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// **********************************************************************************
// Driver definition for HopeRF TH02 temperature and humidity sensor
// **********************************************************************************
// Creative Commons Attrib Share-Alike License
// You are free to use/extend this library but please abide with the CC-BY-SA license:
// http://creativecommons.org/licenses/by-sa/4.0/
//
// For any explanation see TH02 sensor information at
// http://www.hoperf.com/sensor/app/TH02.htm
//
// Code based on following datasheet
// http://www.hoperf.com/upload/sensor/TH02_V1.1.pdf
//
// Written by Charles-Henri Hallard (http://hallard.me)
//
// History : V1.00 2014-07-14 - First release
//           V1.10 2015-04-13 - changed to Wire library instead of m_I2C
//
// All text above must be included in any redistribution.
//
// **********************************************************************************
#include "th02.h"
#include "mbed.h"
#include "math.h"

// Class Constructor

TH02::TH02(PinName sda,PinName scl,uint8_t address): m_I2C(sda, scl)
{
    _address = address; // m_I2C Module Address
    _last_temp = TH02_UNINITIALIZED_TEMP;  // Last measured temperature (for linearization)
    _last_rh = TH02_UNINITIALIZED_RH;      // Last measured RH
//m_I2C.frequency(10000); //set 10khz i2c frequency

}

TH02::~TH02()
{

}



/* ======================================================================
Function: writeCommand
Purpose : write the "register address" value on m_I2C bus
Input   : register address
          true if we need to release the bus after (default yes)
Output  : Arduino Wire library return code (0 if ok)
Comments:
====================================================================== */
uint8_t TH02::writeCommand(uint8_t command, bool release)
{
    int iError;
    (void) m_I2C.start();
    //Wire.beginTransmission(_address);
    iError=m_I2C.write(_address);// send adress of i2c slave

    if (iError==1) { // ack received
// Wire.write(command) ;
        iError= m_I2C.write(command);


        if (release==true) {
            m_I2C.stop();// return stop error code
        }
    }

    if (iError==1) iError=0;// ack received
    else iError=1;// no ack
    return iError;
}

/* ======================================================================
Function: writeRegister
Purpose : write a value on the designed register address on m_I2C bus
Input   : register address
          value to write
Output  : Arduino Wire library return code (0 if ok)
Comments:
====================================================================== */
uint8_t TH02::writeRegister(uint8_t reg, uint8_t value)
{
    int iError;

    bool ret = false;

    //Wire.beginTransmission(_address);
    (void) m_I2C.start();
    iError=m_I2C.write(_address);// send adress of i2c slave
// Wire.write(reg);
    if (iError==1) {

        iError= m_I2C.write(reg);

// Wire.write(value);
        (void) m_I2C.write(value);
    }
// return Wire.endTransmission();
    m_I2C.stop();// return stop error code
    if (iError==1) iError=0;// ack received
    else iError=1;// no ack
    wait_ms(1);
    return iError;
}

/* ======================================================================
Function: readRegister
Purpose : read a register address value on m_I2C bus
Input   : register address
          pointer where the return value will be filled
Output  : Arduino Wire library return code (0 if ok)
Comments:
====================================================================== */
uint8_t TH02::readRegister(uint8_t reg, uint8_t * value)
{
    uint8_t ret ;
    int iAck,iRedVal,iError;
    // Send a register reading command
    // but DO NOT release the m_I2C bus
// (void) m_I2C.start();
    //iError=m_I2C.write(_address);// send adress of i2c slave

    //if (iError==1) // ack received
    //{
    ret = writeCommand(reg, false);// no stop

    if ( ret == 0) { //if command ok
        // Wire.requestFrom( (uint8_t) _address, (uint8_t) 1);
        (void) m_I2C.start();
        iError=m_I2C.write(_address+0x01);// send adress of i2c slave in read mode
        *value =m_I2C.read(0);//send non ack
        // if (Wire.available() != 1)
        /*if (iAck != 1)

        // Other error as Wire library
        ret = 4;
        else
        // grab the value*/
        //   *value = iRedVal; // return Red value by ref

        //}

        // Ok now we have finished
// Wire.endTransmission();

    }
    (void) m_I2C.stop();// return stop error code
    wait_ms(1);
    return ret;
}

/* ======================================================================
Function: getId
Purpose : Get device ID register
Input   : pointer where the return value will be filled
Output  : Arduino Wire library return code (0 if ok)
Comments: -
====================================================================== */
uint8_t TH02::getId(uint8_t * pvalue)
{
    return (readRegister(TH02_ID, pvalue));
}

