Easy "If" Question

Hello,

I'm new to programming arduino and need some feedback.
I am working on a simple program to turn a relay on and off. I'm using a DS18B20 temp sensor and the onewire.h library.
As you can see, I've set pin 2 as an output high to a relay when the temp >x and low when the temp is <x. I've done some testing on the bench and it seems to work just fine.

Based on the code sections below, can anyone see any issues with what I am trying to accomplish?

void setup(void) {
Serial.begin(9600);
pinMode (2, OUTPUT);

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");
if (fahrenheit > 51) digitalWrite (2, HIGH);
if (fahrenheit < 48) digitalWrite (2, LOW);

You also seem to have a line missing.

Probably something along the lines of

raw=analogRead(thePinWithTheSensor);

That was just one portion of the entire code. It is basically the Dallas Semiconductor onewire library with my "IF" statement.
Here is the entire code:

#include <OneWire.h>

// OneWire DS18S20, DS18B20, DS1822 Temperature Example
//
// OneWire Arduino Library, connecting 1-wire devices (DS18S20, etc) to Teensy
//
// The DallasTemperature library can do all this work for you!
// MilesBurton.com

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

void setup(void) {
Serial.begin(9600);
pinMode (2, OUTPUT);
}

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");
    if (fahrenheit > 51) digitalWrite (2, HIGH);
    if (fahrenheit < 48) digitalWrite (2, LOW);
    }*_

If you use the code button as per Nick Gammon's "How to Use This Forum" Rules:

(data[1] << 8) | data[0];
if (type_s) {

Turns into

 (data[1] << 8) | data[0];
  if (type_s) {

See, no random emoticons in your code and it's much easier to read.