Having a problem with DS18B20 getTempC using an array containing the addresses of the sensors

Question

I have been struggling with this and am at a total loss as to why its not working. Here is my program:

#include <OneWire.h>
#include <DallasTemperature.h>
// Data wire is Arduino pin A0
#define ONE_WIRE_BUS A0
// Setup a oneWire instance 
OneWire oneWire(ONE_WIRE_BUS);
// Pass our oneWire reference to Dallas Temperature.
DallasTemperature sensors(&oneWire);
// Define array for holding all the sensors addresses and load addresses.
//======================================================================
DeviceAddress SensorAddr [13] = 
 {
 ( 0x28, 0xAA, 0x30, 0x41, 0x38, 0x14, 0x01, 0x14 ), // Sensor 1
 ( 0x28, 0xAA, 0x24, 0x31, 0x38, 0x14, 0x01, 0xDF ), // Sensor 2
 ( 0x28, 0xAA, 0xE4, 0x30, 0x38, 0x14, 0x01, 0x72 ), // Sensor 3
 ( 0x28, 0xAA, 0xD4, 0xC2, 0x38, 0x14, 0x01, 0x80 ), // Sensor 4
 ( 0x28, 0xAA, 0x6C, 0xDA, 0x38, 0x14, 0x01, 0xD5 ), // Sensor 5
 ( 0x28, 0xAA, 0xCA, 0x39, 0x38, 0x14, 0x01, 0xBB ), // Sensor 6
 ( 0x28, 0xAA, 0x75, 0x28, 0x38, 0x14, 0x01, 0x2C ), // Sensor 7
 ( 0x28, 0xAA, 0xFB, 0xB2, 0x38, 0x14, 0x01, 0xBF ), // Sensor 8
 ( 0x28, 0xAA, 0x0F, 0x3A, 0x38, 0x14, 0x01, 0xC3 ), // Sensor 9
 ( 0x28, 0xAA, 0x6F, 0x26, 0x38, 0x14, 0x01, 0xF8 ), // Sensor 10
 ( 0x28, 0xFF, 0x64, 0x1E, 0x1E, 0x6A, 0x74, 0xF1 ), // Sensor 11
 ( 0x28, 0xFF, 0x64, 0x1E, 0x1E, 0x7D, 0x29, 0x55 ), // Sensor 12
 ( 0x28, 0xFF, 0x64, 0x1E, 0x1E, 0x73, 0xAC, 0x3A ) // Sensor 13
 };
 
void setup(void)
{
 Serial.begin(9600);
 sensors.begin();
 
//Test first Sensor Address - This works
//=======================================
 byte Sensor1Test[8] = { 0x28, 0xAA, 0x30, 0x41, 0x38, 0x14, 0x01, 0x14};
 Serial.print("Test Sensor 1: ");
 float tempTest = sensors.getTempC( Sensor1Test );
 Serial.print(tempTest, 2);
 Serial.print("\xC2\xB0"); // shows degree symbol
 Serial.print("C"); 
 Serial.println(); 
}
void loop(void)
// Get all temperatures - This does not work??
//============================================
{
 sensors.requestTemperatures();
 for (int S =0; S<13; S++)
 {
 Serial.print("Sensor # "); Serial.print(S+1); Serial.print(": ");
 float tempC = sensors.getTempC(SensorAddr [S]);
 Serial.print(tempC,2);
 Serial.print("\xC2\xB0"); // shows degree symbol
 Serial.print("C"); 
 Serial.println();
 delay(1000);
 }
 Serial.println();
}

This is the result

• jsotola: please, no pictures of text ... delete the picture and add the text
• DrG: Go through the tutorial at lastminuteengineers.com/multiple-ds18b20-arduino-tutorial. Try using their code for reading multiple sensors by address (or index, but you are trying to read by address). Try doing the read loop the way they are doing it and using uint8_t arrays - it can't hurt. Let us know how that goes please.
• jsotola: that is not how this site works ... please post the updated code in an answer and explain how the problem was solved ... rolled back your edit

Answer 1

The DeviceAddress internally is defined as an array of uint8_t (see definition:

typedef uint8_t DeviceAddress[8];

That is, each address is an array itself.

DeviceAddress Sensor1 = { 0x28, 0xAA, 0x30, 0x41, 0x38, 0x14, 0x01, 0x14 };

So if you have 13 DeviceAdrress, you are dealing with a two-dimension array, and you need to declare it as:

#define NUMBER_OF_SENSORS 13
DeviceAddress SensorAddr [NUMBER_OF_SENSORS] = {
 { 0x28, 0xAA, 0x30, 0x41, 0x38, 0x14, 0x01, 0x14 }, // Sensor 1
 { 0x28, 0xAA, 0x24, 0x31, 0x38, 0x14, 0x01, 0xDF }, // Sensor 2
 { 0x28, 0xAA, 0xE4, 0x30, 0x38, 0x14, 0x01, 0x72 }, // Sensor 3
 { 0x28, 0xAA, 0xD4, 0xC2, 0x38, 0x14, 0x01, 0x80 }, // Sensor 4
 { 0x28, 0xAA, 0x6C, 0xDA, 0x38, 0x14, 0x01, 0xD5 }, // Sensor 5
 { 0x28, 0xAA, 0xCA, 0x39, 0x38, 0x14, 0x01, 0xBB }, // Sensor 6
 { 0x28, 0xAA, 0x75, 0x28, 0x38, 0x14, 0x01, 0x2C }, // Sensor 7
 { 0x28, 0xAA, 0xFB, 0xB2, 0x38, 0x14, 0x01, 0xBF }, // Sensor 8
 { 0x28, 0xAA, 0x0F, 0x3A, 0x38, 0x14, 0x01, 0xC3 }, // Sensor 9
 { 0x28, 0xAA, 0x6F, 0x26, 0x38, 0x14, 0x01, 0xF8 }, // Sensor 10
 { 0x28, 0xFF, 0x64, 0x1E, 0x1E, 0x6A, 0x74, 0xF1 }, // Sensor 11
 { 0x28, 0xFF, 0x64, 0x1E, 0x1E, 0x7D, 0x29, 0x55 }, // Sensor 12
 { 0x28, 0xFF, 0x64, 0x1E, 0x1E, 0x73, 0xAC, 0x3A } // Sensor 13
};
for (int s=0; s<NUMBER_OF_SENSORS; S++) {
 float tempC = sensors.getTempC(SensorAddr[s]);
}