Christopher Mendez Martinez
Published © GPL3+

WiFi Switch for Home Appliances with ESP8266

Learn how the build your own WiFi switch with the ESP module and how to control any appliance of your favorite place.

IntermediateFull instructions provided3 hours9,719
WiFi Switch for Home Appliances with ESP8266

Things used in this project

Hardware components

ESP8266 ESP-01
Espressif ESP8266 ESP-01
×1

Software apps and online services

Arduino IDE
Arduino IDE

Story

Read more

Schematics

Schematics

Diagram and PCB's

Code

Code

Processing
/****************************************

 * Libraries

 ****************************************/

#include "UbidotsESPMQTT.h"


/****************************************

 * Define constants
 
 ****************************************/

#define TOKEN "............................" // Your Ubidots TOKEN

#define WIFINAME ".........." //Your SSID

#define WIFIPASS ".........." // Your Wifi Pass

#define DEVICE_LABEL "wifiswitch"   // Name of the device

#define VARIABLE_LABEL1  "light"  // Name of the Ubidots variable

const int ERROR_VALUE = 65535;  // Error value 

const uint8_t NUMBER_OF_VARIABLES = 2; // Cantidad de variables a las que el programa se va a suscribir
char * variable_labels[NUMBER_OF_VARIABLES] = {"light"}; // Variables names


#define luz  0
#define boton  2

int seguro=0;

int ledState = LOW;         // the current state of the output pin
int buttonState;             // the current reading from the input pin
int lastButtonState = HIGH;   // the previous reading from the input pin
int reading;
unsigned long lastDebounceTime = 0;  // the last time the output pin was toggled
unsigned long debounceDelay = 50; 

float estadoluz; // Variable to be used in the code

float value; // Variable to store input data
uint8_t variable; // To use with the switch case

Ubidots ubiClient(TOKEN);

WiFiClient client;

/****************************************

 * Auxiliar functions

 ****************************************/

void callback(char* topic, byte* payload, unsigned int length) {
  char* variable_label = (char *) malloc(sizeof(char) * 30);
  get_variable_label_topic(topic, variable_label);
  value = btof(payload, length);
  set_state(variable_label);
  execute_cases();
  free(variable_label);
  /////////////////Light////////////////////

  digitalWrite(luz, estadoluz);
 
  /////////////////Light////////////////////
  
}

// Parse topic to extract the variable label which changed value
void get_variable_label_topic(char * topic, char * variable_label) {
  Serial.print("topic:");
  Serial.println(topic);
  sprintf(variable_label, "");
  for (int i = 0; i < NUMBER_OF_VARIABLES; i++) {
    char * result_lv = strstr(topic, variable_labels[i]);
    if (result_lv != NULL) {
      uint8_t len = strlen(result_lv);      
      char result[100];
      uint8_t i = 0;
      for (i = 0; i < len - 3; i++) { 
        result[i] = result_lv[i];
      }
      result[i] = '\0';
      Serial.print("Label is: ");
      Serial.println(result);
      sprintf(variable_label, "%s", result);
      break;
    }
  }
}

// cast from an array of chars to float value.
float btof(byte * payload, unsigned int length) {
  char * demo = (char *) malloc(sizeof(char) * 10);
  for (int i = 0; i < length; i++) {
    demo[i] = payload[i];
  }
  float value = atof(demo);
  free(demo);
  return value;
}

// State machine to use switch case
void set_state(char* variable_label) {
  variable = 0;
  for (uint8_t i = 0; i < NUMBER_OF_VARIABLES; i++) {
    if (strcmp(variable_label, variable_labels[i]) == 0) {
      break;
    }
    variable++;
  }
  if (variable >= NUMBER_OF_VARIABLES) variable = ERROR_VALUE; // Not valid
  
}

// Function with switch case to determine which variable changed and assigned the value accordingly to the code variable
void execute_cases() {  
  switch (variable) {
    case 0:
      estadoluz = value;
      Serial.print("Luz: ");
      Serial.println(estadoluz);
      Serial.println();
      break;
    case ERROR_VALUE:
      Serial.println("error");
      Serial.println();
      break;
    default:
      Serial.println("default");
      Serial.println();
  }