/* ======================================================================
Function: getStatus
Purpose : Get device status register
Input   : pointer where the return value will be filled
Output  : Arduino Wire library return code (0 if ok)
Comments:
====================================================================== */
uint8_t TH02::getStatus(uint8_t * pvalue)
{
    return (readRegister(TH02_STATUS, pvalue));
}

/* ======================================================================
Function: isConverting
Purpose : Indicate if a temperature or humidity conversion is in progress
Input   : -
Output  : true if conversion in progress false otherwise
Comments:
====================================================================== */
bool TH02::isConverting(void)
{
    uint8_t status;
    // Get status and check RDY bit
    if ( getStatus(&status) == 0)

    {
       // printf("\n lecture status %x",status);
        if ( (status & TH02_STATUS_RDY) ==1 )
            return true;
    }
    return false;
}

/* ======================================================================
Function: getConfig
Purpose : Get device configuration register
Input   : pointer where the return value will be filled
Output  : Arduino Wire library return code (0 if ok)
Comments:
====================================================================== */
uint8_t TH02::getConfig(uint8_t * pvalue)
{
    return (readRegister(TH02_CONFIG, pvalue));
}

/* ======================================================================
Function: setConfig
Purpose : Set device configuration register
Input   : value to set
Output  : true if succeded, false otherwise
Comments:
====================================================================== */
uint8_t TH02::setConfig(uint8_t config)
{
    return (writeRegister(TH02_CONFIG, config));
}

/* ======================================================================
Function: startTempConv
Purpose : Start a temperature conversion
Input   : - fastmode true to enable fast conversion
          - heater true to enable heater
Output  : true if succeded, false otherwise
Comments: if heater enabled, it will not be auto disabled
====================================================================== */
uint8_t TH02::startTempConv(bool fastmode, bool heater)
{
    // init configuration register to start and temperature
    uint8_t config = TH02_CONFIG_START | TH02_CONFIG_TEMP;

    // set fast mode and heater if asked
    if (fastmode) config |= TH02_CONFIG_FAST;
    if (heater)   config |= TH02_CONFIG_HEAT;

    // write to configuration register
    return ( setConfig( config ) );
}

/* ======================================================================
Function: startRHConv
Purpose : Start a relative humidity conversion
Input   : - fastmode true to enable fast conversion
          - heater true to enable heater
Output  : true if succeded, false otherwise
Comments: if heater enabled, it will not be auto disabled
====================================================================== */
uint8_t TH02::startRHConv(bool fastmode, bool heater)
{
    // init configuration register to start and no temperature (so RH)
    uint8_t config = TH02_CONFIG_START;

    // set fast mode and heater if asked
    if (fastmode) config |= TH02_CONFIG_FAST;
    if (heater)   config |= TH02_CONFIG_HEAT;

    // write to configuration register
    return ( setConfig( config ) );
}

/* ======================================================================
Function: waitEndConversion
Purpose : wait for a temperature or RH conversion is done
Input   :
Output  : delay in ms the process took.
Comments: if return >= TH02_CONVERSION_TIME_OUT, time out occured
====================================================================== */
uint8_t TH02::waitEndConversion(void)
{
    // okay this is basic approach not so accurate
    // but avoid using long and millis()
    uint8_t time_out = 0;

    // loop until conversion done or duration >= time out
    while (isConverting() && (time_out <= TH02_CONVERSION_TIME_OUT) ) {
        ++time_out;
        wait_ms(2);
    }

    // return approx time of conversion
    return (time_out);
}

/* ======================================================================
Function: roundInt
Purpose : round a float value to int
Input   : float value
Output  : int value rounded
Comments:
====================================================================== */
int16_t TH02::roundInt(float value)
{

    // check positive number and do round
    if (value >= 0.0f)
        value = floor(value + 0.5f);
    else
        value = ceil(value - 0.5f);

    // return int value
    return (static_cast<int16_t>(value));
}

/* to avoid math library may I need to test something
   like that
float TH02::showDecimals(float x, int numDecimals)
{
    int y=x;
    double z=x-y;
    double m=pow(10,numDecimals);
    double q=z*m;
    double r=round(q);
    return static_cast<double>(y)+(1.0/m)*r;
}
*/


/* ======================================================================
Function: getConversionValue
Purpose : return the last converted value to int * 10 to have 1 digit prec.
Input   : float value
Output  : value rounded but multiplied per 10 or TH02_UNDEFINED_VALUE on err
Comments: - temperature and rh raw values (*100) are stored for raw purpose
          - the configuration register is checked to see if last conv was
            a temperature or humidity conversion
====================================================================== */
int16_t TH02::getConversionValue(void)
{
    char cMaChaine[4];
    int iError;
    int32_t result=0 ;
    uint8_t config;
    int16_t  ret = TH02_UNDEFINED_VALUE;

