Abstract: An MTP-capable USB device and methods for use therewith are disclosed. The USB device is provided with circuitry operative to communicate with a host device using a media transfer protocol and receive a command from the host device to play content stored in the memory of the USB device. In one embodiment, the USB device is free of a user input device for providing a command to the circuitry to play content stored in the memory. In another embodiment, the USB device is free of a display device. In yet another embodiment, the USB device comprises a housing comprising a USB Flash drive form factor. Other embodiments are provided, and each of these embodiments can be used alone or in combination with one another.

Abstract: A low profile disk drive assembly comprises an enclosure having a sealed volume substantially laterally displaced with respect to a circuit volume. The sealed volume has an extension which extends laterally toward one corner portion of the enclosure whereas the circuit volume is disposed substantially within an adjacent corner portion of the enclosure. The sealed volume contains one or more disks and a read/write head actuator assembly. A flexible circuit, which couples to the read/write head actuator assembly inside the sealed volume, extends from inside sealed volume, through a wall of the enclosure which separates the sealed volume from the circuit volume, across the circuit volume, and to an interface connector. The interface connector may be used to connect the disk drive assembly to a system with which the disk drive assembly is to operate. A multichip module is mounted on one side of the flexible circuit inside the circuit volume.

Abstract: A method is provided for allocating digital processing activities of an embedded microcontroller within a disk drive between repetitive periodic digital servo loop service routines synchronized to rotation of a data storage disk of the drive and irregularly occurring host service routines supporting a high level, digital interface to a host computing environment. The new method comprises the steps of:prioritizing the host service routines into priority routines and non-priority routines,detecting calls to one of the priority routines, andbypassing execution of a predetermined number of the servo loop service routines to enable execution of the called priority routine without interruption.

Abstract: A disk drive includes at least one reference track having a plurality of sectors which are read and averaged in order to compensate for spindle offset. The disk drive has a head position servo system controls a head position actuator and includes a polyphase optical encoder which is initially calibrated by reference to dark current values and recalibrated periodically by reference to the reference track. Preferably, at least two reference tracks are located at the extremes of the radial displacement of the actuator so that variations in gap dimension between a scale mounted to the actuator and a fixed reticle-mask over a photodetector array of the encoder may be measured and compensated for. The method for initializing the drive and for periodically updating its calibration of the encoder and the head position servo is also described.

Abstract: A micro-Winchester disk drive subsystem includes a data block sequencer, cache memory and interface for a host computing machine. The drive includes a base and a plurality of non-removable directly rotated disks forming data storage surfaces. A balanced rotary head transducer actuator is mounted to the base for a plurality of data transducer heads among a multiplicity of concentric data tracks formed on each data storage surface of each of the disks. The track following servo system includes a position encoder coupled between the actuator structure and the base, prerecorded data track centerline information at a radially outermost region and at a radially innermost region of each data surface, and a temperature sensor for sensing temperature of the base at the vicinity of the position encoder.

Abstract: A micro-Winchester disk drive subsystem includes a data block sequencer, cache memory and interface for a host computing machine. The drive includes a base and a plurality of non-removable directly rotated disks forming data storage surfaces. A balanced rotary head transducer actuator is mounted to the base for a plurality of data transducer heads among a multiplicity of concentric data tracks formed on each data storage surface of each of the disks. The track following servo system includes a position encoder coupled between the actuator structure and the base, prerecorded data track centerline information at a radially outermost region and at a radially innermost region of each data surface, and a temperature sensor for sensing temperature of the base at the vicinity of the position encoder.

Abstract: An analog servo system suitable for accurately controlling the carriage speed of a high speed printer over a relatively wide range. The system includes an analog tachometer with circuit means which enables the tachometer to operate in either a high gain mode (used at normal or lower carriage speeds) or a low gain mode (used at higher carriage speeds). The tachometer gain mode (or "electronic gear") is controlled by an external command signal such as a single bit supplied by the control microprocessor of the printer. The state of the command signal controls a time constant in the tachometer circuit means which determines the gain mode.

Abstract: A nominal carriage velocity profile is initiated during each carriage positioning interval which enables the carriage to be decelerated and stopped at the proper position for printing. However, the carriage velocity profile can be modified during the positioning interval to avoid decelerating if printing can occur on the fly; i.e., if the print element (and ribbon) are able to complete any necessary positioning by the time the carriage arrives at its printing position. In accordance with the preferred embodiment, the slave microprocessor produces a READY signal in advance of the print wheel arriving at its destination orientation. The READY signal indicates that both the print wheel and ribbon will reach their destinations and be ready for printing within a fixed time interval; e.g., three milliseconds. In response to the READY signal, the master microprocessor inhibits further adjustments in the carriage speed and permits the carriage to assume a "fly" mode.