Wireless termometer.

recv.ino

#include <Arduino.h>
#include "nRF24L01.h"
#include "RF24.h"

int msg[2];
RF24 radio(9, 10);
const uint64_t pipe = 0xE8E8F0F0E1LL;

void setup(void) {
  Serial.begin(9600);
  radio.begin();
  radio.openReadingPipe(1, pipe);
  radio.startListening();
}

void loop(void) {
  if (radio.available()) {
    bool done = false;
    while (!done) {
      done = radio.read(msg, 4);
      int Fract = msg[0] % 100;
      Serial.print(msg[0] / 100);

      Serial.print(".");
      if (Fract < 10) Serial.print("0");
      Serial.print(Fract);
      Serial.print(" ");
      Serial.println(msg[0]);
      if (msg[0] == 111) {
        delay(10);
      }
      delay(10);
    }
  }
  else {
    delay(100);
    Serial.println("No radio available");
  }
}

send.ino

#include  <SPI.h>
#include "nRF24L01.h"
#include "RF24.h"
#include "OneWire.h"

OneWire ds(2);
int msg[2];
RF24 radio(9, 10);
const uint64_t pipe = 0xE8E8F0F0E1LL;
int SW1 = 7;

void setup(void) {
  Serial.begin(9600);
  radio.begin();
  radio.openWritingPipe(pipe);
}

void loop(void) {
  byte i;
  byte present = 0;
  byte data[12];
  byte addr[8];

  ds.reset_search();
  if (!ds.search(addr)) {
    Serial.print("No more addresses.\n");
    ds.reset_search();
    return;
  }

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

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

  if (addr[0] == 0x10) {
    Serial.print("Device is a DS18S20 family device.\n");
  }
  else if (addr[0] == 0x28) {
    Serial.print("Device is a DS18B20 family device.\n");
  }
  else {
    Serial.print("Device family is not recognized: 0x");
    Serial.println(addr[0], HEX);
    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("P=");
  Serial.print(present, HEX);
  Serial.print(" ");
  for (i = 0; i < 9; i++) {           // we need 9 bytes
    data[i] = ds.read();
    Serial.print(data[i], HEX);
    Serial.print(" ");
  }
  Serial.print(" CRC=");
  Serial.print(OneWire::crc8(data, 8), HEX);
  Serial.println();

  int HighByte, LowByte, TReading, SignBit, Tc_100, Whole, Fract;
  LowByte = data[0];
  HighByte = data[1];
  TReading = (HighByte << 8) + LowByte;
  SignBit = TReading & 0x8000;  // test most sig bit
  if (SignBit) // negative
  {
    TReading = (TReading ^ 0xffff) + 1; // 2's comp
  }
  Tc_100 = (6 * TReading) + TReading / 4;    // multiply by (100 * 0.0625) or 6.25

  Whole = Tc_100 / 100;  // separate off the whole and fractional portions
  Fract = Tc_100 % 100;


  if (SignBit) // If its negative
  {
    Serial.print("-");
  }
  Serial.print(Whole);

  Serial.print(".");
  if (Fract < 10)
  {
    Serial.print("0");
  }
  Serial.print(Fract);
  msg[0] = Tc_100;
  radio.write(msg, 4);
  Serial.print("\n");
}