Glossary

command or a group of linked commands. An I/O process normally ends with a BUS FREE phase following a COMMAND COMPLETE or a RELEASE RECOVERY message.

JUMPER – A tiny box,that slips over two pins on a circuit board, connecting the pins electrically. Some board manufacturers use Dual In-Line Package (DIP) switches instead of jumpers.

KILOBYTE (K) – A -unit of measure consisting of 1,024 (210) bytes.

LANDING ZONE .A non-data area on the disk’s inner cylinder where the heads can rest when the power is off

LATENCY – The time during which the read/ write heads wait for the data to rotate into position after the controller starts looking for a particular data track. If a disk rotates at 3,600 rpm, the maximum latency time is 16.4 milliseconds, and the average latency time is 8.2 milliseconds.

LBA – Abbreviation for Logical Block Address.

Asequentially-numbered identity of a multi- byte block of user data It does not refer directly to the physical location of the data in a disk drive.

LOGICAL FORMAT – The logical drive geometry that appears to the computer system BIOS as defined by the drive tables and stored in CMOS.

LOGICAL UNIT – A physical or virtual peripheral device addressable through a target.

LOOK AHEAD – The process of anticipating events in order to speed up computer operations. For example, the system can buffer data into cache RAM by reading blocks in advance, preparing the system for the next data request.

LOW-LEVEL FORMATTING – The process of creating sectors on the disk surface so that the operating system can access the required areas for generating the file structure. Maxtor drives are shipped with the low-level formatting already completed. Also known as initialization.

LOW PROFILE – Describes drives built to the

31/2-inch form factor, which are only 1 inch high. The standard form factor drives are 1.625 inches high.

LPS – Low Profile Series.

LOW-VOLTAGE DIFFERENTIAL (LVD)

Is a differential bus technology that combines much of the bus length, noise, immunity, and performance benefits to conventional differential SCSI with the power consumption and cost of single-ended SCSI Interfaces. Ultra2 SCSI (LVD) increase bus data rates to 80 Mbytes/sec, provides differential data integrity, extends the SCSI bus cable length to 12 meters, and provides easy system configuration for up to 15 peripherals.

MB – See megabyte. /

MAGNETO-RESISTIVE – A unique characteristic of some metals, which, when combined, yields a variable electrical resistance to varying magnetic fluxes. The resistance varies directly with the strength of the flux, field, not simply to a change in flux as with magneto- inductance.

MEDIA – The magnetic film that is deposited or coated on an aluminum substrate which is very flat and in the shape of a disk. The media is overcoated with a lubricant to prevent damage to the heads or media during head take off and landing. The media is where the data is stored inside the disk in the form of magnetic flux or polarity changes.

MEGABYTE (MB) – A unit of measurement equal to 1,000 kilobytes, or 1,024,000 bytes. (See also kilobyte.)

MEGAHERTZ – A measurement of frequency in millions of cycles per second.

MHz – See megahertz.

G-6Maxtor Atlas 10K III 18/36/73 GB Ultra160 SCSI

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Maxtor 10K III manual LOW-VOLTAGE Differential LVD