BMP180.h

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#pragma once
#include "../Common.h"
#include <stdint.h>
#include <string.h>
#include <stdbool.h>
#include <stdlib.h>
#include <fcntl.h>
#include <unistd.h>
#include <errno.h>
 
extern "C"
{
    #include <linux/i2c-dev.h>
    #include <i2c/smbus.h>
}
 
#include <sys/ioctl.h>
#include <time.h>
#include <math.h>
#include "BaseComponent.h"
 
namespace RumPi
{
    //Pressure oversampling modes
    constexpr int BMP180_PRE_OSS0 = 0; // ultra low power
    constexpr int BMP180_PRE_OSS1 = 1; // standard
    constexpr int BMP180_PRE_OSS2 = 2; // high resolution
    constexpr int BMP180_PRE_OSS3 = 3; // ultra high resolution
 
    //Pressure read commands
    constexpr int BMP180_PRE_OSS0_CMD = 0x34;
    constexpr int BMP180_PRE_OSS1_CMD = 0x74;
    constexpr int BMP180_PRE_OSS2_CMD = 0xB4;
    constexpr int BMP180_PRE_OSS3_CMD = 0xF4;
 
    //Waiting times in us for reading pressure values
    constexpr int BMP180_PRE_OSS0_WAIT_US = 5000;
    constexpr int BMP180_PRE_OSS1_WAIT_US = 8000;
    constexpr int BMP180_PRE_OSS2_WAIT_US = 14000;
    constexpr int BMP180_PRE_OSS3_WAIT_US = 26000;
 
    //AC register
    constexpr int BMP180_REG_AC1_H = 0xAA;
    constexpr int BMP180_REG_AC2_H = 0xAC;
    constexpr int BMP180_REG_AC3_H = 0xAE;
    constexpr int BMP180_REG_AC4_H = 0xB0;
    constexpr int BMP180_REG_AC5_H = 0xB2;
    constexpr int BMP180_REG_AC6_H = 0xB4;
 
    //B1 register
    constexpr int BMP180_REG_B1_H = 0xB6;
 
    //B2 register
    constexpr int BMP180_REG_B2_H = 0xB8;
 
    //MB register
    constexpr int BMP180_REG_MB_H = 0xBA;
 
    //MC register
    constexpr int BMP180_REG_MC_H = 0xBC;
 
    //MD register
    constexpr int BMP180_REG_MD_H = 0xBE;
 
    //AC register
    constexpr int BMP180_CTRL = 0xF4;
 
    //Temperature register
    constexpr int BMP180_REG_TMP = 0xF6;
 
    //Pressure register
    constexpr int BMP180_REG_PRE = 0xF6;
 
    //Temperature read command
    constexpr int BMP180_TMP_READ_CMD = 0x2E;
 
    //Waiting time in us for reading temperature values
    constexpr int BMP180_TMP_READ_WAIT_US = 5000;
 
    //Average sea-level pressure in hPa
    constexpr double BMP180_SEA_LEVEL = 1013.25;
 
    //Lookup table for BMP180 register addresses
    static const int32_t BMP180RegisterTable[11][2] =
    {
        { BMP180_REG_AC1_H, 1 },
        { BMP180_REG_AC2_H, 1 },
        { BMP180_REG_AC3_H, 1 },
        { BMP180_REG_AC4_H, 0 },
        { BMP180_REG_AC5_H, 0 },
        { BMP180_REG_AC6_H, 0 },
        { BMP180_REG_B1_H, 1 },
        { BMP180_REG_B2_H, 1 },
        { BMP180_REG_MB_H, 1 },
        { BMP180_REG_MC_H, 1 },
        { BMP180_REG_MD_H, 1 }
    };
 
    class BMP180 : public BaseComponent
    {
    private:
        int myFileDescriptor;
 
        int myI2CAddress;
 
        int myOversamplingMode;
 
        char* myI2CDeviceFilePath;
 
        int32_t myAC1;
        int32_t myAC2;
        int32_t myAC3;
        int32_t myAC4;
        int32_t myAC5;
        int32_t myAC6;
        int32_t myB1;
        int32_t myB2;
        int32_t myMB;
        int32_t myMC;
        int32_t myMD;
 
        float myRecentlyCalculatedTemperatureInC;
        long myRecentlyCalculatedPressureInHPA;
        float myRecentlyCalculatedAltitudeInM;
 
        //Private functions used by calculations.
        void ReadSingleEpromFromRegister(int32_t* store, uint8_t reg, int32_t sign);
 
        void ReadEprom();
 
        int32_t ReadRawTemperature();
 
        int32_t ReadRawPressure(uint8_t oversamplingMode);
 
    public:
        BMP180(int bmpI2CAddress, const char* i2cDeviceFilePath);
 
        virtual ~BMP180();
 
        virtual void TurnOn() override;
 
        virtual void TurnOff() override;
 
        virtual std::string ToString() const override;
 
        virtual void ProcessRawValues() override;
 
        float CalculateTemperature();
 
        long CalculatePressure();
 
        float CalculateAltitude();
 
        int GetFileDescriptor() const;
 
        int GetI2CAddress() const;
 
        int GetOversamplingMode() const;
 
        char* GetI2CDeviceFilePath() const;
 
        int32_t GetAC1() const;
 
        int32_t GetAC2() const;
 
        int32_t GetAC3() const;
 
        int32_t GetAC4() const;
 
        int32_t GetAC5() const;
 
        int32_t GetAC6() const;
 
        int32_t GetB1() const;
 
        int32_t GetB2() const;
 
        int32_t GetMB() const;
 
        int32_t GetMC() const;
 
        int32_t GetMD() const;
    };
} // namespace RumPi