Glossary

Actuator

Head positioning assembly. The actuator consists of a voice coil motor and head arm. If positions the read-write (R-W) head.

AT bus

A bus between the host CPU and adapter board

ATA (AT Attachment) standard

The ATA standard is for a PC AT interface regulated to establish compatibility between products manufactured by different vendors. Interfaces based on this standard are called ATA interfaces.

BIOS standard for drives

The BIOS standard collectively refers to the parameters defined by the host, which, for example, include the number of cylinders, the number of heads, and the number of sectors per track in the drive. The physical specifications of the drive do not always correspond to these parameters.

The BIOS of a PC AT cannot make full use of the physical specifications of these drivers. To make the best use of these drives, a BIOS that can handle the standard parameters of these drives is required.

Command

Commands are instructions to input data to and output data from a drive.

Commands are written in command registers.

Data block

A data block is the unit used to transfer data. A data block normally indicates a single sector.

DE

Disk enclosure. The DE includes the disks, built-in spindle motor, actuator, heads, and air filter. The DE is sealed to protect these components from dust.

MTBF

Mean time between failures. The MTBF is calculated by dividing the total operation time (total power-on time) by the number of failures in the disk drive during operation.

C141-E203-01EN

GL-1

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Fujitsu MHT2040BH, MHT2060BH, MHT2080BH manual Glossary