File content as of revision 0:15e41c824e3b:

#include "angle.h"
#include "mbed.h"
ANGLE::ANGLE(PinName sda, PinName scl) : i2c_(sda, scl) {
    Rate=0.00390635;sampleTime=0.001;sampleNum=500;

    kalma[0].setAngle(0);
    kalma[1].setAngle(0);
    kalma[2].setAngle(0);
    //400kHz, allowing us to use the fastest data rates.
    i2c_.frequency(400000);
    // initialize the BW data rate
    char tx[2];
    tx[0] = ADXL345_BW_RATE_REG;
    tx[1] = ADXL345_200HZ; //value greater than or equal to 0x0A is written into the rate bits (Bit D3 through Bit D0) in the BW_RATE register 
    i2c_.write( acc_i2c_write , tx, 2);  
    
    //Data format (for +-16g) - This is done by setting Bit D3 of the DATA_FORMAT register (Address 0x31) and writing a value of 0x03 to the range bits (Bit D1 and Bit D0) of the DATA_FORMAT register (Address 0x31).
    
    char rx[2];
    rx[0] = ADXL345_DATA_FORMAT_REG;
    rx[1] = 0x0B; 
     // full res and +_16g
    i2c_.write( acc_i2c_write , rx, 2); 
    
    // Set Offset  - programmed into the OFSX, OFSY, and OFXZ registers, respectively, as 0xFD, 0x03 and 0xFE.
    char x[2];
    x[0] = ADXL345_OFSX_REG ;
    x[1] = 253; 
    i2c_.write( acc_i2c_write , x, 2);
    char y[2];
    y[0] = ADXL345_OFSY_REG ;
    y[1] = 5; 
    i2c_.write( acc_i2c_write, y, 2);
    char z[2];
    z[0] = ADXL345_OFSZ_REG ;
    z[1] = 0xFE; 
    i2c_.write( acc_i2c_write , z, 2);
     char reg_v;
    sampleTime=0.001;
    sampleNum=500;
    angle[0]=angle[1]=angle[2]=0;
    prev_rate[0]=prev_rate[1]=prev_rate[2]=0;
    
    // 0x0F = 0b00001111
    // Normal power mode, all axes enabled
    reg_v = 0;
    reg_v |= 0x0F;
    write_reg(GYR_ADDRESS,L3GD20_CTRL_REG1,reg_v);
    set_offset();
    set_noise();
    
    offset_angle[0]=0;
    offset_angle[1]=0;
    offset_angle[2]=0;
    ADXL_setup();
    set_angleoffset();
    }
void ANGLE::ADXL_setup(){
      z_offset=2;x_offset=0;y_offset=0;
      char buffer[6];    

          for(int i=0;i<sampleNum;i++)
  {
        data_multi_get(ADXL345_DATAX0_REG, buffer, 6);
        int Xacc = (int)buffer[1] << 8 | (int)buffer[0];
        int Yacc = (int)buffer[3] << 8 | (int)buffer[2];
        int Zacc = (int)buffer[5] << 8 | (int)buffer[4]-255;
    if((int)Xacc-x_offset>xnoise)
      xnoise=(int)Xacc-x_offset;
    else if((int)Xacc-x_offset<-xnoise)
      xnoise=-(int)Xacc-x_offset;

    if((int)Yacc-y_offset>ynoise)
      ynoise=(int)Yacc-y_offset;
    else if((int)Yacc-y_offset<-ynoise)
      ynoise=-(int)Yacc-y_offset; 

    if((int)Zacc-z_offset>znoise)
      znoise=(int)Zacc-z_offset;
    else if((int)Zacc-z_offset<-znoise)
      znoise=-(int)Zacc-z_offset; 
  }
        
      
}
void ANGLE::ADXL_setnum(int Num,float time,double rate){
        sampleNum=Num;sampleTime=time;Rate=rate;
}
char ANGLE::data_single_get(char reg){   
   char tx = reg;
   char output; 
    i2c_.write( acc_i2c_write , &tx, 1);  //tell it what you want to read
    i2c_.read( acc_i2c_read , &output, 1);    //tell it where to store the data
    return output;
}
int ANGLE::data_single_put(char reg, char data){ 
   int ack = 0;
   char tx[2];
   tx[0] = reg;
   tx[1] = data;
   return   ack | i2c_.write( acc_i2c_write , tx, 2);   
}



void ANGLE::data_multi_get(char reg, char* data, int size) {
    i2c_.write( acc_i2c_write, &reg, 1);  //tell it where to read from
    i2c_.read( acc_i2c_read , data, size);      //tell it where to store the data read
}


int ANGLE::data_multi_put(char reg, char* data, int size) {
        int ack;
   
               ack = i2c_.write( acc_i2c_write, &reg, 1);  //tell it where to write to
        return ack | i2c_.write( acc_i2c_read, data, size);  //tell it what data to write                                   
}
void ANGLE::getangle_acc(double* DATA_ANGLE){
    char buffer[6];
    short data[3];    
    //data_multi_get(ADXL345_DATAX0_REG, buffer, 6);
    getaxis_acc(data);
      // calculate the absolute of the magnetic field vector                                    // 8-Bit pieces of axis data
      // read axis registers using I2C
    
