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#include "defines.h"

#include "temp_BMP085.h"

#include "i2c.h"

#include <delays.h>

#include <math.h>

static BMP085_DATA bmp085_data;

static BMP085_DATA *bmp085_data_p = &bmp085_data;

void BMP_Init() {

}

void BMP_Begin(unsigned char mode) {

    if (mode > BMP085_ULTRAHIGHRES)

        mode = BMP085_ULTRAHIGHRES;

    bmp085_data_p->oversampling = mode;

    if (BMP_Read8(0xD0) != 0x55) {

        DBG_PRINT_BMP("Error contacting BMP085!\r\n");

        return;

    }

    bmp085_data_p->ac1 = BMP_Read16(BMP085_CAL_AC1);

    bmp085_data_p->ac2 = BMP_Read16(BMP085_CAL_AC2);

    bmp085_data_p->ac3 = BMP_Read16(BMP085_CAL_AC3);

    bmp085_data_p->ac4 = BMP_Read16(BMP085_CAL_AC4);

    bmp085_data_p->ac5 = BMP_Read16(BMP085_CAL_AC5);

    bmp085_data_p->ac6 = BMP_Read16(BMP085_CAL_AC6);

    bmp085_data_p->b1 = BMP_Read16(BMP085_CAL_B1);

    bmp085_data_p->b2 = BMP_Read16(BMP085_CAL_B2);

    bmp085_data_p->mb = BMP_Read16(BMP085_CAL_MB);

    bmp085_data_p->mc = BMP_Read16(BMP085_CAL_MC);

    bmp085_data_p->md = BMP_Read16(BMP085_CAL_MD);

    DBG_PRINT_BMP("AC1 = %d\r\n", bmp085_data_p->ac1);

    DBG_PRINT_BMP("AC2 = %d\r\n", bmp085_data_p->ac2);

    DBG_PRINT_BMP("AC3 = %d\r\n", bmp085_data_p->ac3);

    DBG_PRINT_BMP("AC4 = %u\r\n", bmp085_data_p->ac4);

    DBG_PRINT_BMP("AC5 = %u\r\n", bmp085_data_p->ac5);

    DBG_PRINT_BMP("AC6 = %u\r\n", bmp085_data_p->ac6);

    DBG_PRINT_BMP("B1 = %d\r\n", bmp085_data_p->b1);

    DBG_PRINT_BMP("B2 = %d\r\n", bmp085_data_p->b2);

    DBG_PRINT_BMP("MB = %d\r\n", bmp085_data_p->mb);

    DBG_PRINT_BMP("MC = %d\r\n", bmp085_data_p->mc);

    DBG_PRINT_BMP("MD = %d\r\n", bmp085_data_p->md);

}

unsigned int BMP_Read_Raw_Temperature() {

    unsigned int ret;

    BMP_Write8(BMP085_CONTROL, BMP085_READTEMPCMD);

    Delay10KTCYx(255);

    ret = BMP_Read16(BMP085_TEMPDATA);

    DBG_PRINT_BMP("Raw Temp: %d\r\n", ret);

    return ret;

}

unsigned long BMP_Read_Raw_Pressure() {

    unsigned long ret;

    BMP_Write8(BMP085_CONTROL, BMP085_READPRESSURECMD + (bmp085_data_p->oversampling << 6));

    if (bmp085_data_p->oversampling == BMP085_ULTRALOWPOWER)

        Delay10KTCYx(255);

    else if (bmp085_data_p->oversampling == BMP085_STANDARD)

        Delay10KTCYx(255);

    else if (bmp085_data_p->oversampling == BMP085_HIGHRES)

        Delay10KTCYx(255);

    else

        Delay10KTCYx(255);

    ret = BMP_Read16(BMP085_PRESSUREDATA);

    ret <<= 8;

    ret |= BMP_Read8(BMP085_PRESSUREDATA+2);

    ret >>= (8 - bmp085_data_p->oversampling);

