File content as of revision 4:809b9c3a1739:

#include "mbed.h"
#include "DHT.h"
#include "DS1820.h"

#define   DHT_DATA_PIN  D4
#define   DHT_DATA_PIN  D5


DS1820      ds1820_1(D3);  // substitute D8 with the actual pin name connected to the DS1820 sensor
DS1820      ds1820_2(D6);
float       temp1 = 0;
float       temp2 = 0;
int         result = 0;

DHT sensor1(DHT_DATA_PIN, DHT22);                    //DHT(PinName pin, eType DHTtype)
DHT sensor2(DHT_DATA_PIN, DHT22);                    //DHT(PinName pin, eType DHTtype)
HX711 loadcell(D12, D11);

Serial pc(USBTX, USBRX); // tx, rx
Serial device(D1, D0); // tx, rx

int main()
{
    int error = 0;
    float h = 0.0f, c = 0.0f;
    pc.baud(9600);
    device.baud(9600);
    
    if (!ds1820_1.begin()){
        pc.printf("No DS1820 sensor found!\r\n");
    }
    else{
        pc.printf("DS1820 sensor found!\r\n");
    }
    
    float valeurTare = loadcell.getValue();
    
    while(1) {
        float valeur = loadcell.getValue();
        float balance = ((double)valeur - (double)valeurTare)/21500;
        //pc.printf("Weight = %.2f\r\n", balance);
        
        ds1820_1.startConversion();   // start temperature conversion from analog to digital
        ds1820_2.startConversion();   // start temperature conversion from analog to digital
        ThisThread::sleep_for(1000);// let DS1820 complete the temperature conversion
        
        result = ds1820_1.read(temp1); // read temperature from DS1820 and perform cyclic redundancy check (CRC)
        result = ds1820_2.read(temp1);
        
        error1 = sensor1.readData();                  //read error value
        error2 = sensor2.readData();                  //read error value
            
        c_int   = sensor1.ReadTemperature(CELCIUS);
        h_int   = sensor1.ReadHumidity();
       
        c_ext   = sensor2.ReadTemperature(CELCIUS);
        h_ext   = sensor2.ReadHumidity();
        
        c_moyenne_int =(c_int + temp1 + temp2)/3;
        
        // pc.printf("temperature = %4.2f\r\n", c);  // on affiche les valeurs sur teraTerm pour debug
        //pc.printf("Humidite = %4.2f\r\n", h);
        
        
        device.printf("AT$SF=%02X%02X%02X%02X\r\n", (char) c_moyenne_int,(char) h_int, (char) c_ext, (char) h_ext,(char) balance);  // on envoie les données sur l'antenne
        wait(10.0f);
    }
}