Maxtor Corporation

Seagate Technology Incorporated

Robert L Metz

Jeffrey L Whaley

Lance R Carlson

Larry G Hutsell

Jeff Reh

Curt Bruner

Howard Barlow

John VanLaanen

Harold J Beecroft

Tim Everett

Gordon A Harwood

Daniel Nylander

Tracing of test information from a hardware device for debugging is formatted for transmission via a high-speed serial protocol. Data from various components in the hardware device is transmitted to an external test board using high speed serial ports. The number of serial ports needed for data transfer is significantly less than a complimentary parallel port configuration. Additional functional blocks on the chip process the data for high speed serial output. The functional blocks format information into subchannels, arbitrate data, append protocol, perform data integrity checks, and serialize the data. The additional blocks built on the chip to support the serial ports consume less chip space than the space consumed by the number of parallel ports required to provide equivalent data transfer rates. The process operates in near real time and may use time stamping to correlate and reconstruct data from different information sources. An input port receives data from the external test component to modify registers or memory, set break points, modify hardware status, communicate with processors, or modify other operating conditions to debug the hardware device.

High speed serial trace protocol for device debug

Various embodiments of the present invention are generally directed to processing servo data on a storage surface by detecting a time difference between consecutive read signal envelopes from spiral servo information on the surface.

Acquiring spiral servo information on a storage surface

The present invention relates to a system for determining whether the flying height of a read/write head above a disk in a disk drive is within an acceptable range, in substantially real time. The system relies on variations in read signal resolution with flying height to make the determination. In one embodiment, read signal resolution is measured and compared to a predetermined threshold value to determine whether the present flying height is in the desired range. In another embodiment, the number of peaks in a read signal that are detected (and/or not detected) by a detector is used to determine whether the head is in the proper flying height range. Because of read signal resolution effects, the number of detected peaks will decrease as the flying height of the head is increased. Means are also provided for postponing a transfer of data to/from the disk when it is determined that the head is not within the acceptable range.

Disk drive which detects head flying height using first and second non-overlapping data patterns with different frequencies

The present invention relates to a system for determining whether the flying height of a read/write head above a disk in a disk drive is within an acceptable range, in substantially real time. The system relies on variations in read signal resolution with flying height to make the determination. In one embodiment, read signal resolution is measured and compared to a predetermined threshold value to determine whether the present flying height is in the desired range. In another embodiment, the number of peaks in a read signal that are detected (and/or not detected) by a detector is used to determine whether the head is in the proper flying height range. Because of read signal resolution effects, the number of detected peaks will decrease as the flying height of the head is increased. The system also provides for postponing a transfer of data to/from the disk when it is determined that the head is not within the acceptable range.

Disk drive which detects head flying height using a peak count based on a data pattern

Disk drive which detects head flying height using a linearly increasing frequency data pattern

Disk drive which detects head flying height using a peak count based on a random data pattern

Disk drive which detects head flying height using first and second data patterns with different frequencies

An electronic architecture that provides a portable hard disk drive that can meet the type II PCMCIA specification and which can efficiently operate with a 3.3 V power supply. The architecture includes a digital signal processor with a first internal bus for transferring instructions and a second internal bus for transferring data. The digital signal processor performs fetching, decoding, reading and execution routines in parallel while simultaneously receiving data.

System architecture for hard disk drive

An electronic architecture that provides a portable hard disk drive that can meet the type II PCMCIA specification and which can efficiently operate with a 3.3 V power supply.

System architecture for HDD

Method and apparatus for detecting head flying height in a disk drive

Separate servo parameter values are combined into a single servo parameter value having a bit length shorter than the total bit length of the separate parameter values. The combined parameter value is then stored in a servo field on a storage disk. By storing the shorter combined parameter, a given amount of servo information can be stored in a smaller space on the disk, thereby reducing overhead. In one embodiment, servo parameters are added together to create the combined parameters. In another embodiment, an equation is provided for creating the combined parameters, that results in a relatively large numerical distance between combined parameters in adjacent servo sectors on a track of the storage disk. The combined parameters stored on the disk can be used, for example, to check the accuracy of software position estimators in the disk drive.

Technique for reducing overhead in a data storage system

Dual internal bus system architecture for hard disk drive

A hard disk drive that contains a detection circuit which senses the back emf of a voice coil. The detection circuit generates a shock detection signal when the back emf of the voice coil exceeds a pre-determined value. The write disable gate of the disk drive is disabled when the voltage detection circuit generates the shock detection signal.

Growing community of inventors

Westminster, CO, United States of America

Robert L Metz