File content as of revision 4:05d5aa4d3f2d:

/* defines the axis for acc */
#define ACC_NOOF_AXIS       3
#define GYR_NOOF_AXIS       2
 
/* bmi160 slave address */
//DigitalOut BMX_ADDR(P1_10);
#define BMI160_ADDR         ((0x69)<<1)
 
#define RAD_DEG           57.29577951
 
//Serial pc(USBTX, USBRX); // tx, rx
 
I2C bmx(p13, p15);

int16_t acc_sample_buffer[ACC_NOOF_AXIS] = {0x5555, 0x5555, 0x5555};
int16_t gyr_sample_buffer[GYR_NOOF_AXIS] = {0x5555, 0x5555};
 
double acc_result_buffer[ACC_NOOF_AXIS] = {0x5555, 0x5555, 0x5555};
double gyr_result_buffer[GYR_NOOF_AXIS] = {0x5555, 0x5555};
 
double accel_ang_x, accel_ang_y;
double tiltx, tilty;
double tiltx_prev, tilty_prev;
 
char i2c_reg_buffer[2] = {0};

void bmx_config(){
    
    bmx.frequency(20000);
    
    /*Reset BMX160*/
    i2c_reg_buffer[0] = 0x7E;
    i2c_reg_buffer[1] = 0xB6;    
    bmx.write(BMI160_ADDR, i2c_reg_buffer, sizeof(i2c_reg_buffer), false);
    wait_ms(200);
    printf("BMX160 Resetado\n\r");
    
    /*Habilita o Acelerometro*/
    i2c_reg_buffer[0] = 0x7E;
    i2c_reg_buffer[1] = 0x11; //PMU Normal   
    bmx.write(BMI160_ADDR, i2c_reg_buffer, sizeof(i2c_reg_buffer), false);
    printf("Acc Habilitado\n\r");
    
    /*Habilita o Giroscopio*/
    i2c_reg_buffer[0] = 0x7E;
    i2c_reg_buffer[1] = 0x15;  //PMU Normal 
    bmx.write(BMI160_ADDR, i2c_reg_buffer, sizeof(i2c_reg_buffer), false);
    printf("Gyr Habilitado\n\r");
    
    /*Config o Data Rate ACC em 1600Hz*/
    i2c_reg_buffer[0] = 0x40;
    i2c_reg_buffer[1] = 0x2C;    
    bmx.write(BMI160_ADDR, i2c_reg_buffer, sizeof(i2c_reg_buffer), false);
    printf("Data Rate ACC Selecionado a 1600Hz\n\r");
    
    /*Config o Data Rate GYR em 1600Hz*/
    i2c_reg_buffer[0] = 0x42;
    i2c_reg_buffer[1] = 0x2C;    
    bmx.write(BMI160_ADDR, i2c_reg_buffer, sizeof(i2c_reg_buffer), false);
    printf("Data Rate GYR Selecionado a 1600Hz\n\r");
    
    /*Config o Range GYR em 250º/s*/
    i2c_reg_buffer[0] = 0x43;
    i2c_reg_buffer[1] = 0x03;    
    bmx.write(BMI160_ADDR, i2c_reg_buffer, sizeof(i2c_reg_buffer), false);
    printf("Range GYR Selecionado a 250deg/s\n\r");
    
}
void bmx_read(){

        i2c_reg_buffer[0] = 0x12;
        bmx.write(BMI160_ADDR, i2c_reg_buffer, 1, true);
        bmx.read(BMI160_ADDR, (char *)&acc_sample_buffer, sizeof(acc_sample_buffer), false);
        
        /*Le os Registradores do Giroscopio*/
        i2c_reg_buffer[0] = 0x0C;
        bmx.write(BMI160_ADDR, i2c_reg_buffer, 1, true);
        bmx.read(BMI160_ADDR, (char *)&gyr_sample_buffer, sizeof(gyr_sample_buffer), false);
        
        /*Ajusta dados brutos Acelerometro em unidades de g */
        acc_result_buffer[0] = (acc_sample_buffer[0]/16384.0);
        acc_result_buffer[1] = (acc_sample_buffer[1]/16384.0);
        acc_result_buffer[2] = (acc_sample_buffer[2]/16384.0);
        
        /*Ajusta dados Brutos do Giroscopio em unidades de deg/s */
        gyr_result_buffer[0] = (gyr_sample_buffer[0]/131.2);
        gyr_result_buffer[1] = (gyr_sample_buffer[1]/131.2);
                
        /*Calcula os Angulos de Inclinacao com valor do Acelerometro*/
        accel_ang_x=atan(acc_result_buffer[0]/sqrt(pow(acc_result_buffer[1],2) + pow(acc_result_buffer[2],2)))*RAD_DEG;
        accel_ang_y=atan(acc_result_buffer[1]/sqrt(pow(acc_result_buffer[0],2) + pow(acc_result_buffer[2],2)))*RAD_DEG;
        
        /*Calcula os Angulos de Rotacao com valor do Giroscopio e aplica filtro complementar realizando a fusao*/
        tiltx = (0.98*(tiltx_prev+(gyr_result_buffer[0]*0.001)))+(0.02*(accel_ang_x));
        tilty = (0.98*(tilty_prev+(gyr_result_buffer[1]*0.001)))+(0.02*(accel_ang_y));
        
        tiltx_prev = tiltx;
        tilty_prev = tilty;                                 
        
        /*Imprime os dados ACC pre-formatados*/
        printf("giro = %.3f,%.3f\n\r",tiltx, tilty);
        
}

void bmx_sleep(){
    
    i2c_reg_buffer[0] = 0x7E;
    i2c_reg_buffer[1] = 0x19;    
    bmx.write(BMI160_ADDR, i2c_reg_buffer, sizeof(i2c_reg_buffer), false);
    
    wait_ms (1);
    
    i2c_reg_buffer[0] = 0x4C;
    i2c_reg_buffer[1] = 0x80; 
    bmx.write(BMI160_ADDR, i2c_reg_buffer, sizeof(i2c_reg_buffer), false);
    
    i2c_reg_buffer[0] = 0x4F;
    i2c_reg_buffer[1] = 0x00;
    bmx.write(BMI160_ADDR, i2c_reg_buffer, sizeof(i2c_reg_buffer), false);
    
    i2c_reg_buffer[0] = 0x4E;
    i2c_reg_buffer[1] = 0x4B;
    bmx.write(BMI160_ADDR, i2c_reg_buffer, sizeof(i2c_reg_buffer), false);
    
    i2c_reg_buffer[0] = 0x7;
    i2c_reg_buffer[1] = 0x18;
    bmx.write(BMI160_ADDR, i2c_reg_buffer, sizeof(i2c_reg_buffer), false);
    
    
    }
    
void bmx_wake(){
    
    bmx_config();
        
}