chore: v1

2026-03-29 22:19:17 +02:00
commit 5d2897e7e0
3 changed files with 294 additions and 0 deletions
--- a/.gitignore
+++ b/.gitignore
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+# macOS
+.DS_Store
+.AppleDouble
+.LSOverride
+*.swp
+*.swo
+*~
+.vscode/
+
+# Arduino
+build/
+.clang-format
+*.o
+*.a
+*.so
+*.so.*
+*.dylib
+*.dll
+*.exe
+
+# Arduino IDE
+.pioenvs/
+.piolibdeps/
+.pio/
+.vscode-pio
+
+# PlatformIO
+.platformio/
+platformio.ini
+
+# Build directories
+bin/
+obj/
+
+# Editor backups
+*.bak
+*.tmp
+
+# Dependencies and libraries
+node_modules/
+dist/
--- a/README.md
+++ b/README.md
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+# ESP32-C3 Fan Controller
+
+An automatic server fan controller built on the ESP32-C3, featuring temperature-based relay control, OLED status display, and Home Assistant integration via MQTT.
+
+## Features
+
+- **Auto fan control** — relay switches ON/OFF based on temperature thresholds with hysteresis
+- **DHT22 sensor** — reads temperature and humidity every second
+- **SSD1306 OLED** — displays live temp, humidity, and fan state
+- **MQTT publishing** — streams sensor data and fan state to Home Assistant
+- **WiFi** — connects on boot, auto-reconnects if MQTT drops
+
+## Hardware
+
+| Component | Details |
+|---|---|
+| Microcontroller | ESP32-C3 (with onboard OLED) |
+| Sensor | DHT22 (temperature + humidity) |
+| Relay | 5V relay module (active-LOW) |
+| Fan | USB 5V fan |
+| Display | SSD1306 128×64 OLED (I2C) |
+
+## Wiring
+
+| ESP32-C3 Pin | Connected To |
+|---|---|
+| `GPIO2` | DHT22 DATA (+ 4.7kΩ pullup to 3V3) |
+| `GPIO3` | Relay IN |
+| `GPIO5` (SDA) | OLED SDA |
+| `GPIO6` (SCL) | OLED SCL |
+| `3V3` | DHT22 VCC, OLED VCC |
+| `GND` | DHT22 GND, OLED GND, Relay GND |
+
+Relay wiring:
+- **COM** → USB 5V
+- **NO** → Fan + (red wire)
+- Fan − (black wire) → GND
+
+## Configuration
+
+Copy `secrets.h.example` to `secrets.h` and fill in your values:
+
+```cpp
+#define WIFI_SSID  "your_wifi_ssid"
+#define WIFI_PASS  "your_wifi_password"
+#define MQTT_HOST  "192.168.1.X"   // Home Assistant IP
+#define MQTT_USER  "mqtt_user"
+#define MQTT_PASS  "mqtt_pass"
+```
+
+### Temperature Thresholds
+
+Edit these defines in `fan_controller.ino`:
+
+```cpp
+#define TEMP_ON   28.0   // Fan turns ON above this (°C)
+#define TEMP_OFF  25.0   // Fan turns OFF below this (°C)
+```
+
+## MQTT Topics
+
+| Topic | Direction | Payload |
+|---|---|---|
+| `esp32c3/temperature` | Publish | `23.5` (°C) |
+| `esp32c3/humidity` | Publish | `41` (%) |
+| `esp32c3/fan/state` | Publish | `ON` / `OFF` |
+
+## Home Assistant Setup
+
+Add to `configuration.yaml`:
+
+```yaml
+mqtt:
+  sensor:
+    - name: "Room Temperature"
+      unique_id: "esp32c3_temperature"
+      state_topic: "esp32c3/temperature"
+      unit_of_measurement: "°C"
+      device_class: temperature
+
+    - name: "Room Humidity"
+      unique_id: "esp32c3_humidity"
+      state_topic: "esp32c3/humidity"
+      unit_of_measurement: "%"
+      device_class: humidity
+
+  binary_sensor:
+    - name: "Server Fan"
+      unique_id: "esp32c3_fan"
+      state_topic: "esp32c3/fan/state"
+      payload_on: "ON"
+      payload_off: "OFF"
+      device_class: running
+```
+
+Restart HA after saving. Requires the **Mosquitto broker** add-on installed and running.
