Methods and apparatus for detecting whether a removable cartridge disk drive is empty

摘要

The presence of a disk cartridge in a disk drive is detected by obtaining a measure of the load on the spindle motor of the disk drive and comparing that measure to a threshold value. The measure of load on the spindle motor may comprise (i) the time the spindle motor takes to spin-up to its full operating speed, (ii) the time the spindle motor takes to coast down to its operating speed from a first speed in excess of the operating speed, (iii) the voltage applied across the coils of the spindle motor, or (iv) the current drawn by the spindle motor.