From d3922c85e7bdb6aefb45030ae5ac7b668717fcff Mon Sep 17 00:00:00 2001
From: Armel van Ravels <armel@armel.nl>
Date: Sun, 3 May 2026 20:45:53 +0200
Subject: [PATCH] Initial commit

---
 drybox.ino | 108 +++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 108 insertions(+)
 create mode 100644 drybox.ino

diff --git a/drybox.ino b/drybox.ino
new file mode 100644
index 0000000..95fc02b
--- /dev/null
+++ b/drybox.ino
@@ -0,0 +1,108 @@
+#include <AM2302-Sensor.h>
+#include <LiquidCrystal_I2C.h>
+
+LiquidCrystal_I2C lcd(0x27, 16, 2);
+
+constexpr unsigned int SENSOR_PIN {7U};
+AM2302::AM2302_Sensor am2302{SENSOR_PIN};
+
+const int potPin = A1;
+
+// Timing
+unsigned long lastLcdUpdate = 0;
+unsigned long lastSensorRead = 0;
+
+const unsigned long lcdInterval = 1000;
+const unsigned long sensorInterval = 2000;
+
+// State
+int lastMenuIndex = -1;
+float temperature = NAN;
+float humidity = NAN;
+
+const int relayPin = 12;
+
+unsigned long lastRelayToggle = 0;
+const unsigned long relayInterval = 2000;
+
+bool relayState = false;
+
+void readSensor(unsigned long now) {
+  if (now - lastSensorRead >= sensorInterval) {
+    lastSensorRead = now;
+
+    if (am2302.read() == AM2302::AM2302_READ_OK) {
+      humidity = am2302.get_Humidity();
+      temperature = am2302.get_Temperature();
+    }
+  }
+}
+
+void updateRelay(unsigned long now) {
+  if (now - lastRelayToggle >= relayInterval) {
+    lastRelayToggle = now;
+
+    relayState = !relayState; // toggle state
+    digitalWrite(relayPin, relayState ? HIGH : LOW);
+  }
+}
+
+void updateLCD(unsigned long now) {
+  int potValue = analogRead(potPin);
+
+  int menuIndex = (potValue < 512) ? 0 : 1;
+
+  if (menuIndex != lastMenuIndex || now - lastLcdUpdate >= lcdInterval) {
+    lastMenuIndex = menuIndex;
+    lastLcdUpdate = now;
+
+    lcd.clear();
+
+    if (menuIndex == 0) {
+      lcd.setCursor(0, 0);
+      lcd.print("Humidity:");
+
+      lcd.setCursor(0, 1);
+      if (!isnan(humidity)) {
+        lcd.print(humidity);
+        lcd.print("%");
+      } else {
+        lcd.print("No data");
+      }
+    }
+    else {
+      lcd.setCursor(0, 0);
+      lcd.print("Temperature:");
+
+      lcd.setCursor(0, 1);
+      if (!isnan(temperature)) {
+        lcd.print(temperature);
+        lcd.print(" C");
+      } else {
+        lcd.print("No data");
+      }
+    }
+  }
+}
+
+void setup() {
+
+  pinMode(relayPin, OUTPUT);
+  digitalWrite(relayPin, LOW); // start OFF
+
+  lcd.init();
+  lcd.backlight();
+
+  am2302.begin();
+
+  lcd.setCursor(0, 0);
+  lcd.print("Starting...");
+}
+
+void loop() {
+  unsigned long now = millis();
+
+  readSensor(now);
+  updateLCD(now);
+  updateRelay(now);
+}
\ No newline at end of file