Published February 1, 2023

Wireless Home Automation (Control and Monitoring)

Wireless Home Automation (Control and Monitoring) Using a Nextion HMI Display

IntermediateFull instructions provided2 hours151

Story

Nowadays home automation is a trending topic among electronic enthusiasts and even the mass population. People are busy with their life challenges, so an electronic device should take care of the home instead! The majority of such devices need internet or Wi-Fi for connectivity or they don’t offer a user-friendly GUI, but I decided to design a standalone wireless monitoring/controlling unit that can be adjusted using a graphical and touch-controlled LCD display.

The device consists of a panelboard and a mainboard that communicate using 315MHz (or 433MHz) ASK transceivers. The panel side is equipped with a high-quality 4.3” capacitive-touch Nextion Display. The user can monitor the live temperature values and define the action threshold (to activate/deactivate the heater or cooler), humidity (to activate/deactivate the humidifier or dehumidifier), and ambient light (to turn ON/OFF the lights). The mainboard is equipped with 4 Relays to activate/deactivate the aforementioned loads.

To design the schematic and PCB, I used Altium Designer 23. The fast component search engine (octopart) allowed me to quickly consider components’ information and also generate the BOM. To get high-quality fabricated boards, I sent the Gerber files to PCBWay. I used the Arduino IDE to write the MCU code, so it is pretty easy to follow and understand. Designing a GUI using the Nextion tools was a pleasant experience that I will certainly follow for similar projects in the future. So let’s get started :-)

Specifications

Connectivity: Wireless ASK, 315MHz (or 433MHz)

Parameters: Temperature, Humidity, Ambient Light

Wireless Coverage: 100 to 200m (with Antennas)

Display: 4.3” Graphical, Capacitive-Touch

Input Voltage: 7.5 to 9V-DC (power adaptor connector)

References

https://www.pcbway.com/blog/technology/Wireless_Home_Automation_Control_and_Monitoring_Using_a_Nextion_HMI_Display_24d9be1d.html

Code

Code

#include "Adafruit_SHTC3.h"
#include <RH_ASK.h>
#include <SPI.h>
#include <TaskScheduler.h>


void t1Callback();
void t2Callback();
void t3Callback();


Scheduler runner;


Task t1(30, TASK_FOREVER, &t1Callback);
Task t2(500, TASK_FOREVER, &t2Callback);
Task t3(10, TASK_FOREVER, &t3Callback);


Adafruit_SHTC3 shtc3 = Adafruit_SHTC3();


#define heaterSW 12
#define coolerSW 8
#define humidSW 7
#define lightSW 5
#define lightSensor A7


int tempValue = 0, lightValue = 50, counter = 0;


sensors_event_t humidity, temp;


RH_ASK rf_driver(2000, 2, 15);


void setup() {
  shtc3.begin();
  rf_driver.init();
  runner.init();
  runner.addTask(t1);
  runner.addTask(t2);
  runner.addTask(t3);
  t1.enable();
  t2.enable();
  t3.enable();
  pinMode(heaterSW, OUTPUT);
  pinMode(coolerSW, OUTPUT);
  pinMode(humidSW, OUTPUT);
  pinMode(lightSW, OUTPUT);
  pinMode(lightSensor, INPUT);
  digitalWrite(heaterSW, LOW);
  digitalWrite(coolerSW, LOW);
  digitalWrite(humidSW, LOW);
  digitalWrite(lightSW, LOW);
}


void loop() {
  runner.execute();
}


void t1Callback() {
  //--------------------------Data Collection---------------------
  tempValue = map(analogRead(lightSensor), 0, 1023, 0, 99) + tempValue;
  counter ++;
  if (counter == 5)
  {
    lightValue = tempValue / 5;
    counter = 0;
    tempValue = 0;
    shtc3.getEvent(&humidity, &temp);
  }
}


void t2Callback() {
  //-------------------Transmitter--------------------------------
  static char trBuffer[20];
  sprintf(trBuffer, "P:%d:%d:%d#", int(round(temp.temperature)), int(round(humidity.relative_humidity)), lightValue);
  rf_driver.send((uint8_t *)trBuffer, strlen(trBuffer));
  rf_driver.waitPacketSent();
}
void t3Callback() {
  //--------------------Receiver----------------------------------
  char buf[12];
  uint8_t buflen = sizeof(buf);
  if (rf_driver.recv(buf, &buflen))
  {
    buf[buflen - 1] = 0;
    if (buf[0] == 'M')
    {
      if (buf[2] == 'W' && buf[3] == '1') {
        digitalWrite(coolerSW, LOW);
        digitalWrite(heaterSW, HIGH);
      }
      if (buf[2] == 'W' && buf[3] == '0') digitalWrite(heaterSW, LOW);
      if (buf[2] == 'C' && buf[3] == '1') {
        digitalWrite(heaterSW, LOW);
        digitalWrite(coolerSW, HIGH);
      }
      if (buf[2] == 'C' && buf[3] == '0') digitalWrite(coolerSW, LOW);


      if (buf[6] == '1') digitalWrite(humidSW, HIGH);
      if (buf[6] == '0') digitalWrite(humidSW, LOW);


      if (buf[9] == '1') digitalWrite(lightSW, HIGH);
      if (buf[9] == '0') digitalWrite(lightSW, LOW);
    }
  }
}

Credits

Hesam Moshiri

51 projects • 31 followers

https://www.youtube.com/c/MyVanitar/videos

Wireless Home Automation (Control and Monitoring)