Enhanced (sometimes "Expanded") IDE
is a standard electronic interface
between your computer and its mass
storage drives. EIDE's enhancements
to Integrated Drive Electronics
(IDE) make it possible to address a
hard disk larger than 528 Mbytes.
EIDE also provides faster access to
the hard drive, support for Direct
Memory Access (DMA), and support for
additional drives, including CD-ROM
and tape devices through the AT
Attachment Packet Interface.
When updating your computer with a
larger hard drive (or other drives),
an EIDE "controller" can be added to
your computer in one of its card
slot.
To access larger than 528 Mbyte
drives, EIDE (or the basic
input/output system that comes with
it) uses a 28-bit Logical Block
Address (LBA) to specify the actual
cylinder, head, and sector location
of data on the disk. The 28 bits of
the LBA provide enough information
to specify unique sectors for a
device up to 8.4 GB in size.
EIDE was adopted as a standard by
ANSI in 1994. ANSI calls it Advanced
Technology Attachment-2 (it's also
referred to as "Fast ATA").
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