Charles ThompsonCody Hitchens
Published

House Temperature Warning

This project sends a notification if your home falls below a set temperature or rises above another set temperature.

Beginner6 hours1,116
House Temperature Warning

Things used in this project

Hardware components

Photon
Particle Photon
×2
Temperature Sensor
Temperature Sensor
×1
Resistor 10k ohm
Resistor 10k ohm
×1
Jumper wires (generic)
Jumper wires (generic)
×1
Breadboard (generic)
Breadboard (generic)
×2

Software apps and online services

Maker service
IFTTT Maker service

Story

Read more

Schematics

Temperature Sensor Schematic

This is the layout of the Particle Photon that reads the temperature.

Temperature Over Time Graph

This is a graph of our house temperature readings over a short period of time.

Temperature Reading Particle

This is a picture of the particle set up to read the temperature and publish events.

Notification Particle

This is the particle that has a code to notify the homeowner of a temperature fluctuation with an led lighting and a text message.

Code

Temperature Sensor

C/C++
This code is for the particle photon with the temperature sensor. It reads the current temperature and publishes it as an event. It will also publish a broken heater event if the temperature falls below 20 degrees Celsius. A broken AC event will be published if the temperature rises above 30 degrees Celsius.
// This #include statement was automatically added by the Particle IDE.
#include "OneWire/OneWire.h"

/************************************************************************
This sketch reads the temperature from a 1-Wire device and then publishes
to the Particle cloud. From there, IFTTT can be used to log the date,
time, and temperature to a Google Spreadsheet. Read more in our tutorial
here: http://docs.particle.io/tutorials/topics/maker-kit

This sketch is the same as the example from the OneWire library, but
with the addition of three lines at the end to publish the data to the
cloud.

Use this sketch to read the temperature from 1-Wire devices
you have attached to your Particle device (core, p0, p1, photon, electron)

Temperature is read from: DS18S20, DS18B20, DS1822, DS2438

Expanding on the enumeration process in the address scanner, this example
reads the temperature and outputs it from known device types as it scans.

I/O setup:
These made it easy to just 'plug in' my 18B20 (note that a bare TO-92
sensor may read higher than it should if it's right next to the Photon)

D3 - 1-wire ground, or just use regular pin and comment out below.
D4 - 1-wire signal, 2K-10K resistor to D5 (3v3)
D5 - 1-wire power, ditto ground comment.

A pull-up resistor is required on the signal line. The spec calls for a 4.7K.
I have used 1K-10K depending on the bus configuration and what I had out on the
bench. If you are powering the device, they all work. If you are using parisidic
power it gets more picky about the value.
************************************************************************/

OneWire ds = OneWire(D4);  // 1-wire signal on pin D4

unsigned long lastUpdate = 0;

float lastTemp;

void setup() {
  Serial.begin(9600);
  // Set up 'power' pins, comment out if not used!
  pinMode(D3, OUTPUT);
  pinMode(D5, OUTPUT);
  digitalWrite(D3, LOW);
  digitalWrite(D5, HIGH);
  
}

// up to here, it is the same as the address acanner
// we need a few more variables for this example

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;
  }

  // The order is changed a bit in this example
  // first the returned address is printed

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

  // second the CRC is checked, on fail,
  // print error and just return to try again

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

  // we have a good address at this point
  // what kind of chip do we have?
  // we will set a type_s value for known types or just return

  // the first ROM byte indicates which chip
  switch (addr[0]) {
    case 0x10:
      Serial.println("  Chip = DS1820/DS18S20");
      type_s = 1;
      break;
    case 0x28:
      Serial.println("  Chip = DS18B20");
      type_s = 0;
      break;
    case 0x22:
      Serial.println("  Chip = DS1822");
      type_s = 0;
      break;
    case 0x26:
      Serial.println("  Chip = DS2438");
      type_s = 2;
      break;
    default:
      Serial.println("Unknown device type.");
      return;
  }

  // this device has temp so let's read it

  ds.reset();               // first clear the 1-wire bus
  ds.select(addr);          // now select the device we just found
  // ds.write(0x44, 1);     // tell it to start a conversion, with parasite power on at the end
  ds.write(0x44, 0);        // or start conversion in powered mode (bus finishes low)

  // just wait a second while the conversion takes place
  // different chips have different conversion times, check the specs, 1 sec is worse case + 250ms
  // you could also communicate with other devices if you like but you would need
  // to already know their address to select them.

  delay(1000);     // maybe 750ms is enough, maybe not, wait 1 sec for conversion

  // we might do a ds.depower() (parasite) here, but the reset will take care of it.