    /*data[0] = (short) (buffer[1] << 8 | buffer[0]);//-x_offset;     // join 8-Bit pieces to 16-bit short integers
    data[1] = (short) (buffer[3] << 8 | buffer[2]);//-y_offset;
    data[2] = (short) (buffer[5] << 8 | buffer[4]);//-z_offset;*/
    float R = sqrt(pow((float)data[0],2) + pow((float)data[1],2) + pow((float)data[2],2));
    DATA_ANGLE[1] =   -((180 / 3.1415) * acos((float)data[1] / R)-90);                                    // roll - angle of magnetic field vector in x direction
    DATA_ANGLE[0] =   (180 / 3.1415) * acos((float)data[0] / R)-90;                                    // pitch - angle of magnetic field vector in y direction
    DATA_ANGLE[2] =   (180 / 3.1415) * acos((float)data[2] / R); //*/
    DATA_ANGLE[0] = atan2(data[0],sqrt(pow((float)data[1],2)+pow((float)data[2],2)))*180/3.1415;
    DATA_ANGLE[1] = atan2(data[1],sqrt(pow((float)data[0],2)+pow((float)data[2],2)))*180/3.1415;
    DATA_ANGLE[2] = atan2(sqrt(pow((float)data[1],2)+pow((float)data[2],2)),data[2])*180/3.1415;
   /*DATA_ANGLE[0]=atan2((double)data[0],(double)data[2])* (180 / 3.1415);
    DATA_ANGLE[1]=atan2((double)data[1],(double)data[2])* (180 / 3.1415);
   /* if(data[0]>255)
      DATA_ANGLE[0]=-90;
    else if(data[0]<-263)
      DATA_ANGLE[0]=90;
    if(data[1]>260)
      DATA_ANGLE[1]=90;
    else if(data[1]<-246)
      DATA_ANGLE[1]=-90;
    /*if(DATA[1]>250)
      DATA_ANGLE[1]=90;
    else if(DATA[1]<-260)
      DATA_ANGLE[1]=-90;
    if(DATA[0]>250)
      DATA_ANGLE[0]=90;
    else if(DATA[0]<-260)
      DATA_ANGLE[0]=-90;*/
      }
void ANGLE::getaxis_acc(short* DATA_ACC){
    char buffer[6];
    data_multi_get(ADXL345_DATAX0_REG, buffer, 6);
    
    DATA_ACC[0] = ((short)buffer[1] << 8 | (short)buffer[0]);//+0.1*tempDATA_ACC[0];//-x_offset;
    DATA_ACC[1] = ((short)buffer[3] << 8 | (short)buffer[2]);//+0.1*tempDATA_ACC[1];//-y_offset;
    DATA_ACC[2] = ((short)buffer[5] << 8 | (short)buffer[4]);//+0.1*tempDATA_ACC[2];//-z_offset;
    DATA_ACC[0] = (short)(DATA_ACC[0]*0.9+tempDATA_ACC[0]*0.1);
    DATA_ACC[1] = (short)(DATA_ACC[1]*0.9+tempDATA_ACC[0]*0.1);
    DATA_ACC[2] = (short)(DATA_ACC[2]*0.9+tempDATA_ACC[0]*0.1);
    tempDATA_ACC[0]=DATA_ACC[0];
    tempDATA_ACC[1]=DATA_ACC[1];
    tempDATA_ACC[2]=DATA_ACC[2];//*/
}
void ANGLE::get_rate(short* RATE)
{
    short axis[3];
    short offset_t[3]={-1,+1,0};
    read(axis);
    for(int i=0; i<3; i++){
        RATE[i]=(short)(axis[i])*0.01-offset_t[i];
        //RATE[i]=(floor(RATE[i]));
        }
}
void ANGLE::get_angle(double *x,double *y,double *z)
{
    *x=(floor(angle[0]*100.0)/100.0);
    *y=(floor(angle[1]*100.0)/100.0);
    *z=(floor(angle[2]*100.0)/100.0);
}
void ANGLE::get_angle_rate(double *x,double *y,double *z)
{
    
