ESP32 Six-Mode Farm Monitor

#include <Arduino.h>
#include <Wire.h>
#include <RTClib.h>
#include <LiquidCrystal_I2C.h>

const int SOIL_PIN = 34;
const int TURBIDITY_PIN = 35;
const int TRIG_PIN = 18;
const int ECHO_PIN = 23;
const int ENCODER_CLK_PIN = 33;
const int ENCODER_DT_PIN = 32;
const int ENCODER_SW_PIN = 27;
const int BUZZER_PIN = 14;
const int LED_RED_PIN = 25;
const int LED_YELLOW_PIN = 26;
const int LED_GREEN_PIN = 13;
const int I2C_SDA_PIN = 21;
const int I2C_SCL_PIN = 22;

// Sesuaikan tiga nilai ini setelah kalibrasi dengan tanah benar-benar kering dan basah.
const int SOIL_DRY_RAW = 3600;
const int SOIL_WET_RAW = 1800;
const float TANK_REFERENCE_HEIGHT_CM = 20.0f;
const int RTC_ALARM_HOUR = 7;
const int RTC_ALARM_MINUTE = 0;

RTC_DS3231 rtc;
LiquidCrystal_I2C lcd(0x27, 16, 2);
bool rtcReady = false;
char lastLcdLine0[17] = "";
char lastLcdLine1[17] = "";
// mode adalah pilihan yang terlihat di LCD; activeMode baru berjalan setelah tombol encoder ditekan.
int mode = 1;
int activeMode = 0;
int lastEncoderClk = HIGH;
int lastButtonState = HIGH;
unsigned long lastButtonChangeMs = 0;
unsigned long lastSoilReadMs = 0;
unsigned long lastWaterReadMs = 0;
unsigned long lastTurbidityReadMs = 0;
unsigned long lastRtcReadMs = 0;
unsigned long mode4LightUntilMs = 0;
unsigned long rtcAlarmUntilMs = 0;
uint32_t rtcAlarmDateKey = 0;
float soilPercent = 0.0f;
float waterHeightCm = -1.0f;
float turbidityNtuEstimate = 0.0f;
int mode4LastBand = -1;
bool buzzerOn = false;
// Mode 5: tekan sekali untuk atur jam, tekan lagi untuk menit, lalu tekan lagi untuk simpan.
uint8_t rtcSettingStage = 0; // 0=normal, 1=atur jam, 2=atur menit
int rtcSetHour = 0;
int rtcSetMinute = 0;

void allLedsOff() {
  digitalWrite(LED_RED_PIN, LOW);
  digitalWrite(LED_YELLOW_PIN, LOW);
  digitalWrite(LED_GREEN_PIN, LOW);
}

void setBuzzer(bool on) {
  if (on == buzzerOn) return;
  buzzerOn = on;
  if (on) {
    tone(BUZZER_PIN, 4000);
  } else {
    noTone(BUZZER_PIN);
  }
}

const char *modeName(int selectedMode) {
  switch (selectedMode) {
    case 1: return "1 Viqri - kelembapan tanah";
    case 2: return "2 Ihwal - alarm kelembapan";
    case 3: return "3 Helmy - tinggi air berkedip";
    case 4: return "4 Prama - tinggi air 5 detik";
    case 5: return "5 Syamsidar - alarm RTC";
    case 6: return "6 Yuri - kekeruhan air";
    default: return "tidak dikenal";
  }
}

void announceMode() {
  Serial.print("Mode dipilih: ");
  Serial.println(modeName(mode));
}

void announceStartedMode() {
  Serial.print("Mode mulai berjalan: ");
  Serial.println(modeName(activeMode));
}

float readSoilPercent() {
  int raw = analogRead(SOIL_PIN);
  float percent = (float)(SOIL_DRY_RAW - raw) * 100.0f / (SOIL_DRY_RAW - SOIL_WET_RAW);
  percent = constrain(percent, 0.0f, 100.0f);
  Serial.print("Kelembapan tanah: ");
  Serial.print(percent, 1);
  Serial.println(" %");
  return percent;
}

float readWaterHeightCm() {
  digitalWrite(TRIG_PIN, LOW);
  delayMicroseconds(3);
  digitalWrite(TRIG_PIN, HIGH);
  delayMicroseconds(10);
  digitalWrite(TRIG_PIN, LOW);

  unsigned long durationUs = pulseIn(ECHO_PIN, HIGH, 30000UL);
  if (durationUs == 0) {
    Serial.println("HC-SR04 tidak mendapat pantulan.");
    return -1.0f;
  }
  float distanceCm = durationUs / 58.0f;
  float heightCm = constrain(TANK_REFERENCE_HEIGHT_CM - distanceCm, 0.0f, TANK_REFERENCE_HEIGHT_CM);
  Serial.print("Jarak sensor: ");
  Serial.print(distanceCm, 1);
  Serial.print(" cm, tinggi air: ");
  Serial.print(heightCm, 1);
  Serial.println(" cm");
  return heightCm;
}

