Implement the anemometer sensor

firmware/config.h

@@ -1,13 +1,11 @@
 #define DEBUG
 
-#define WIFI_PASSWORD "xxx"
-#define WIFI_SSID "xxx"
-
 #define SENSOR_TEMPERATURE 0
 #define SENSOR_HUMIDITY    1
 #define SENSOR_LIGHT       2
+#define SENSOR_WINDSPEED   3
 
 #define UPDATE_INTERVAL 4
-#define STATUS_LED BUILTIN_LED
-
 
+#define STATUS_LED_PIN    BUILTIN_LED
+#define ANEMOMETER_PIN    D4

firmware/firmware.ino

@@ -21,7 +21,7 @@
  * - https://github.com/marvinroger/homie-esp8266
  */
 
-float currentSensorData[3] = {0.0, 0.0, 0.0};
+float currentSensorData[4] = {0.0, 0.0, 0.0, 0.0};
 
 void connectToWiFi() {
 }
@@ -29,17 +29,19 @@ bool checkWiFiConnection() {
   return true;
 }
 
-void setup() {
+void setup() { 
   #ifdef DEBUG
     Serial.begin(115200);
   #endif
   
-  pinMode(STATUS_LED, OUTPUT);
+  pinMode(STATUS_LED_PIN, OUTPUT);
+  pinMode(ANEMOMETER_PIN, INPUT_PULLUP);
+  
   connectToWiFi();
 }
 
 void loop() {
-  digitalWrite(STATUS_LED, LOW);
+  digitalWrite(STATUS_LED_PIN, LOW);
 
   while (!checkWiFiConnection()) {
     connectToWiFi();
@@ -49,13 +51,15 @@ void loop() {
   currentSensorData[SENSOR_TEMPERATURE] = fetchTemperature();
   currentSensorData[SENSOR_HUMIDITY] = fetchHumidity();
   currentSensorData[SENSOR_LIGHT] = fetchLight();
+  currentSensorData[SENSOR_WINDSPEED] = fetchWindspeed();
 
   #ifdef DEBUG
     Serial.println("");
     Serial.println("Current readings:");
-    Serial.println("Temperature: " + String(currentSensorData[SENSOR_TEMPERATURE]));
-    Serial.println("Humidity: " + String(currentSensorData[SENSOR_HUMIDITY]));
-    Serial.println("Light: " + String(currentSensorData[SENSOR_LIGHT]));
+    Serial.println("Temperature: " + String(currentSensorData[SENSOR_TEMPERATURE]) + " °C");
+    Serial.println("Humidity: " + String(currentSensorData[SENSOR_HUMIDITY]) + "%");
+    Serial.println("Light: " + String(currentSensorData[SENSOR_LIGHT]) + " Lumen");
+    Serial.println("Windspeed: " + String(currentSensorData[SENSOR_WINDSPEED]) + " Km/h");
   #endif
 
   pushToInfluxDB(currentSensorData);

firmware/sensors.ino

@@ -1,13 +1,31 @@
+int anemometerRotations = 0;
+unsigned long currentTime = 0;
 
 float fetchTemperature() {
-  return 22.5;
+  return 22.5; // XXX: Dummy value
 }
 
 float fetchHumidity() {
-  return 60.0;
+  return 60.0; // XXX: Dummy value
 }
 
 float fetchLight() {
-  return 2000.4;
+  return 2000.4; // XXX: Dummy value
+}
+
+void anemometerInterrupt() {
+  anemometerRotations++;
+}
+
+float fetchWindspeed() {
+  anemometerRotations = 0;
+  currentTime = millis();
+  int interruptNumber = digitalPinToInterrupt(ANEMOMETER_PIN);
+
+  attachInterrupt(interruptNumber, anemometerInterrupt, RISING);
+  delay(1000 * 5);
+  detachInterrupt(interruptNumber);
+
+  return (float)anemometerRotations / 5.0 * 2.4;
 }