Abstract: A boosted power-supply voltage is developed by the combination of three power drivers, a filter capacitor, and a Y-connected motor. Each of the power drivers includes a pair of transistors connected in a totem-pole configuration with a clamping (catch) diode connected between the collector and the emitter of the upper transistor. Rather than a power-supply voltage source, only the filter capacitor is connected to the collectors of the upper transistors, a reduced-voltage level DC power-supply voltage-source being connected to the motor-winding-common node.

Abstract: A process for determining the center of data disk tracks. The transducer head is positioned to one side of a track. The head repeatedly reads the track and microsteps across the track. The number of microsteps taken at the position on each side of the center of the track where a certain number of error correction code errors occur, are designated as boundaries of that track. The center of the track is then calculated as being half-way between the boundaries. By using the microstep off-sets for the centers of two tracks on a data disk, a correction factor can be calculated to compensate for thermal expansion of the data disk.

Abstract: An interconnection assembly permits a Winchester-type rigid magnetic disk storage unit, inclusive of the disk drive mechanism, to be plug-in removable from a systems unit or an add-on peripheral data storage subsystems unit of a personal computer system.

Abstract: A method of formatting a drive system for a magnetic data storage disk which eliminates the need for track-zero sensors. According to the method, formatting is begun at a first crash stop and proceeds across the disk to the opposite crash stop, in incremental steps from track to track.

Abstract: A system and method for controlling the operation of a dc stepping motor utilized for positioning a read/write head on a magnetic data storage disk operates to selectively establish different magnetic field strengths on the core members of the stepping motor, thereby minimizing the time period required to stop the motor at precise, preselected positions.

Abstract: Method and apparatus are provided for positioning a read/write head for transferring information between the head and a magnetic tape containing a plurality of information containing tracks. First and second opposed edges of a reference signal on the recording medium are located, and the locations of the first and second edges are used to calculate the position of the centerline of the reference signal. The centerline position is then utilized for accurate location of information - containing tracks on the recording medium. If no reference track is detected, reference signals are written on the medium, and the reference track location is stored in memory. The apparatus includes a drive means and a head means for reading/writing information, and the head means as indexing means to detect the edges of the reference signal.