[NOTE this is my old page saved for enjoyment of future generations, many links dead]

Jeff McLellan | Data Analysis & App Developer

Get Device Rom

// Use the Library feature in Particle Builder to add the OneWire library
// and this #include statement will be automatically added by the IDE
#include "OneWire/OneWire.h"

OneWire ds = OneWire(D3);  // pin used for data (a 4.7K resistor is necessary)
unsigned long lastUpdate = 0; 

void setup() {
  Serial.begin(9600);
}

void loop() {

 unsigned long now = millis();
    if((now - lastUpdate) > 3000)
    {
        lastUpdate = now;
        byte i;
        byte present = 0;
        byte addr[8];

      if ( !ds.search(addr)) {
        Serial.println("No more addresses.");
        Serial.println();
        ds.reset_search();
        //delay(250);
        return;
      }
    
      // the first ROM byte indicates which chip
      switch (addr[0]) {
        case 0x10:
          Serial.println("Chip = DS18S20");  // or old DS1820
          break;
        case 0x28:
          Serial.println("Chip = DS18B20");
          break;
        case 0x22:
          Serial.println("Chip = DS1822");
          break;
        default:
          Serial.println("Device is not a DS18x20 family device.");
          return;
      }

      Serial.print("ROM = ");
      Serial.print("0x");
        Serial.print(addr[0],HEX);
      for( i = 1; i < 8; i++) {
        Serial.print(", 0x");
        Serial.print(addr[i],HEX);
      }

      if (OneWire::crc8(addr, 7) != addr[7]) {
          Serial.println("CRC is not valid!");
          return;
      }

    Serial.println();
    ds.reset();

    }
}