ESP-32 ESP32 Wireless WiFi Bluetooth Development Board 2.4GHz CH9102 Micro USB Dual Core Module ESP-32U UK Seller Development board

// ESP32 4-Zone Irrigation Controller
// ADC: GPIO32,33,34,35
// Relays: GPIO25,26,27,14 (active HIGH)
// OLED I2C: SDA=21, SCL=22 (SSD1306 128x64)
// Tune thresholds[] (raw ADC 0..4095), wateringDurationMs[], minIntervalMs[]

#include <Wire.h>
#include <Adafruit_GFX.h>
#include <Adafruit_SSD1306.h>

#define SCREEN_WIDTH 128
#define SCREEN_HEIGHT 64
#define OLED_ADDR 0x3C

Adafruit_SSD1306 display(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, -1);

const int soilPins[4] = {32, 33, 34, 35};
const int relayPins[4] = {25, 26, 27, 14};

int thresholds[4] = {2000, 2000, 2000, 2000}; // adjust for your sensors
unsigned long wateringDurationMs[4] = {30UL*1000, 30UL*1000, 30UL*1000, 30UL*1000};
unsigned long minIntervalMs[4] = {60UL*60*1000, 60UL*60*1000, 60UL*60*1000, 60UL*60*1000};

int hysteresis = 150;

bool zoneActive[4] = {false,false,false,false};
unsigned long zoneStartTs[4] = {0,0,0,0};
unsigned long zoneLastWaterTs[4] = {0,0,0,0};

const unsigned long UI_UPDATE_MS = 2000;
unsigned long lastUiUpdate = 0;

void setup() {
  Serial.begin(115200);
  delay(100);
  for (int i=0;i<4;i++) {
    pinMode(relayPins[i], OUTPUT);
    digitalWrite(relayPins[i], LOW);
  }
  for (int i=0;i<4;i++) pinMode(soilPins[i], INPUT);

  Wire.begin(21,22);
  if (!display.begin(SSD1306_SWITCHCAPVCC, OLED_ADDR)) {
    Serial.println("OLED init failed - continuing without display");
  } else {
    display.clearDisplay();
    display.setTextColor(SSD1306_WHITE);
    display.setTextSize(1);
    display.setCursor(0,0);
    display.println("ESP32 4-Zone Irrigation");
    display.display();
    delay(800);
  }
}

int readSoilRaw(int zoneIndex) {
  return analogRead(soilPins[zoneIndex]); // 0..4095 (12-bit)
}

void startZone(int z) {
  zoneActive[z] = true;
  zoneStartTs[z] = millis();
  zoneLastWaterTs[z] = millis();
  digitalWrite(relayPins[z], HIGH);
  Serial.printf("Zone %d START\n", z+1);
}

void stopZone(int z) {
  zoneActive[z] = false;
  digitalWrite(relayPins[z], LOW);
  Serial.printf("Zone %d STOP\n", z+1);
}

void loop() {
  unsigned long now = millis();
  for (int z=0; z<4; z++) {
    int raw = readSoilRaw(z);
    bool needsWater = (raw > thresholds[z]);
    if (zoneActive[z]) {
      if (now - zoneStartTs[z] >= wateringDurationMs[z]) stopZone(z);
    } else {
      if (needsWater && (now - zoneLastWaterTs[z] >= minIntervalMs[z])) {
        if (raw > thresholds[z] + hysteresis) startZone(z);
      }
    }
  }

  if (now - lastUiUpdate >= UI_UPDATE_MS) {
    lastUiUpdate = now;
    if (display.getPtr() != nullptr) {
      display.clearDisplay();
      display.setTextSize(1);
      display.setCursor(0,0);
      display.println("4-Zone Irrigation");
      for (int z=0; z<4; z++) {
        int raw = readSoilRaw(z);
        display.printf("Z%d: %4d %s\n", z+1, raw, zoneActive[z]? "WATER":"OK  ");
      }
      display.display();
    }
    for (int z=0; z<4; z++) {
      int raw = readSoilRaw(z);
      Serial.printf("Zone %d: raw=%d state=%s\n", z+1, raw, zoneActive[z] ? "WATERING":"idle");
    }
  }

  delay(10);
}
  

esphome:
  name: esp32_irrigation_4zone
  platform: ESP32
  board: esp32dev

wifi:
  ssid: "YOUR_SSID"
  password: "YOUR_PASS"

logger:

i2c:
  sda: 21
  scl: 22
  scan: true

sensor:
  - platform: adc
    pin: GPIO32
    name: "Soil Zone 1"
    id: soil_z1
    update_interval: 10s
  - platform: adc
    pin: GPIO33
    name: "Soil Zone 2"
    id: soil_z2
    update_interval: 10s
  - platform: adc
    pin: GPIO34
    name: "Soil Zone 3"
    id: soil_z3
    update_interval: 10s
  - platform: adc
    pin: GPIO35
    name: "Soil Zone 4"
    id: soil_z4
    update_interval: 10s

switch:
  - platform: gpio
    pin: GPIO25
    id: valve1
    name: "Valve Zone 1"
  - platform: gpio
    pin: GPIO26
    id: valve2
    name: "Valve Zone 2"
  - platform: gpio
    pin: GPIO27
    id: valve3
    name: "Valve Zone 3"
  - platform: gpio
    pin: GPIO14
    id: valve4
    name: "Valve Zone 4"

automation:
  - alias: "Auto water zone 1"
    trigger:
      platform: numeric_state
      entity_id: sensor.soil_zone_1
      above: 0.7   # tune threshold (0..1)
    action:
      - switch.turn_on: valve1
      - delay: 30s
      - switch.turn_off: valve1

  - alias: "Auto water zone 2"
    trigger:
      platform: numeric_state
      entity_id: sensor.soil_zone_2
      above: 0.7
    action:
      - switch.turn_on: valve2
      - delay: 30s
      - switch.turn_off: valve2

  - alias: "Auto water zone 3"
    trigger:
      platform: numeric_state
      entity_id: sensor.soil_zone_3
      above: 0.7
    action:
      - switch.turn_on: valve3
      - delay: 30s
      - switch.turn_off: valve3

  - alias: "Auto water zone 4"
    trigger:
      platform: numeric_state
      entity_id: sensor.soil_zone_4
      above: 0.7
    action:
      - switch.turn_on: valve4
      - delay: 30s
      - switch.turn_off: valve4

display:
  - platform: ssd1306_i2c
    model: "SSD1306 128x64"
    address: 0x3C
    lambda: |-
      it.printf(0, 0, id(font1), "Z1: %.0f Z2: %.0f", id(soil_z1).state * 4095.0, id(soil_z2).state * 4095.0);
      it.printf(0, 16, id(font1), "Z3: %.0f Z4: %.0f", id(soil_z3).state * 4095.0, id(soil_z4).state * 4095.0);

font:
  - file: "fonts/arial.ttf"
    id: font1
    size: 12