This time I coded the homing sequence, which will help R2 center it’s head using the stepper motor. There will be an infrared sensor in the head, and at startup, R2 will turn its head slowly left, until the sensor detects it, and after this, the code will set the step count to 0. After this the head will automatically turn to look forward, while counting the steps. This is necessary to ensure that the head will move only in the safe limits, no matter in which position it was at startup. I took the help of Gemini at debugging.