SmartWatch.ino

#include <DHT.h>
#include <LiquidCrystal.h>
#include <RtcDS1302.h>

#define DHTPIN 7          // DHT11 signal pin
#define DHTTYPE DHT11     // Define sensor type as DHT11
#define BUTTON_ENTER A0   // Enter alarm setting mode or delete alarm (long press)
#define BUTTON_SELECT A1  // Toggle between hour and minute
#define BUTTON_UP A2      // Increase hour/minute
#define BUTTON_DOWN A3    // Decrease hour/minute
#define BUTTON_CONFIRM A4 // Save alarm and exit
#define BUTTON_STOP A5    // Stop alarm
#define LED_PIN 6         // LED for alarm
#define BUZZER_PIN 13     // Buzzer for alarm

// Initialize DHT sensor
DHT dht(DHTPIN, DHTTYPE);

// Initialize LCD (RS, E, D4, D5, D6, D7)
LiquidCrystal lcd(12, 11, 5, 4, 3, 2);

// Initialize DS1302 RTC (SCLK, DAT, RST)
ThreeWire myWire(9, 8, 10); // DAT, SCLK, RST
RtcDS1302<ThreeWire> Rtc(myWire);

unsigned long readingCount = 0; // Counter for readings
bool alarmMode = false;         // Alarm setting mode
bool settingHours = true;       // True for hours, false for minutes
int alarmHour = 0;              // Alarm hour
int alarmMinute = 0;            // Alarm minute
bool alarmSet = false;          // Alarm enabled
bool alarmTriggered = false;    // Alarm active
unsigned long lastBlink = 0;    // For flickering
unsigned long enterPressStart = 0; // For long press detection
bool displayOn = true;          // For flickering in alarm mode
bool enterPressed = false;      // Track Enter button state

void setup() {
  Serial.begin(9600);     // Start Serial for debugging
  dht.begin();            // Initialize DHT sensor
  Rtc.Begin();            // Initialize RTC

  RtcDateTime setTime(__DATE__, __TIME__);  // Sets RTC to compile time 
  Rtc.SetDateTime(setTime);

  // Check if RTC is running
  if (!Rtc.GetIsRunning()) {
    Serial.println("RTC not running, starting now");
    Rtc.SetIsRunning(true);
  }

  // Initialize buttons with internal pull-ups
  pinMode(BUTTON_ENTER, INPUT_PULLUP);
  pinMode(BUTTON_SELECT, INPUT_PULLUP);
  pinMode(BUTTON_UP, INPUT_PULLUP);
  pinMode(BUTTON_DOWN, INPUT_PULLUP);
  pinMode(BUTTON_CONFIRM, INPUT_PULLUP);
  pinMode(BUTTON_STOP, INPUT_PULLUP);
  pinMode(LED_PIN, OUTPUT);
  pinMode(BUZZER_PIN, OUTPUT);
  digitalWrite(LED_PIN, LOW);
  digitalWrite(BUZZER_PIN, LOW);

  lcd.begin(16, 2);       // Initialize 16x2 LCD
}

void loop() {
  // Handle Enter button (short and long press)
  if (digitalRead(BUTTON_ENTER) == LOW && !enterPressed) {
    delay(50); // Debounce
    if (digitalRead(BUTTON_ENTER) == LOW) {
      enterPressed = true;
      enterPressStart = millis();
      Serial.println("Enter button pressed");
    }
  } else if (digitalRead(BUTTON_ENTER) == HIGH && enterPressed) {
    if (millis() - enterPressStart < 5000 && !alarmMode) {
      // Short press: Enter alarm setting mode
      alarmMode = true;
      settingHours = true;
      alarmHour = Rtc.GetDateTime().Hour();
      alarmMinute = Rtc.GetDateTime().Minute();
      Serial.println("Entered alarm setting mode");
    }
    enterPressed = false;
    enterPressStart = 0;
  } else if (enterPressed && millis() - enterPressStart >= 5000) {
    // Long press: Delete alarm
    alarmSet = false;
    alarmTriggered = false;
    digitalWrite(LED_PIN, LOW);
    digitalWrite(BUZZER_PIN, LOW);
    lcd.clear();
    lcd.setCursor(0, 0);
    lcd.print("T:");
    lcd.print(dht.readTemperature(), 1);
    lcd.print("C H:");
    lcd.print(dht.readHumidity(), 1);
    lcd.print("%");
    lcd.setCursor(0, 1);
    lcd.print("Alarm Deleted");
    Serial.println("Alarm deleted");
    delay(2000); // Show message for 2 seconds
    enterPressed = false;
    enterPressStart = 0;
  }

