DS18B20 - working on 4 separate pins D0 to D3


#1

I posted a question regarding the DS18B20 digital temperature sensor a while back and wanted to share what worked for me. I didn’t want to daisy-chain multiple sensors on a single bus due to complexities with figuring out which address belonged to which chip on the bus. I had previously been having trouble getting consistently accurate readings. This code, while perhaps not the most elegant, is working reliably.

#include <DS18B20.h>
const int MAXRETRY  =   5           ;
int     delayTime   =   16000       ; 
String sout         = "                                          ";
String tempData     = "                                          ";

float temp_Supply                   ;
float temp_Return1                  ;
float temp_Return2                  ;
float temp_Return3                  ;

float ToFahrenheit(float TempIn)    ;

DS18B20  Supply_obj(D0,TRUE)        ;
DS18B20 Return_obj1(D1,TRUE)        ;
DS18B20 Return_obj2(D2,TRUE)        ;
DS18B20 Return_obj3(D3,TRUE)        ;

void setup() {
    pinMode(D0, INPUT)              ;
    pinMode(D1, INPUT)              ;
    pinMode(D2, INPUT)              ;
    pinMode(D3, INPUT)              ;
}

void loop() {         
  
    int i = 0 ;    
        
    do {
        delay(1000)                                     ;
        temp_Supply    = Supply_obj.getTemperature()      ;
        temp_Supply    = ToFahrenheit(temp_Supply) ;
    } while (!Supply_obj.crcCheck() || MAXRETRY > i++) ; 
// Note above the while condition from another post mistakedly used && when || was needed
    
    i = 0 ;
    do {
        delay(1000)                                     ;
        temp_Return1    = Return_obj1.getTemperature()      ;
        temp_Return1    = ToFahrenheit(temp_Return1) ;
    } while (!Return_obj1.crcCheck() || MAXRETRY > i++) ; 
    
    i = 0 ;
        do {
        delay(1000)                                     ;
        temp_Return2    = Return_obj2.getTemperature()      ;
        temp_Return2    = ToFahrenheit(temp_Return2) ;
    } while (!Return_obj2.crcCheck() || MAXRETRY > i++) ; 
    
    i = 0 ;
        do {
        delay(1000)                                     ;
        temp_Return3    = Return_obj3.getTemperature()      ;
        temp_Return3    = ToFahrenheit(temp_Return3) ;
    } while (!Return_obj3.crcCheck() || MAXRETRY > i++) ; 

// I have omitted the output code because it's not central to the topic, but put it here

delay(delayTime)                            ; 
}

float ToFahrenheit(float TempIn) {              // Doing the conversion loacally
    float RetVal                    ;
    RetVal = ((TempIn*1.8)+32)    ;
    return RetVal                   ;
}