float readTurbidityNtuEstimate() {
  // Pembagi 10k/20k menurunkan tegangan menjadi 2/3; kalikan 1,5 untuk tegangan sensor asli.
  uint32_t millivolts = analogReadMilliVolts(TURBIDITY_PIN);
  float sensorVoltage = (millivolts / 1000.0f) * 1.5f;
  // Perkiraan empiris yang umum dipakai untuk SEN0189. Kalibrasikan dengan sampel standar bila perlu.
  float ntu = -1120.4f * sensorVoltage * sensorVoltage + 5742.3f * sensorVoltage - 4352.9f;
  ntu = constrain(ntu, 0.0f, 5000.0f);
  Serial.print("Kekeruhan perkiraan: ");
  Serial.print(ntu, 0);
  Serial.println(" NTU");
  return ntu;
}

int waterBand(float heightCm) {
  if (heightCm < 0.0f || heightCm > 20.0f) return -1;
  if (heightCm <= 5.0f) return 0;
  if (heightCm <= 10.0f) return 1;
  return 2;
}

void showWaterBand(int band, bool on) {
  allLedsOff();
  if (!on) return;
  if (band == 0) digitalWrite(LED_RED_PIN, HIGH);
  if (band == 1) digitalWrite(LED_YELLOW_PIN, HIGH);
  if (band == 2) digitalWrite(LED_GREEN_PIN, HIGH);
}

void pollEncoder() {
  int currentClk = digitalRead(ENCODER_CLK_PIN);
  if (currentClk != lastEncoderClk && currentClk == LOW) {
    int direction = (digitalRead(ENCODER_DT_PIN) != currentClk) ? 1 : -1;
    if (activeMode == 5 && rtcSettingStage == 1) {
      rtcSetHour = (rtcSetHour + direction + 24) % 24;
    } else if (activeMode == 5 && rtcSettingStage == 2) {
      rtcSetMinute = (rtcSetMinute + direction + 60) % 60;
    } else {
      // Memutar encoder hanya memilih mode. Mode sebelumnya berhenti sampai pilihan baru diklik.
      mode += direction;
      if (mode > 6) mode = 1;
      if (mode < 1) mode = 6;
      activeMode = 0;
      rtcSettingStage = 0;
      mode4LastBand = -1;
      mode4LightUntilMs = 0;
      rtcAlarmUntilMs = 0;
      allLedsOff();
      setBuzzer(false);
      announceMode();
    }
  }
  lastEncoderClk = currentClk;

  int button = digitalRead(ENCODER_SW_PIN);
  if (button != lastButtonState && millis() - lastButtonChangeMs > 40) {
    lastButtonChangeMs = millis();
    lastButtonState = button;
    if (button == LOW) {
      // Klik pertama pada pilihan selalu menyalakan mode itu.
      if (activeMode != mode) {
        activeMode = mode;
        mode4LastBand = -1;
        mode4LightUntilMs = 0;
        rtcAlarmUntilMs = 0;
        setBuzzer(false);
        announceStartedMode();
      } else if (activeMode == 5 && rtcReady) {
        // Klik berikutnya di Mode 5 dipakai khusus untuk pengaturan jam RTC.
        rtcAlarmUntilMs = 0;
        setBuzzer(false);
        if (rtcSettingStage == 0) {
          DateTime current = rtc.now();
          rtcSetHour = current.hour();
          rtcSetMinute = current.minute();
          rtcSettingStage = 1;
          Serial.println("Atur jam RTC: putar encoder, lalu tekan untuk lanjut ke menit.");
        } else if (rtcSettingStage == 1) {
          rtcSettingStage = 2;
          Serial.println("Atur menit RTC: putar encoder, lalu tekan untuk menyimpan.");
        } else {
          DateTime current = rtc.now();
          rtc.adjust(DateTime(current.year(), current.month(), current.day(), rtcSetHour, rtcSetMinute, 0));
          rtcSettingStage = 0;
          Serial.println("Jam RTC sudah disimpan.");
        }
      } else {
        // Pada mode lain, klik saat sudah aktif hanya menghentikan bunyi alarm/buzzer yang sedang berjalan.
        rtcAlarmUntilMs = 0;
        setBuzzer(false);
      }
    }
  }
}

void writeLcdLine(uint8_t row, const char *text, char *previous) {
  char padded[17];
  snprintf(padded, sizeof(padded), "%-16.16s", text);
  if (strcmp(padded, previous) == 0) return;
  lcd.setCursor(0, row);
  lcd.print(padded);
  strcpy(previous, padded);
}

