#include
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)) { ds.reset_search (); delay (250); 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
for (i = 0; i < 9; i++) { // we need 9 bytes data[i] = ds.read (); }
// 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 (“ C,»); Serial.print (fahrenheit); Serial.println (“ F»); }
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