A hard disk drive, its use and production are described. A read/write disk stores digital data. A spindle motor supports the read/write disk for controlled rotation thereof. A head arrangement moves to selectively access the read/write disk in a data access mode and moves to a parked position. A dedicated input is receives a first sensor related input signal. A processing arrangement executes the data access mode by cooperatively controlling the spindle motor and the head arrangement, monitoring the sensor related input signal for a predetermined characteristic thereof, and responsive to detection of the characteristic, at least moves the head arrangement to the parked position. A hard disk drive multi-sensor group, monitoring technique and interface are described.