void updateLcd() {
  char line0[17];
  char line1[17];
  snprintf(line0, sizeof(line0), "Pilih M%d %.7s", mode, modeName(mode) + 2);
  if (activeMode == 0) {
    snprintf(line1, sizeof(line1), "Tekan: mulai");
  } else if (activeMode == 1 || activeMode == 2) snprintf(line1, sizeof(line1), "Tanah:%5.1f%%", soilPercent);
  else if (activeMode == 3 || activeMode == 4) snprintf(line1, sizeof(line1), "Air:%6.1f cm", waterHeightCm);
  else if (activeMode == 5 && rtcSettingStage == 1) {
    snprintf(line0, sizeof(line0), "Atur JAM: putar");
    snprintf(line1, sizeof(line1), "> %02d:%02d tekan", rtcSetHour, rtcSetMinute);
  } else if (activeMode == 5 && rtcSettingStage == 2) {
    snprintf(line0, sizeof(line0), "Atur MENIT:putar");
    snprintf(line1, sizeof(line1), "  %02d:>%02d tekan", rtcSetHour, rtcSetMinute);
  } else if (activeMode == 5) snprintf(line1, sizeof(line1), "Alarm %02d:%02d", RTC_ALARM_HOUR, RTC_ALARM_MINUTE);
  else snprintf(line1, sizeof(line1), "Keruh:%5.0f NTU", turbidityNtuEstimate);
  writeLcdLine(0, line0, lastLcdLine0);
  writeLcdLine(1, line1, lastLcdLine1);
}

void updateSensors(unsigned long nowMs) {
  if ((activeMode == 1 || activeMode == 2) && nowMs - lastSoilReadMs >= 500) {
    lastSoilReadMs = nowMs;
    soilPercent = readSoilPercent();
  }
  if ((activeMode == 3 || activeMode == 4) && nowMs - lastWaterReadMs >= 200) {
    lastWaterReadMs = nowMs;
    waterHeightCm = readWaterHeightCm();
  }
  if (activeMode == 6 && nowMs - lastTurbidityReadMs >= 500) {
    lastTurbidityReadMs = nowMs;
    turbidityNtuEstimate = readTurbidityNtuEstimate();
  }
}

void runMode(unsigned long nowMs) {
  allLedsOff();
  setBuzzer(false);

  if (activeMode == 1) {
    if (soilPercent < 35.0f) digitalWrite(LED_RED_PIN, HIGH);
    else digitalWrite(LED_GREEN_PIN, HIGH);
  } else if (activeMode == 2) {
    if (soilPercent < 40.0f && (nowMs % 500UL) < 250UL) setBuzzer(true);
  } else if (activeMode == 3) {
    int band = waterBand(waterHeightCm);
    showWaterBand(band, (nowMs % 500UL) < 250UL);
  } else if (activeMode == 4) {
    int band = waterBand(waterHeightCm);
    if (band != mode4LastBand) {
      mode4LastBand = band;
      mode4LightUntilMs = nowMs + 5000UL;
    }
    showWaterBand(band, band >= 0 && nowMs < mode4LightUntilMs);
  } else if (activeMode == 5 && rtcSettingStage == 0) {
    if (rtcReady && nowMs - lastRtcReadMs >= 500) {
      lastRtcReadMs = nowMs;
      DateTime current = rtc.now();
      uint32_t dateKey = (uint32_t)current.year() * 10000UL + (uint32_t)current.month() * 100UL + current.day();
      if (current.hour() == RTC_ALARM_HOUR && current.minute() == RTC_ALARM_MINUTE && dateKey != rtcAlarmDateKey) {
        rtcAlarmDateKey = dateKey;
        rtcAlarmUntilMs = nowMs + 10000UL;
        Serial.println("Alarm RTC aktif selama 10 detik.");
      }
    }
    if (nowMs < rtcAlarmUntilMs) setBuzzer(true);
  } else if (activeMode == 6) {
    if (turbidityNtuEstimate > 1000.0f) digitalWrite(LED_YELLOW_PIN, HIGH);
  }
}

void setup() {
  Serial.begin(115200);
  pinMode(LED_RED_PIN, OUTPUT);
  pinMode(LED_YELLOW_PIN, OUTPUT);
  pinMode(LED_GREEN_PIN, OUTPUT);
  pinMode(BUZZER_PIN, OUTPUT);
  pinMode(TRIG_PIN, OUTPUT);
  pinMode(ECHO_PIN, INPUT);
  pinMode(ENCODER_CLK_PIN, INPUT_PULLUP);
  pinMode(ENCODER_DT_PIN, INPUT_PULLUP);
  pinMode(ENCODER_SW_PIN, INPUT_PULLUP);
  analogReadResolution(12);
  allLedsOff();

  Wire.begin(I2C_SDA_PIN, I2C_SCL_PIN);
  lcd.init();
  lcd.backlight();
  writeLcdLine(0, "Sistem tani", lastLcdLine0);
  writeLcdLine(1, "Memulai...", lastLcdLine1);
  rtcReady = rtc.begin();
  if (rtcReady) {
    if (rtc.lostPower()) {
      rtc.adjust(DateTime(F(__DATE__), F(__TIME__)));
      Serial.println("RTC belum memiliki waktu; diatur ke waktu saat firmware dibuat.");
    }
  } else {
    Serial.println("DS3231 tidak ditemukan; Mode 5 tidak dapat berjalan sampai kabel RTC diperiksa.");
  }

  lastEncoderClk = digitalRead(ENCODER_CLK_PIN);
  lastButtonState = digitalRead(ENCODER_SW_PIN);
  announceMode();
}

void loop() {
  unsigned long nowMs = millis();
  pollEncoder();
  updateSensors(nowMs);
  runMode(nowMs);
  updateLcd();
  delay(5);
}