Industry Standard Architecture

16-bit internal bus of the IBM PC/AT

Key facts

Year created: 1981 ; 45 years ago ( 1981 )
Created by: IBM
Superseded by: PCI , LPC (1993, 1998)
Width in bits: 8 or 16
Number span no of devices: up to 6 devices
Speed: Half-duplex 8 MB/s or 16 MB/s
Style: Parallel
Hotplugging interface: No
External interface: No

via Wikipedia infobox

Article

Industry Standard Architecture (ISA) is the 16-bit internal bus of IBM PC/AT and similar computers based on the Intel 80286 and its immediate successors during the 1980s. The bus was (largely) backward compatible with the 8-bit bus of the 8088-based IBM PC, including the IBM PC/XT as well as IBM PC compatibles.

Originally referred to as the PC bus (8-bit) or AT bus (16-bit), it was also termed I/O Channel by IBM. The ISA term was coined as a retronym by IBM PC clone manufacturers in the late 1980s or early 1990s as a reaction to IBM attempts to replace the AT bus with its new and incompatible Micro Channel architecture.