  // Handle alarm setting
  if (alarmMode) {
    if (digitalRead(BUTTON_SELECT) == LOW) {
      delay(50); // Debounce
      if (digitalRead(BUTTON_SELECT) == LOW) {
        settingHours = !settingHours;
        Serial.println(settingHours ? "Setting hours" : "Setting minutes");
        while (digitalRead(BUTTON_SELECT) == LOW); // Wait for release
      }
    }

    if (digitalRead(BUTTON_UP) == LOW) {
      delay(50); // Debounce
      if (digitalRead(BUTTON_UP) == LOW) {
        if (settingHours) {
          alarmHour = (alarmHour + 1) % 24;
        } else {
          alarmMinute = (alarmMinute + 1) % 60;
        }
        Serial.print("Alarm time: ");
        Serial.print(alarmHour);
        Serial.print(":");
        Serial.println(alarmMinute);
        while (digitalRead(BUTTON_UP) == LOW); // Wait for release
      }
    }

    if (digitalRead(BUTTON_DOWN) == LOW) {
      delay(50); // Debounce
      if (digitalRead(BUTTON_DOWN) == LOW) {
        if (settingHours) {
          alarmHour = (alarmHour - 1 + 24) % 24;
        } else {
          alarmMinute = (alarmMinute - 1 + 60) % 60;
        }
        Serial.print("Alarm time: ");
        Serial.print(alarmHour);
        Serial.print(":");
        Serial.println(alarmMinute);
        while (digitalRead(BUTTON_DOWN) == LOW); // Wait for release
      }
    }

    if (digitalRead(BUTTON_CONFIRM) == LOW) {
      delay(50); // Debounce
      if (digitalRead(BUTTON_CONFIRM) == LOW) {
        alarmMode = false;
        alarmSet = true;
        Serial.print("Alarm set to: ");
        Serial.print(alarmHour);
        Serial.print(":");
        Serial.println(alarmMinute);
        while (digitalRead(BUTTON_CONFIRM) == LOW); // Wait for release
      }
    }
  }

  // Read DHT11
  float humidity = dht.readHumidity();
  float temperature = dht.readTemperature();

  // Read RTC
  RtcDateTime now = Rtc.GetDateTime();

  // Check if DHT readings failed
  if (isnan(humidity) || isnan(temperature)) {
    Serial.println("Failed to read from DHT sensor!");
    lcd.clear();
    lcd.setCursor(0, 0);
    lcd.print("Sensor Error!");
    lcd.setCursor(0, 1);
    lcd.print("Check DHT11!");
    return;
  }

  // Check if RTC time is valid
  if (!now.IsValid()) {
    Serial.println("RTC time invalid!");
    lcd.clear();
    lcd.setCursor(0, 0);
    lcd.print("RTC Error!");
    return;
  }

  // Check if alarm should trigger
  if (alarmSet && !alarmMode && now.Hour() == alarmHour && now.Minute() == alarmMinute && now.Second() == 0) {
    alarmTriggered = true;
  }

  // Handle alarm triggering
  if (alarmTriggered) {
    if (digitalRead(BUTTON_STOP) == LOW) {
      delay(50); // Debounce
      if (digitalRead(BUTTON_STOP) == LOW) {
        alarmTriggered = false;
        digitalWrite(LED_PIN, LOW);
        digitalWrite(BUZZER_PIN, LOW);
        Serial.println("Alarm stopped");
        while (digitalRead(BUTTON_STOP) == LOW); // Wait for release
      }
    } else {
      // Flicker LED and buzzer
      if (millis() - lastBlink >= 500) {
        digitalWrite(LED_PIN, !digitalRead(LED_PIN));
        digitalWrite(BUZZER_PIN, !digitalRead(BUZZER_PIN));
        lastBlink = millis();
      }
    }
  }

  // Print to Serial Monitor
  Serial.print("Reading #");
  Serial.print(readingCount);
  Serial.print(" | Temp: ");
  Serial.print(temperature);
  Serial.print(" °C | Hum: ");
  Serial.print(humidity);
  Serial.print(" % | Date: ");
  printDateTime(now);
  Serial.println();

  // Display on LCD
  lcd.clear();
  lcd.setCursor(0, 0);    // First row: Temp and Humidity
  lcd.print("T:");
  lcd.print(temperature, 1);
  lcd.print("C H:");
  lcd.print(humidity, 1);
  lcd.print("%");

  lcd.setCursor(0, 1);    // Second row
  if (alarmMode) {
    // Flicker hours or minutes
    if (millis() - lastBlink >= 500) {
      displayOn = !displayOn;
      lastBlink = millis();
    }
    char datestring[16];
    snprintf_P(datestring, sizeof(datestring), PSTR("Set Alarm:%02u:%02u"), alarmHour, alarmMinute);
    if (displayOn || (!settingHours && !displayOn)) {
      lcd.print(datestring);
    } else {
      lcd.print("Set Alarm:  :"); // Blank hours
      lcd.setCursor(13, 1);
      lcd.print(alarmMinute < 10 ? "0" : "");
      lcd.print(alarmMinute);
    }
  } else if (alarmTriggered) {
    lcd.print("Alarm!");
  } else {
    printDateTimeLCD(now);
  }

  readingCount++;         // Increment reading counter
  delay(100);             // Short delay for responsive buttons
}

// Function to print date/time to Serial Monitor (full format)
void printDateTime(const RtcDateTime& dt) {
  char datestring[20];
  snprintf_P(datestring, 
             sizeof(datestring),
             PSTR("%04u-%02u-%02u %02u:%02u:%02u"),
             dt.Year(), dt.Month(), dt.Day(),
             dt.Hour(), dt.Minute(), dt.Second());
  Serial.print(datestring);
}

// Function to print compact date/time to LCD (DD/MM/YY HH:MM)
void printDateTimeLCD(const RtcDateTime& dt) {
  char datestring[16];
  snprintf_P(datestring, 
             sizeof(datestring),
             PSTR("%02u/%02u/%02u %02u:%02u"),
             dt.Day(), dt.Month(), dt.Year() % 100, dt.Hour(), dt.Minute());
  lcd.print(datestring);
}