    DBG_PRINT_BMP("Raw Pressure: %ld\r\n", ret);

    return ret;

}

long BMP_Read_Pressure() {

    long UT, UP, B3, B5, B6, X1, X2, X3, p;

    unsigned long B4, B7;

    UT = BMP_Read_Raw_Temperature();

    UP = BMP_Read_Raw_Pressure();

    // Temperature calculations

    X1 = ((UT - (long) bmp085_data_p->ac6) * (long) bmp085_data_p->ac5) >> 15;

    X2 = ((long) bmp085_data_p->mc << 11) - (X1 + bmp085_data_p->md) / 2; // round up

    X2 /= (X1 + bmp085_data_p->md);

    B5 = X1 + X2;

    // Pressure calcs

    B6 = B5 - 4000;

    X1 = ((long) bmp085_data_p->b2 * ((B6 * B6) >> 12)) >> 11;

    X2 = ((long) bmp085_data_p->ac2 * B6) >> 11;

    X3 = X1 + X2;

    B3 = ((((long) bmp085_data_p->ac1 * 4 + X3) << bmp085_data_p->oversampling) + 2) / 4;

    X1 = ((long) bmp085_data_p->ac3 * B6) >> 13;

    X2 = ((long) bmp085_data_p->b1 * ((B6 * B6) >> 12)) >> 16;

    X3 = ((X1 + X2) + 2) >> 2;

    B4 = ((unsigned long) bmp085_data_p->ac4 * (unsigned long) (X3 + 32768)) >> 15;

    B7 = ((unsigned long) UP - B3) * (unsigned long) (50000UL >> bmp085_data_p->oversampling);

    if (B7 < 0x80000000) {

        p = (B7 * 2) / B4;

    } else {

        p = (B7 / B4) * 2;

    }

    X1 = (p >> 8) * (p >> 8);

    X1 = (X1 * 3038) >> 16;

    X2 = (-7357 * p) >> 16;

    p = p + ((X1 + X2 + (long)3791)>>4);

    return p;

}

float BMP_Read_Temperature() {

    long UT, X1, X2, B5;

    float temp;

    UT = BMP_Read_Raw_Temperature();

    X1 = ((UT - (long) bmp085_data_p->ac6) * (long) bmp085_data_p->ac5) >> 15;

    X2 = ((long) bmp085_data_p->mc << 11) / (X1 + (long) bmp085_data_p->md);

    B5 = X1 + X2;

    temp = (B5 + 8) >> 4;

    temp /= 10;

    return temp;

}

float BMP_Read_Altitude(float seaLevelPressure) {

    float altitude;

    float pressure = BMP_Read_Pressure();

    altitude = 44330 * (1.0 - pow(pressure /seaLevelPressure,0.1903));

    return altitude;

}

unsigned char BMP_Read8(unsigned char a) {

    unsigned char buffer[6], result, length, ret = 0;

    I2C_Master_Restart(BMP085_I2CADDR, a, 1);

    do {

        result = I2C_Get_Status();

    } while (!result);

    length = I2C_Read_Buffer((char *)buffer);

    ret = buffer[0];

    return ret;

}

unsigned int BMP_Read16(unsigned char a) {

    unsigned char buffer[6], result, length;

    unsigned int ret;

    I2C_Master_Restart(BMP085_I2CADDR, a, 2);

    do {

        result = I2C_Get_Status();

    } while (!result);

    length = I2C_Read_Buffer((char *)buffer);

    ret = buffer[0];

    ret <<= 8;

    ret |= buffer[1];

    return ret;

}

void BMP_Write8(unsigned char a, unsigned char d) {

    unsigned char buffer[2], result;

    buffer[0] = a;

    buffer[1] = d;

    I2C_Master_Send(BMP085_I2CADDR, 2, buffer);

    do {

        result = I2C_Get_Status();

    } while (!result);

}