commit 6864a37ed5c3a933bcb5f03dea098d7359df9c8d
Author: Ano-sys <timo.niemann02@gmail.com>
Date:   Tue Apr 1 14:47:35 2025 +0200

    Initial push

diff --git a/FanControlArduino.ino b/FanControlArduino.ino
new file mode 100644
index 0000000..a6406de
--- /dev/null
+++ b/FanControlArduino.ino
@@ -0,0 +1,57 @@
+#define PIN_RPM 9
+#define PIN_PWM 10
+
+volatile unsigned int pulseCount = 0;
+const unsigned int pulsesPerRevolution = 2;
+
+unsigned long previousMillis = 0;
+unsigned int rpm = 0;
+
+void rpmISR() {
+  pulseCount++;
+}
+
+int getSpeedForTemperature(){
+  static int i = 0;
+  switch(i++ % 5){
+    case 0: return 100;
+    case 1: return 140;
+    case 2: return 180;
+    case 3: return 220;
+    case 4: return 255;
+  }
+  return 255;
+}
+
+void setup() {
+  Serial.begin(115200);
+  
+  pinMode(PIN_RPM, INPUT_PULLUP);
+  pinMode(PIN_PWM, OUTPUT);
+
+  attachInterrupt(digitalPinToInterrupt(PIN_RPM), rpmISR, FALLING);
+  digitalWrite(PIN_PWM, HIGH);
+}
+
+void loop() {
+  uint8_t speed = getSpeedForTemperature();
+  unsigned long currentMillis = millis();
+  if(currentMillis - previousMillis >= 1000){
+    noInterrupts();
+    unsigned int count = pulseCount;
+    pulseCount = 0;
+    interrupts();
+
+    rpm = (count * 60) / pulsesPerRevolution;
+
+    Serial.println("Current Voltage: " + String(speed));
+    Serial.println("Current RPM: " + String(rpm));
+    Serial.println();
+
+    previousMillis = currentMillis;
+  }
+  
+  analogWrite(PIN_PWM, speed);
+  
+  delay(1000);
+}