*** Welcome to piglix ***

Parallel Advanced Technology Attachment

Parallel ATA
ATA on mainboard.jpgPATA-cable.jpg
Two ATA motherboard sockets on the left, with an ATA connector on the right.
Type Internal storage device connector
Designer Western Digital, subsequently amended by many others
Designed 1986
Superseded by Serial ATA (2003)
Hot pluggable No
External No
Cable 40 or 80 wires ribbon cable
Pins 40
Width 16 bits
Bitrate 16 MB/s originally
later 33, 66, 100 and 133 MB/s
Max. devices Two (master/slave)
Protocol Parallel
ATA Plug.svg
Pin 1 Reset
Pin 2 Ground
Pin 3 Data 7
Pin 4 Data 8
Pin 5 Data 6
Pin 6 Data 9
Pin 7 Data 5
Pin 8 Data 10
Pin 9 Data 4
Pin 10 Data 11
Pin 11 Data 3
Pin 12 Data 12
Pin 13 Data 2
Pin 14 Data 13
Pin 15 Data 1
Pin 16 Data 14
Pin 17 Data 0
Pin 18 Data 15
Pin 19 Ground
Pin 20 Key or VCC_in
Pin 21 DDRQ
Pin 22 Ground
Pin 23 I/O write
Pin 24 Ground
Pin 25 I/O read
Pin 26 Ground
Pin 27 IOCHRDY
Pin 28 Cable select
Pin 29 DDACK
Pin 30 Ground
Pin 31 IRQ
Pin 32 No connect
Pin 33 Addr 1
Pin 34 GPIO_DMA66_Detect
Pin 35 Addr 0
Pin 36 Addr 2
Pin 37 Chip select 1P
Pin 38 Chip select 3P
Pin 39 Activity
Pin 40 Ground

Parallel ATA (PATA), originally AT Attachment, is an interface standard for the connection of storage devices such as hard disk drives, floppy disk drives, and optical disc drives in computers. The standard is maintained by the X3/INCITS committee. It uses the underlying AT Attachment (ATA) and AT Attachment Packet Interface (ATAPI) standards.

The Parallel ATA standard is the result of a long history of incremental technical development, which began with the original AT Attachment interface, developed for use in early PC AT equipment. The ATA interface itself evolved in several stages from Western Digital's original Integrated Drive Electronics (IDE) interface. As a result, many near-synonyms for ATA/ATAPI and its previous incarnations are still in common informal use, in particular Extended IDE (EIDE) and Ultra ATA (UATA). After the introduction of Serial ATA (SATA) in 2003, the original ATA was renamed to Parallel ATA, or PATA for short.

Parallel ATA cables have a maximum allowable length of 18 in (457 mm). Because of this limit, the technology normally appears as an internal computer storage interface. For many years, ATA provided the most common and the least expensive interface for this application. It has largely been replaced by SATA in newer systems.

The PATA standard was originally conceived as the "AT Bus Attachment," abbreviated "ATA" because its primary feature was a direct connection to the 16-bit ISA bus introduced with the IBM PC/AT. The "AT" in "IBM PC/AT" refers to "Advanced Technology", but the ATA specifications published by the several standards committees simply use the name "AT Attachment" with no reference to advanced technology.


...
Wikipedia

...