    // Prepare reading address of ADC data result
    /*if ( writeCommand(TH02_DATAh, false) == 0 ) // no stop
    {*/
    // Read 2 bytes adc data result MSB and LSB from TH02
    //Wire.requestFrom( (uint8_t) _address, (uint8_t) 2);
    writeCommand(TH02_DATAh, false);

    // read of two register
    (void) m_I2C.start();
    iError=m_I2C.write(_address+1);// send adress of i2c slave read mode
    if (iError==1) {
        cMaChaine[0]= m_I2C.read(1);// read first byte with ack
        cMaChaine[1]=m_I2C.read(0);// read first byte without ack
       
      m_I2C.stop();// rperform stop



        //iError= m_I2C.read (_address,cMaChaine,4,false);// send stop at end
       // printf (" \n\r lecture I2C: %02x %02x",cMaChaine[0],cMaChaine[1]);
      //}
       result=(cMaChaine[0]<<8 )|cMaChaine[1];
        // Get configuration to know what was asked last time
       
        if (getConfig(&config)==0) {
            // last conversion was temperature ?
            if( config & TH02_CONFIG_TEMP) {
                result >>= 2;  // remove 2 unused LSB bits
                result *= 100; // multiply per 100 to have int value with 2 decimal
                result /= 32;  // now apply datasheet formula
                if(result >= 5000) {
                    result -= 5000;
                } else {
                    result -= 5000;
                    result = -result;
                }

                // now result contain temperature * 100
                // so 2134 is 21.34 C

                // Save raw value
                _last_temp = result;
            }
            // it was RH conversion
            else {
                result >>= 4;  // remove 4 unused LSB bits
                result *= 100; // multiply per 100 to have int value with 2 decimal
                result /= 16;  // now apply datasheet formula
                result -= 2400;

                // now result contain humidity * 100
                // so 4567 is 45.67 % RH
                _last_rh = result;
            }

            // remember result value is multiplied by 10 to avoid float calculation later
            // so humidity of 45.6% is 456 and temp of 21.3 C is 213
        ret = roundInt(result/10.0f);
        }
     }   
     
     else{
         
      m_I2C.stop();// rperform stop
      }
    return ret;
}





/* ======================================================================
Function: getConpensatedRH
Purpose : return the compensated calulated humidity
Input   : true if we want to round value to 1 digit precision, else 2
Output  : the compensed RH value (rounded or not)
Comments:
====================================================================== */
int16_t TH02::getConpensatedRH(bool round)
{
    float rhvalue  ;
    float rhlinear ;
    int16_t  ret = TH02_UNDEFINED_VALUE;

    // did we had a previous measure RH
    if (_last_rh != TH02_UNINITIALIZED_RH) {
        // now we're float restore real value RH value
        rhvalue = (float) _last_rh / 100.0 ;

        // apply linear compensation
        rhlinear = rhvalue - ((rhvalue*rhvalue) * TH02_A2 + rhvalue * TH02_A1 + TH02_A0);

        // correct value
        rhvalue = rhlinear;

        // do we have a initialized temperature value ?
        if (_last_temp != TH02_UNINITIALIZED_TEMP ) {
            // Apply Temperature compensation
            // remember last temp was stored * 100
            rhvalue += ((_last_temp/100.0) - 30.0) * (rhlinear * TH02_Q1 + TH02_Q0);
        }

        // now get back * 100 to have int with 2 digit precision
        rhvalue *= 100;

        // do we need to round to 1 digit ?
        if (round) {
            // remember result value is multiplied by 10 to avoid float calculation later
            // so humidity of 45.6% is 456
            ret = roundInt(rhvalue/10.0f);
        } else {
            ret = (int16_t) rhvalue;
        }
    }

    return ret;
}

/* ======================================================================
Function: getLastRawRH
Purpose : return the raw humidity * 100
Input   :
Output  : int value (ie 4123 for 41.23%)
Comments:
====================================================================== */
int32_t TH02::getLastRawRH(void)
{
    return _last_rh;
}

/* ======================================================================
Function: getLastRawTemp
Purpose : return the raw temperature value * 100
Input   :
Output  : int value (ie 2124 for 21.24 C)
Comments:
====================================================================== */
int32_t TH02::getLastRawTemp(void)
{
    return _last_temp;
}