    *x=t[0];
    *y=t[1];
    *z=t[2];
}

void ANGLE::get_Synthesis_angle(double* X,double* Y)
{
        *X=Synthesis_angle[0];
        *Y=Synthesis_angle[1];
}
void ANGLE::get_Comp_angle(double* X,double* Y)
{
        *X=comp_angle[0];
        *Y=comp_angle[1];
}
void ANGLE::get_Kalman_angle(double* X,double* Y)
{
        *X=kalman_angle[0];
        *Y=kalman_angle[1];
}
void ANGLE::set_angle(double ANG_x,double ANG_y,double ANG_z)
{
    Synthesis_angle[0]=angle[0]=ANG_x;
    Synthesis_angle[1]=angle[1]=ANG_y;
    angle[2]=ANG_z;
}
void ANGLE::set_angle()
{
    get_rate(rate);
    double g[3], d[3];
    get_angle(g,g+1,g+2);
    getangle_acc(d);
    double S[3];
    for(int i=0; i<3; i++) {
        //rate[i]=rate[i]*0.00875;
        
        S[i]  =((double)(rate[i]+prev_rate[i])*sampleTime/2);
        // S[i]=(floor(S[i]*100.0)/100.0);//-offset_angle[i];
        //angle[i]+=(floor(t[i]*100.0)/100.0);//-offset_angle[i];
        angle[i]+=(double)S[i];
        Synthesis_angle[i]+=(double)S[i];
        Synthesis_angle[i]=0.99*(double)(Synthesis_angle[i]+(double)rate[i]/1020.5)+0.01*d[i];
        kalman_angle[i]=kalma[i].getAngle((double)d[i], (double)rate[i], (double)sampleTime*1000);
        comp_angle[i]=kalman_angle[i]*0.01+Synthesis_angle[i]*0.01+comp_angle[i]*0.98;
        prev_rate[i]=rate[i];
    }
}
void ANGLE::set_angleoffset()
{
     double axis[3],offseta[3];
     offseta[0]=offseta[1]=offseta[2]=0;
    offset_angle[0]=0;
    offset_angle[1]=0;
    offset_angle[2]=0;
    for(int i=0; i<sampleNum; i++) {
        set_angle();
        get_angle_rate(axis,axis+1,axis+2);
        offseta[0]+=axis[0];
        offseta[1]+=axis[1];
        offseta[2]+=axis[2];
    }
    offset_angle[0]=offseta[0]/sampleNum;
    offset_angle[1]=offseta[1]/sampleNum;
    offset_angle[2]=offseta[2]/sampleNum;
    offset_angle[0]=(floor(offset_angle[0]*100.0)/100.0);
    offset_angle[1]=(floor(offset_angle[1]*100.0)/100.0);
    offset_angle[2]=(floor(offset_angle[2]*100.0)/100.0);
    angle[0]=0;
    angle[1]=0;
    angle[2]=0;
}
void ANGLE::set_noise()
{
    short gyal[3];
    noise[0]=noise[1]=noise[2]=0;

    for(int i=0; i<sampleNum; i++) {

        for(int t=0; t<3; t++) {
            read(gyal);
            if((int)gyal[t]>noise[t])
                noise[t]=(int)gyal[t];
            else if((int)gyal[t]<-noise[t])
                noise[t]=-(int)gyal[t];
        }
    }
    noise[0]*=sampleTime;
    noise[1]*=sampleTime;
    noise[2]*=sampleTime;
}
void ANGLE::set_offset()
{
    short axis[3],offseta[3];
    offseta[0]=0;
    offseta[1]=0;
    offseta[2]=0;
    for(int i=0; i<sampleNum; i++) {
        read(axis);
        offseta[0]+=axis[0];
        offseta[1]+=axis[1];
        offseta[2]+=axis[2];
    }
    offset[0]=offseta[0]/sampleNum;
    offset[1]=offseta[1]/sampleNum;
    offset[2]=offseta[2]/sampleNum;
}
bool ANGLE::read(short *axis)
{
    char gyr[6];

    if (recv(GYR_ADDRESS, L3GD20_OUT_X_L, gyr, 6)) {
        //scale is 8.75 mdps/digit
        axis[0] =  (short(gyr[1] << 8 | gyr[0]))-offset[0];
        axis[1] =  (short(gyr[3] << 8 | gyr[2]))-offset[1];
        axis[2] =  (short(gyr[5] << 8 | gyr[4]))-offset[2];


        return true;
    }

    return false;
}
bool ANGLE::read(float *gx, float *gy, float *gz)
{
    char gyr[6];

    if (recv(GYR_ADDRESS, L3GD20_OUT_X_L, gyr, 6)) {
        //scale is 8.75 mdps/digit
        *gx =  float(short(gyr[1] << 8 | gyr[0])-offset[0])*0.00875*sampleTime;
        *gy =  float(short(gyr[3] << 8 | gyr[2])-offset[1])*0.00875*sampleTime;
        *gz =  float(short(gyr[5] << 8 | gyr[4])-offset[2])*0.00875*sampleTime;


        return true;
    }

    return false;
}




bool ANGLE::write_reg(int addr_i2c,int addr_reg, char v)
{
    char data[2] = {addr_reg, v};
    return ANGLE::i2c_.write(addr_i2c, data, 2) == 0;
}

bool ANGLE::read_reg(int addr_i2c,int addr_reg, char *v)
{
    char data = addr_reg;
    bool result = false;

