
        fclose(fp);
    }
    pc->puts("Done!\r\nSetting the offset registers... ");
    // update offset registers
    for(char axis = 0x00; axis < 0x03; axis++)
        setOffset(axis,calibration_offset[axis]);
    pc->puts("Done!\r\nReturning registers to original state... ");
    // return control registers to original state
    setDataFormatControl(data_format);
    setBwRateReg(bw_rate);
    setPowerControl(power_control);
    pc->puts("Done!\r\n");
}

void ADXL345::calibrate(Timer* t, bool store_output)
{
    int16_t data[100][3]; // {x,y,z}, data
    int16_t data_avg[3];
    int8_t calibration_offset[3];

    float period = 0.01; // period of sample rate

    // wait 11.1ms
    wait(0.0111);

    // read current register states
    char bw_rate = getBwRateReg();
    char power_control = getPowerControl();
    char data_format = getDataFormatControl();

    // initalize command sequence
    setDataFormatControl((ADXL345_16G | ADXL345_FULL_RES));
    setBwRateReg(ADXL345_100HZ); // 100Hz data rate
    setPowerControl(0x08); // start measurement

    // wait 1.1ms
    wait(0.0111);
    //take 100 data points and average (100Hz)
    sample100avg(period, data, data_avg, t);
    // calculate calibration value
    calibration_offset[0] = -1 * (data_avg[0] / 4); // x
    calibration_offset[1] = -1 * (data_avg[1] / 4); // y
    calibration_offset[2] = -1 * ((data_avg[2] - 256) / 4); // z

    if(store_output) {
        LocalFileSystem local("local");
        FILE *fp = fopen("/local/OFF_CAL.csv", "w"); // write
        fprintf(fp, "ADXL345 Calibration offsets\r\nx,%d\r\ny,%d\r\nz,%d\r\n\r\n", calibration_offset[0], calibration_offset[1], calibration_offset[2]);

        fputs("Raw Data:\r\nX,Y,Z\r\n", fp);
        for(int sample = 0; sample < 100; sample++)
            fprintf(fp, "%d,%d,%d\r\n",data[sample][0],data[sample][1],data[sample][2]);
        fclose(fp);
    }
    // update offset registers
    for(char axis = 0x00; axis < 0x03; axis++)
        setOffset(axis,calibration_offset[axis]);
    // return control registers to original state
    setDataFormatControl(data_format);
    setBwRateReg(bw_rate);
    setPowerControl(power_control);
}