diff --git a/registre_airchaud_code.ino b/registre_airchaud_code.ino
index 5e573a0..0700b3e 100644
--- a/registre_airchaud_code.ino
+++ b/registre_airchaud_code.ino
@@ -52,8 +52,12 @@ AccelStepper myStepper(4, In1, In3, In2, In4);
 int prevDimValue=0;
 int newDimValue=0;
 char convBuffer[10];
+const int debattement = 2038 * 5;
 
-int pos=0;
+bool homed=false;
+// atmega328p pin 26 -> pc3 -> arduino A3;
+const int homing_pin = A3;
+int stopCourseBtnState = 0;
 
 unsigned long previousMillis = 0;
 const long tempInterval = 60000;
@@ -83,10 +87,13 @@ void setup() {
   myStepper.setSpeed(200);
   // myStepper.moveTo(2038);
   // todo make a homing of stepper motor OR find a way to sensorize where it is
-  myStepper.setCurrentPosition(0);
+  // myStepper.setCurrentPosition(0);
 
-  send(dimmerMsg.set(prevDimValue));
-  send(lightMsg.set(1));
+  pinMode(homing_pin, INPUT);
+  digitalWrite(homing_pin, HIGH);
+
+  // send(dimmerMsg.set(prevDimValue));
+  // send(lightMsg.set(1));
 
   sensors.begin();
 }
@@ -119,6 +126,32 @@ void loop() {
 	// if (myStepper.distanceToGo() == 0) 
 	// 	myStepper.moveTo(-myStepper.currentPosition());
 
+
+  // stopCourseBtnState = digitalRead(homing_pin);
+  // if (stopCourseBtnState == HIGH){
+  //   Serial.print('stopCourseBtnState HIGH');
+  // }
+
+  if (!homed)
+  {
+    myStepper.setSpeed(200);
+    if (myStepper.distanceToGo() == 0) {
+      myStepper.moveTo(myStepper.currentPosition() + 2038); // turn clockwise to go up 
+    }
+    stopCourseBtnState = digitalRead(homing_pin);
+    if (stopCourseBtnState == HIGH){
+      Serial.print("stopCourseBtnState is HIGH");
+      // stepper
+      myStepper.stop();
+      myStepper.setCurrentPosition(0);
+      // HA
+      send(dimmerMsg.set(prevDimValue));
+      send(lightMsg.set(1));
+
+      homed=true;
+    }
+  }
+  
 	// Move the motor one step
 	if(!myStepper.run()){
     // release the stepper motor to free power consumption
@@ -158,8 +191,14 @@ void receive(const MyMessage &message) {
       Serial.println(newDimValue);
     #endif
     
-    // todo instead of 1 revolution (2038) define how much revolution we want to do for full opening (100% of the dimmer in HA)
-    pos = (2038 / 100) * newDimValue;
-    myStepper.moveTo(pos); // move the stepper
+    if (homed)
+    {
+      // todo instead of 1 revolution (2038) define how much revolution we want to do for full opening (100% of the dimmer in HA)
+      myStepper.setSpeed(400);
+      int pos = (debattement / 100) * newDimValue * -1; // turn counter clock wise to go done
+      myStepper.moveTo(pos); // move the stepper
+
+    }
+    
   }
 }
\ No newline at end of file