+
+## Dependencies
+
+Install via Arduino IDE Library Manager:
+
+- [U8g2](https://github.com/olikraus/u8g2) — OLED display
+- [DHT sensor library](https://github.com/adafruit/DHT-sensor-library) — DHT22
+- [PubSubClient](https://github.com/knolleary/pubsubclient) — MQTT client
+- WiFi (built-in with ESP32 board package)
+
+## Project Structure
+
+```
+esp32c3-fan-controller/
+├── fan_controller.ino   # Main sketch
+├── secrets.h            # WiFi & MQTT credentials (gitignored)
+├── secrets.h.example    # Credentials template
+├── .gitignore
+└── README.md
+```
+
+## License
+
+MIT
--- a/arduino/main.ino
+++ b/arduino/main.ino
@@ -0,0 +1,133 @@
+#include <U8g2lib.h>
+#include <DHT.h>
+#include <WiFi.h>
+#include <PubSubClient.h>
+
+// --- WiFi ---
+#define WIFI_SSID "GL-AXT1800-714"
+#define WIFI_PASS "BDX924MWFW"
+
+// --- MQTT ---
+#define MQTT_HOST     "192.168.8.101"  // your HA IP
+#define MQTT_PORT     1883
+#define MQTT_USER     "mqtt_user"    // Mosquitto user
+#define MQTT_PASS     "Naughty0pArrot"
+#define MQTT_CLIENT   "esp32c3_fan"
+
+// Topics
+#define TOPIC_TEMP      "esp32c3_fan/temperature"
+#define TOPIC_HUMIDITY  "esp32c3_fan/humidity"
+#define TOPIC_FAN_STATE "esp32c3_fan/fan/state"
+#define TOPIC_FAN_CMD   "esp32c3_fan/fan/set"   // HA sends ON/OFF here
+
+// --- Pins ---
+#define DHTPIN    2
+#define DHTTYPE   DHT22
+#define RELAY_PIN 3
+
+// --- Thresholds ---
+#define TEMP_ON   28.0
+#define TEMP_OFF  25.0
+
+// --- OLED ---
+#define OLED_RESET U8X8_PIN_NONE
+#define OLED_SDA 5
+#define OLED_SCL 6
+
+U8G2_SSD1306_128X64_NONAME_F_HW_I2C u8g2(U8G2_R0, OLED_RESET, OLED_SCL, OLED_SDA);
+DHT dht(DHTPIN, DHTTYPE);
+WiFiClient wifiClient;
+PubSubClient mqtt(wifiClient);
+
+int xOffset = 30;
+int yOffset = 30;
+bool fanState = false;
+
+void setFan(bool on) {
+  fanState = on;
+  digitalWrite(RELAY_PIN, on ? LOW : HIGH);  // active-LOW relay
+  mqtt.publish(TOPIC_FAN_STATE, on ? "ON" : "OFF", true);
+}
+
+void connectWiFi() {
+  Serial.printf("Connecting to %s", WIFI_SSID);
+  WiFi.begin(WIFI_SSID, WIFI_PASS);
+  while (WiFi.status() != WL_CONNECTED) {
+    delay(500); Serial.print(".");
+  }
+  Serial.printf("\nWiFi connected: %s\n", WiFi.localIP().toString().c_str());
+}
+
+void connectMQTT() {
+  while (!mqtt.connected()) {
+    Serial.print("Connecting MQTT...");
+    if (mqtt.connect(MQTT_CLIENT, MQTT_USER, MQTT_PASS)) {
+      Serial.println("connected!");
+    } else {
+      Serial.printf("failed rc=%d, retry in 5s\n", mqtt.state());
+      delay(5000);
+    }
+  }
+}
+
+void handle_oled(float tempC, float humidity) {
+  char line1[20], line2[20], line3[20];
+  snprintf(line1, sizeof(line1), "T: %.1f C", tempC);
+  snprintf(line2, sizeof(line2), "H: %.0f %%", humidity);
+  snprintf(line3, sizeof(line3), "Fan: %s", fanState ? "ON" : "OFF");
+
+  u8g2.clearDisplay();
+  u8g2.clearBuffer();
+  u8g2.setFont(u8g2_font_4x6_tr);
+  u8g2.drawStr(xOffset, yOffset,      line1);
+  u8g2.drawStr(xOffset, yOffset + 10, line2);
+  u8g2.drawStr(xOffset, yOffset + 20, line3);
+  u8g2.sendBuffer();
+}
+
+void setup() {
+  Serial.begin(115200);
+  dht.begin();
+
+  pinMode(RELAY_PIN, OUTPUT);
+  setFan(false);  // fan OFF at boot
+
+  u8g2.begin();
+  u8g2.setContrast(255);
+  u8g2.setBusClock(400000);
+  u8g2.clearDisplay();
+
+  connectWiFi();
+  mqtt.setServer(MQTT_HOST, MQTT_PORT);
+  connectMQTT();
+
+  Serial.println("Ready.");
+}
+
+void loop() {
+  if (!mqtt.connected()) connectMQTT();
+  mqtt.loop();
+
+  float tempC    = dht.readTemperature();
+  float humidity = dht.readHumidity();
+
+  if (isnan(tempC) || isnan(humidity)) {
+    Serial.println("DHT22 read failed");
+    delay(2000);
+    return;
+  }
+
+  // Auto fan control with hysteresis
+  if (!fanState && tempC >= TEMP_ON)  setFan(true);
+  if (fanState  && tempC <= TEMP_OFF) setFan(false);
+
+  // Publish to MQTT
+  char buf[10];
+  dtostrf(tempC,    4, 1, buf); mqtt.publish(TOPIC_TEMP,     buf);
+  dtostrf(humidity, 4, 0, buf); mqtt.publish(TOPIC_HUMIDITY, buf);
+
+  Serial.printf("T:%.1fC  H:%.0f%%  Fan:%s\n", tempC, humidity, fanState ? "ON" : "OFF");
+  handle_oled(tempC, humidity);
+
+  delay(3000);
+}