Hi,
I have what I think is a DS18B20 wired up sensor. It has 3 wires - Reg, Green & Yellow. Im using one of the sample sketches for this but cannot get a reading from it. I assume Yellow is Data, Green is GND and Red is +5V.
Im using the sketch below but it just keeps saying no more addresses, which I'm guessing means it cant find the sensor?
Any body able to help? I have Red going to +5V, Green at GND at Yellow on Digital Input 10
#include <OneWire.h>
OneWire ds(10); // on pin 10
void setup(void) {
Serial.begin(9600);
}
void loop(void) {
byte i;
byte present = 0;
byte type_s;
byte data[12];
byte addr[8];
float celsius, fahrenheit;
if ( !ds.search(addr)) {
Serial.println("No more addresses.");
Serial.println();
ds.reset_search();
delay(250);
return;
}
Serial.print("ROM =");
for( i = 0; i < 8; i++) {
Serial.write(' ');
Serial.print(addr*, HEX);*
-
}*
-
if (OneWire::crc8(addr, 7) != addr[7]) {*
-
Serial.println("CRC is not valid!");*
-
return;*
-
}*
-
Serial.println();*
-
// the first ROM byte indicates which chip*
-
switch (addr[0]) {*
-
case 0x10:*
-
Serial.println(" Chip = DS18S20"); // or old DS1820*
-
type_s = 1;*
-
break;*
-
case 0x28:*
-
Serial.println(" Chip = DS18B20");*
-
type_s = 0;*
-
break;*
-
case 0x22:*
-
Serial.println(" Chip = DS1822");*
-
type_s = 0;*
-
break;*
-
default:*
-
Serial.println("Device is not a DS18x20 family device.");*
-
return;*
-
}*
-
ds.reset();*
-
ds.select(addr);*
-
ds.write(0x44,1); // start conversion, with parasite power on at the end*
-
delay(1000); // maybe 750ms is enough, maybe not*
-
// we might do a ds.depower() here, but the reset will take care of it.*
-
present = ds.reset();*
-
ds.select(addr); *
-
ds.write(0xBE); // Read Scratchpad*
-
Serial.print(" Data = ");*
-
Serial.print(present,HEX);*
-
Serial.print(" ");*
-
for ( i = 0; i < 9; i++) { // we need 9 bytes*
_ data = ds.read();_
_ Serial.print(data*, HEX);
Serial.print(" ");
}
Serial.print(" CRC=");
Serial.print(OneWire::crc8(data, 8), HEX);
Serial.println();
// convert the data to actual temperature*
* unsigned int raw = (data[1] << 8) | data[0];_
if (type_s) {
_ raw = raw << 3; // 9 bit resolution default*
* if (data[7] == 0x10) {
// count remain gives full 12 bit resolution*
* raw = (raw & 0xFFF0) + 12 - data[6];
}
} else {
byte cfg = (data[4] & 0x60);
if (cfg == 0x00) raw = raw << 3; // 9 bit resolution, 93.75 ms*
* else if (cfg == 0x20) raw = raw << 2; // 10 bit res, 187.5 ms*
* else if (cfg == 0x40) raw = raw << 1; // 11 bit res, 375 ms*
* // default is 12 bit resolution, 750 ms conversion time*
* }
celsius = (float)raw / 16.0;
fahrenheit = celsius * 1.8 + 32.0;
Serial.print(" Temperature = ");
Serial.print(celsius);
Serial.print(" Celsius, ");
Serial.print(fahrenheit);
Serial.println(" Fahrenheit");
}*_