Early Window

A data window that has been intentionally shifted in time in an early direction.

 

EBIOS

"Enhanced BIOS Services for Disk Drives". It is based on the T13 Technical Project Report, which describes new BIOS firmware services for supporting ATA hard disks up to 16 mega-tera-bytes (16x1018). This primarily refers to "Extended Interrupt 13" handled drives. Older BIOS services have a compatibility limitation of 528 MB and thus a theoretical maximum capacity of 8.4 GB.

 

Embedded Servo

A servo technique used for track following. Position information is prerecorded between data areas in a track so that a data head, and proper additional circuitry, can determine the data head location with respect to the center position of the track (or cylinder) in question.

 

Energy Star

EPA Energy Star Compliance: The U.S. Environmental Protection Agency's "Energy Star" program aims at reducing the electrical power consumption of computer equipment. Also known as "Green PC".

 

Enhanced Integrated Dsevice Electorincs (EIDE)

The popular name for the ATA-2 interface standard, which features a theoretical maximum data transfer rate of about 16MB/sec. In the real world, however, performance with devices on this interface typically maxes out at about 10MB/sec.

 

Enhanced Small Device Interface (ESDI)

An interface standard developed in the early 80s, by a consortium of the leading personal computer manufacturers for connecting disk drives to PCs. ESDI is two to three times faster than the older ST-506 standard. To use an ESDI drive, your computer must have an ESDI controller. ESDI is already obsolete. Instead, modern computers use a SCSI, IDE, EIDE, or Ultra DMA interface.

 

Erase

The process by which a signal recorded on a medium is removed and the medium is being made ready for rerecording.

 

Error Correction Code (ECC)

A mathematical algorithm that can detect and correct errors in a data field. This is accomplished with the aid of Check Bits added to the raw data.

 

Error Rate

The number of errors (of a specified type) that occur in a specified number of bits read.

 

Error Recovery Procedure

The process that occurs in response to a data error. In a drive without ECC, this would include re-calibration and re-seeking to the specified track and rereading the specified data.

 

Errot Free

A recording surface that has no defects.

 

Execute

To perform a data processing operation described by an instruction or a program.

 

Extra Pulse

The term used in surface certification. It is when a flux field discontinuity remains after the recording surface is erased, thereby producing an electrical output of a read head passing over the area with the discontinuity. An extra pulse occurs when the electrical output is larger than a specified threshold.