    __disable_irq();
    if ((i2c_.write(addr_i2c, &data, 1) == 0) && (i2c_.read(addr_i2c, &data, 1) == 0)) {
        *v = data;
        result = true;
    }
    __enable_irq();
    return result;
}


bool ANGLE::recv(char sad, char sub, char *buf, int length)
{
    if (length > 1) sub |= 0x80;

    return i2c_.write(sad, &sub, 1, true) == 0 && i2c_.read(sad, buf, length) == 0;
}
int ANGLE::setPowerMode(char mode) { 

    //Get the current register contents, so we don't clobber the rate value.
    char registerContents = (mode << 4) | data_single_get(ADXL345_BW_RATE_REG);

   return data_single_put(ADXL345_BW_RATE_REG, registerContents);

}
int ANGLE::setDataRate(char rate) {

    //Get the current register contents, so we don't clobber the power bit.
    char registerContents = data_single_get(ADXL345_BW_RATE_REG);

    registerContents &= 0x10;
    registerContents |= rate;

    return data_single_put(ADXL345_BW_RATE_REG, registerContents);

}
char ANGLE::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 data_single_get(address);
}

int ANGLE::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 data_single_put(address, offset);

}
int ANGLE::setTapDuration(short int duration_us) {

    short int tapDuration = duration_us / 625;
    char tapChar[2];
     tapChar[0] = (tapDuration & 0x00FF);
     tapChar[1] = (tapDuration >> 8) & 0x00FF;
    return data_multi_put(ADXL345_DUR_REG, tapChar, 2);

}
int ANGLE::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 data_multi_put(ADXL345_LATENT_REG, latChar, 2);

}
int ANGLE::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 data_multi_put(ADXL345_WINDOW_REG, windowChar, 2);

}
int ANGLE::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 data_multi_put(ADXL345_TIME_FF_REG, fallChar, 2);

}
ANGLE::kalman::kalman(void){
    P[0][0]     = 0;
    P[0][1]     = 0;
    P[1][0]     = 0;
    P[1][1]     = 0;
    
    angle       = 0;
    bias        = 0;
    
    Q_angle     = 0.001;
    Q_gyroBias  = 0.003;
    R_angle     = 0.03;     
}

double ANGLE::kalman::getAngle(double newAngle, double newRate, double dt){
    //predict the angle according to the gyroscope
    rate         = newRate - bias;
    angle        = dt * rate;
    //update the error covariance
    P[0][0]     += dt * (dt * P[1][1] * P[0][1] - P[1][0] + Q_angle);
    P[0][1]     -= dt * P[1][1];
    P[1][0]     -= dt * P[1][1];
    P[1][1]     += dt * Q_gyroBias;
    //difference between the predicted angle and the accelerometer angle
    y            = newAngle - angle;
    //estimation error
    S            = P[0][0] + R_angle;
    //determine the kalman gain according to the error covariance and the distrust
    K[0]         = P[0][0]/S;
    K[1]         = P[1][0]/S;
    //adjust the angle according to the kalman gain and the difference with the measurement
    angle       += K[0] * y;
    bias        += K[1] * y;
    //update the error covariance
    P[0][0]     -= K[0] * P[0][0];
    P[0][1]     -= K[0] * P[0][1];
    P[1][0]     -= K[1] * P[0][0];
    P[1][1]     -= K[1] * P[0][1];

    return angle;
}
void ANGLE::kalman::setAngle(double newAngle) { angle = newAngle; };
void ANGLE::kalman::setQangle(double newQ_angle) { Q_angle = newQ_angle; };
void ANGLE::kalman::setQgyroBias(double newQ_gyroBias) { Q_gyroBias = newQ_gyroBias; };
void ANGLE::kalman::setRangle(double newR_angle) { R_angle = newR_angle; };

double ANGLE::kalman::getRate(void) { return rate; };
double ANGLE::kalman::getQangle(void) { return Q_angle; };
double ANGLE::kalman::getQbias(void) { return Q_gyroBias; };
double ANGLE::kalman::getRangle(void) { return R_angle; };