}
/****************************************

 * Funcion principal

 ****************************************/

void setup() {

  // put your setup code here, to run once:
  pinMode(luz, OUTPUT);  
  pinMode(boton, INPUT); 
  ubiClient.ubidotsSetBroker("industrial.api.ubidots.com"); // Sets the broker properly for the business account
  ubiClient.setDebug(true); // Pass a true or false bool value to activate debug messages
  Serial.begin(115200);
  ubiClient.wifiConnection(WIFINAME, WIFIPASS);
  ubiClient.begin(callback);
  if(!ubiClient.connected()){
    ubiClient.reconnect();
  }

  char* deviceStatus = getUbidotsDevice(DEVICE_LABEL);

  if (strcmp(deviceStatus, "404") == 0) {
    ubiClient.add("light", 0); //Insert your variable Labels and the value to be sent
    ubiClient.ubidotsPublish(DEVICE_LABEL);
    ubiClient.loop();
  }

  ubiClient.ubidotsSubscribe(DEVICE_LABEL,VARIABLE_LABEL1); //Insert the Device and Variable's Labels
  Serial.println(variable_labels[1]);

}

void loop() {
  // put your main code here, to run repeatedly:
  if(!ubiClient.connected()){
    ubiClient.reconnect();
    ubiClient.ubidotsSubscribe(DEVICE_LABEL,VARIABLE_LABEL1); //Insert the Device and Variable's Labels
  }
  ubiClient.loop();    
  
  Read();

  Debounce();

  // save the reading. Next time through the loop, it'll be the lastButtonState:
  lastButtonState = reading;
          
}

void Read(){
  // read the state of the switch into a local variable:
  reading = digitalRead(boton);
  if (reading != lastButtonState) {
    // reset the debouncing timer
    lastDebounceTime = millis();
  }
}

void Debounce(){
  if ((millis() - lastDebounceTime) > debounceDelay) {
    // whatever the reading is at, it's been there for longer than the debounce
    // delay, so take it as the actual current state:

    // if the button state has changed:
    if (reading != buttonState) {
      buttonState = reading;
      Toggle();
      
    }
  }
}

void Toggle(){
  // only toggle the LED if the new button state is LOW
  if (buttonState == LOW) {
    ledState = !ledState;
    // set the LED:
    digitalWrite(luz, ledState);
    ubiClient.add("light", ledState); //Insert your variable Labels and the value to be sent
    ubiClient.ubidotsPublish(DEVICE_LABEL);
  }  
}

char* getUbidotsDevice(char* deviceLabel) {
  char* data = (char *) malloc(sizeof(char) * 700);
  char* response = (char *) malloc(sizeof(char) * 400);
  sprintf(data, "GET /api/v1.6/devices/%s/", deviceLabel);
  sprintf(data, "%s HTTP/1.1\r\n", data);
  sprintf(data, "%sHost: industrial.api.ubidots.com\r\nUser-Agent:wifiswitch/1.0\r\n", data);
  sprintf(data, "%sX-Auth-Token: %s\r\nConnection: close\r\n\r\n", data, TOKEN);
  char* data1 = data;
  free(data);
 
  if (client.connect("industrial.api.ubidots.com", 80)) {
    client.println(data1);
  } 
  else {
    free(data);
    return "e";
  }
  int timeout = 0;
  while(!client.available() && timeout < 5000) {
    timeout++;
    if (timeout >= 4999){
      free(data);
      return "e";
    }
    delay(1);
    }

  int i = 0;
  while (client.available()) {
    response[i++] = (char)client.read();
    if (i >= 399){
      break;
    }
  }
  char * pch;
  char * statusCode;
  int j = 0;
  pch = strtok (response, " ");
  while (pch != NULL) {
    if (j == 1 ) {
      statusCode = pch;
    }

    pch = strtok (NULL, " ");
    j++;
  }
  free(response);
  return statusCode;

}

Credits

Christopher Mendez Martinez

Christopher Mendez Martinez

35 projects • 74 followers
Electronic Engineer and Tech YouTuber who loves automation, programming and sharing his knowledge with everyone.

Comments

Related channels and tags
  • Espressif
  • Home Automation
  • Internet of Things
  • Security