File content as of revision 0:dca3b291558e:

#include "lib_SHT11.h"


SHT11::SHT11(PinName pin_DATA, PinName pin_SCK, float T_C_mesure) : DATA_HT(pin_DATA), SCK_HT(pin_SCK), Temps_cycle_mesure(T_C_mesure)
{
    if(Temps_cycle_mesure < 2)  Temps_cycle_mesure = 2;
    init();
}

void SHT11::start(void)
{
    DATA_HT.output();
    DATA_HT=1;
    SCK_HT=0;
//    wait_us(1);
    SCK_HT=1;
//    wait_us(1);
    DATA_HT=0;
//    wait_us(1);
    SCK_HT=0;
//    wait_us(1);
    SCK_HT=1;
//    wait_us(1);
    DATA_HT=1;
//    wait_us(1);
    SCK_HT=0;
//    wait_us(1);
    DATA_HT=0;
}

void SHT11::changer_timer_cycle(float new_Temps_cycle_mesure)
{
    if(new_Temps_cycle_mesure < 2)  Temps_cycle_mesure = 2;
    else Temps_cycle_mesure = new_Temps_cycle_mesure;
    if(etat_cycle)  desactiver();   init();
}

void SHT11::init(void)
{
//       ____________________________________________  
// DATA                                              |__
//            __   __   __   __   __   __   __   __   __
// SCK_HT   _|  |_|  |_|  |_|  |_|  |_|  |_|  |_|  |_|  |_
    unsigned char i;
    DATA_HT.output();
    DATA_HT=1;
    SCK_HT=0;
    for (i=0;i<9;i++)
    {
        SCK_HT=1;
//        wait_us(1);
        SCK_HT=0;
//        wait_us(1);
    }
        etat_sht11=0;
        etat_cycle=1;
        Timer_cycle_mesure.attach(this, &SHT11::gestion_HT, Temps_cycle_mesure);
}

void SHT11::desactiver(void)
{
        etat_cycle=0;
        Timer_cycle_mesure.detach();
}

void SHT11::demande_mesure(short octet_de_commande)
{
    unsigned int i;

    DATA_HT.output();
    for(i=0;i<8;i++)
    {              
        if ((octet_de_commande)&(0x80)) DATA_HT=1;
        else DATA_HT=0;
//        wait_us(1);
        SCK_HT=1;
//        wait_us(1);
        SCK_HT=0;
        octet_de_commande=octet_de_commande*2;
    }
    DATA_HT.input();
//    wait_us(1);
    SCK_HT=1;
//    wait_us(1);
    SCK_HT=0;
//    wait_us(1);
    DATA_HT.output();
    DATA_HT=1;
    DATA_HT.input();
}

void SHT11::mesure_T(void)
{
    start();
    demande_mesure(3);
}

void SHT11::mesure_H(void)
{
    start();
    demande_mesure(5);
}

void SHT11::calcul_Temperature_Humidite(void)
{
    Temperature_mesuree=(Temperature*0.01-40);
    Humidite_mesuree=((float)Temperature_mesuree-25.0)*(0.01+(0.00008*Humidite))-4+0.0405*Humidite-0.0000028*Humidite*Humidite;
}

void SHT11::reception_mesure_T(void)
{
    unsigned int i;
    Temperature=0;

        DATA_HT.input();
    for (i=0;i<8;i++)
    {
        SCK_HT=1;
//        wait_us(1);
        Temperature *=2;
        if (DATA_HT==1) Temperature++;
        SCK_HT=0;
//        wait_us(1);
    }
    DATA_HT.output();
    DATA_HT=0;
    SCK_HT=1;
//    wait_us(1);
    SCK_HT=0;
//    wait_us(1);
    DATA_HT.input();
    for (i=0;i<8;i++)
    {
        SCK_HT=1;
//        wait_us(1);
        Temperature *=2;
        if (DATA_HT==1) Temperature++;
        SCK_HT=0;
//        wait_us(1);
    }
    DATA_HT.output();
    DATA_HT=1;
    SCK_HT=1;
//    wait_us(1);
    SCK_HT=0;
//    wait_us(1);
}

void SHT11::reception_mesure_H(void)
{
    unsigned int i;
    Humidite=0;

        DATA_HT.input();
    for (i=0;i<8;i++)
    {
        SCK_HT=1;
//        wait_us(1);
        Humidite *=2;
        if (DATA_HT==1) Humidite++;
        SCK_HT=0;
//        wait_us(1);
    }
    DATA_HT.output();
    DATA_HT=0;
    SCK_HT=1;
//    wait_us(1);
    SCK_HT=0;
//    wait_us(1);
    DATA_HT.input();
    for (i=0;i<8;i++)
    {
        SCK_HT=1;
//        wait_us(1);
        Humidite *=2;
        if (DATA_HT==1) Humidite++;
        SCK_HT=0;
//        wait_us(1);
    }
    DATA_HT.output();
    DATA_HT=1;
    SCK_HT=1;
//    wait_us(1);
    SCK_HT=0;
//    wait_us(1);
}

void SHT11::gestion_HT(void)
{   
    switch (etat_sht11)
    {
        case 0:
        Timer_cycle_mesure.detach();
        mesure_T();
        etat_sht11=1;
        Timer_cycle_mesure.attach_us(this, &SHT11::gestion_HT, 10000);
        break;
        
        case 1:
        DATA_HT.input();
        if (DATA_HT==0)
        {
            Timer_cycle_mesure.detach();
            etat_sht11=2;
            Timer_cycle_mesure.attach_us(this, &SHT11::gestion_HT, 1);
        }
        break;
        
        case 2:
        Timer_cycle_mesure.detach();
        reception_mesure_T();
        etat_sht11=3;
        Timer_cycle_mesure.attach_us(this, &SHT11::gestion_HT, 1);
        break;
        
        case 3:
        Timer_cycle_mesure.detach();
        mesure_H();
        etat_sht11=4;
        Timer_cycle_mesure.attach_us(this, &SHT11::gestion_HT, 10000);
        break;
        
        case 4:
        DATA_HT.input();
        if (DATA_HT==0)
        {
            Timer_cycle_mesure.detach();
            etat_sht11=5;
            Timer_cycle_mesure.attach_us(this, &SHT11::gestion_HT, 1);
        }
        break;

        case 5:
        Timer_cycle_mesure.detach();
        reception_mesure_H();
        calcul_Temperature_Humidite();
        etat_sht11=0;
        Timer_cycle_mesure.attach(this, &SHT11::gestion_HT, Temps_cycle_mesure);
        break;

        default:
        etat_sht11=0;
        break;
    }
}

float SHT11::lire_T(void)
{
    return Temperature_mesuree;
}

float SHT11::lire_H(void)
{
    return Humidite_mesuree;
}

void SHT11::lire_T_H(float *pointeur_Temperature, float *pointeur_Humidite)
{
    *pointeur_Temperature = Temperature_mesuree;
    *pointeur_Humidite = Humidite_mesuree;
}