BPI-M2+ 气象站_06_温度传感器的 arduino 库 (DS18b20)

〖香蕉派 BPI-M2+/BPI-M2 Zero/BPI-P2 Zero〗
1 
#include <OneWire.h>

// OneWire DS18S20, DS18B20, DS1822 Temperature Example
//
// http://www.pjrc.com/teensy/td_libs_OneWire.html
//
// The DallasTemperature library can do all this work for you!
// http://milesburton.com/Dallas_Temperature_Control_Library

OneWire  ds(10);  // on pin 10 (a 4.7K resistor is necessary)

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
  // because the result is a 16 bit signed integer, it should
  // be stored to an "int16_t" type, which is always 16 bits
  // even when compiled on a 32 bit processor.
  int16_t 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);
   // at lower res, the low bits are undefined, so let's zero them
   if (cfg == 0x00) raw = raw & ~7;  // 9 bit resolution, 93.75 ms
   else if (cfg == 0x20) raw = raw & ~3; // 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");
}

ds18b20库 OneWire.rar (16 KB)

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