  // first make sure current values are in the scratch pad

  present = ds.reset();
  ds.select(addr);
  ds.write(0xB8,0);         // Recall Memory 0
  ds.write(0x00,0);         // Recall Memory 0

  // now read the scratch pad

  present = ds.reset();
  ds.select(addr);
  ds.write(0xBE,0);         // Read Scratchpad
  if (type_s == 2) {
    ds.write(0x00,0);       // The DS2438 needs a page# to read
  }

  // transfer and print the values

  Serial.print("  Data = ");
  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();

  // 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 == 2) raw = (data[2] << 8) | data[1];
  byte cfg = (data[4] & 0x60);

  switch (type_s) {
    case 1:
      raw = raw << 3; // 9 bit resolution default
      if (data[7] == 0x10) {
        // "count remain" gives full 12 bit resolution
        raw = (raw & 0xFFF0) + 12 - data[6];
      }
      celsius = (float)raw * 0.0625;
      break;
    case 0:
      // 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
      if (cfg == 0x20) raw = raw & ~3; // 10 bit res, 187.5 ms
      if (cfg == 0x40) raw = raw & ~1; // 11 bit res, 375 ms
      // default is 12 bit resolution, 750 ms conversion time
      celsius = (float)raw * 0.0625;
      break;

    case 2:
      data[1] = (data[1] >> 3) & 0x1f;
      if (data[2] > 127) {
        celsius = (float)data[2] - ((float)data[1] * .03125);
      }else{
        celsius = (float)data[2] + ((float)data[1] * .03125);
      }
  }

  // remove random errors
  if((((celsius <= 0 && celsius > -1) && lastTemp > 5)) || celsius > 125) {
      celsius = lastTemp;
  }

  fahrenheit = celsius * 1.8 + 32.0;
  lastTemp = celsius;
  Serial.print("  Temperature = ");
  Serial.print(celsius);
  Serial.print(" Celsius, ");
  Serial.print(fahrenheit);
  Serial.println(" Fahrenheit");
  
  if(lastTemp < 20) {
      String temperature = String(fahrenheit);
      Particle.publish("The_House_Heater_Is_Broke3171", temperature);
      delay(1200000);  // 20 minute delay
  }

if(lastTemp > 30) {
      String temperature = String(fahrenheit);
      Particle.publish("The_House_AC_Is_Broke3171", temperature);
      delay(1200000);  // 20 minute delay
  }

  // now that we have the readings, we can publish them to the cloud
  String temperature = String(fahrenheit); // store temp in "temperature" string
  Particle.publish("Current Temperature", temperature); // publish to cloud
  delay(1200000); // 20 minute delay
 
}
 

LED

C/C++
This code is for the photon that illuminates the LED. It illuminates the LED when the broken heater event or broken AC event publish from the other photon.
int led = D7;

void setup()
{
    pinMode(led,OUTPUT);
    digitalWrite(led,LOW);
 Particle.subscribe("The_House_Heater_Is_Broke3171", temperature, "220038000847353138383138");
 Particle.subscribe("The_House_AC_Is_Broke3171", temperature, "220038000847353138383138");
}

void temperature(const char *event, const char *data)
{

      if ("The_House_Heater_Is_Broke3171")
digitalWrite(led,HIGH);
    else 
    digitalWrite(led,LOW);
    
     if ("The_House_AC_Is_Broke3171")
digitalWrite(led,HIGH);
    else 
    digitalWrite(led,LOW);
    
    
}

Credits

Charles Thompson

Charles Thompson

1 project • 2 followers
Cody Hitchens

Cody Hitchens

1 project • 1 follower

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