Backplanes have grown in complexity from the simple Industry Standard Architecture ( ISA ) ( used in the original IBM PC ) or S-100 style where all the connectors were connected to a common bus.

EISA extends the AT bus, which the Gang of Nine retroactively renamed to the ISA bus to avoid infringing IBM's trademark on its PC / AT computer, to 32 bits and allows more than one CPU to share the bus.

Unfortunately, because the ISA bus was originally locked to the processor clock, this meant that some 286 machines had ISA buses that ran at 10, 12, or even 16 MHz.

In fact, the first system to clock the ISA bus at 8 MHz was the turbo 8088 clones that clocked the processors at 8 MHz.

Other 386 PCs followed suit, and the AT ( later ISA ) bus remained a part of most systems even into the late 1990s.

Some of the 386 systems had proprietary 32-bit extensions to the ISA bus.

( The Industry Standard Architecture, or " ISA ", name replaced the " AT " name commonly used for the 16-bit bus.

Thus, even systems which didn't use the EISA bus gained the advantage of having the ISA standardized, which contributed to its longevity.

Industry Standard Architecture ( ISA ) is a computer bus standard for IBM PC compatible computers introduced with the IBM Personal Computer to support its Intel 8088 microprocessor's 8-bit external data bus and extended to 16 bits for the IBM Personal Computer / AT's Intel 80286 processor.

The ISA bus was developed by a team led by Mark Dean at IBM as part of the IBM PC project in 1981.

In 1988, the Gang of Nine IBM PC compatible manufacturers put forth the 32-bit EISA standard and in the process retroactively renamed the AT bus to " ISA " to avoid infringing IBM's trademark on its PC / AT computer.

Therefore, the ISA bus was synchronous with the CPU clock, until sophisticated buffering methods were developed and implemented by chipsets to interface ISA to much faster CPUs.

Designed to connect peripheral cards to the motherboard, ISA allows for bus mastering although only the first 16 MB of main memory are available for direct access.

This board has few onboard peripherals, as evidenced by the 6 slots provided for ISA bus | ISA cards and the lack of other built-in external interface connectors

The PCI Local Bus was first implemented in IBM PC compatibles, where it displaced the combination of ISA plus one VESA Local Bus as the bus configuration.

VESA ( Video Electronics Standards Association ) Local Bus worked alongside the ISA bus ; it acted as a high-speed conduit for memory-mapped I / O and DMA, while the ISA bus handled interrupts and port-mapped I / O.

Ironically, one of the benefits to come out of the EISA standard was a final codification of the standard to which ISA slots and cards should be held ( in particular, clock speed was fixed at an industry standard of 8. 33 MHz ).

The ISA then was renamed New York Branch-International Scientific Association ( NYB-ISA ).

The International Seabed Authority ( ISA ) (, ) is an intergovernmental body based in Kingston, Jamaica, that was established to organize and control all mineral-related activities in the international seabed area beyond the limits of national jurisdiction, an area underlying most of the world ’ s oceans.

The ISA was extended in 1996 to 64-bits, with this revision named PA-RISC 2. 0.

In the early 1990s the I / O bandwidth of the ISA bus was becoming a critical bottleneck to PC graphics performance.

While IBM's attempt at producing a successor to ISA with the Micro Channel Architecture was a technically viable option, it failed in the market due to its proprietary nature and imposed licensing fees.

The competing EISA open standard was still unable to offer enough performance improvement over ISA to provide a solution.

A " VLB slot " itself was simply an additional edge connector placed in-line with the traditional ISA or EISA connector, with this extended portion often colored a distinctive brown.

The result was a normal ISA or EISA slot being additionally capable of accepting VLB compatible cards.

The VESA Local Bus was designed as a stopgap solution to the problem of the ISA bus's limited bandwidth.

On 27 June 2001, the Intelligence Services Act 2001 ( ISA ) was introduced into Parliament by then Minister for Foreign Affairs Alexander Downer, which proposed significant changes to the Australian Intelligence Community ( AIC ).

On 15 October 2003, the Intelligence Services Amendment Bill 2003 was introduced into Parliament by Foreign Minister Alexander Downer, as an amendment to the original Intelligence Services Act 2001 ( ISA ).

The DMA controller chip was included on the PLUS-type memory expansion board for the EX and HX, and on regular ISA memory expansion cards sold by Tandy and other companies for the 1000, 1000A, and 1000HD.

However, it was not a full AT-class machine, as it still had an 8-bit ISA bus and only 8 IRQs.

was eventually standardized as ANSI / ISA S50, “ Compatibility of Analog

The first implementation of the 88000 ISA was the MC88100 microprocessor, which included an integrated FPU.

Even further, " AT-class " became a term describing any machine which supported the BIOS functions, 16-bit expansion slots, keyboard interface, and other defining technical features of the IBM PC AT ; in the case of the expansion slots, the term is largely synonymous with " ISA " ( when the latter is not applied as a retronym to XT-class machines, as in the phrase " 8-bit ISA slot ".

The introduction of the AGP format further complicated matters, as the design not only increased the pincount on riser cards, but it limited most cards to one AGP, one PCI and one ISA slot, which was too restrictive for most users.

EISA, the 32-bit extended version of ISA championed by Compaq, was used on some PC motherboards until 1997, when Microsoft declared it a " legacy " subsystem in the PC 97 industry white-paper.

The popularity of IBM's first personal computers made the ISA bus, first used on the IBM PC in 1981 and later extended to 16-bit in 1984 with the IBM PC / AT, the undisputed standard expansion bus for personal computers shortly after.

PICMG 1. 0, 1. 1 and 1. 2 provide for ISA and PCI support with 1. 2 adding PCIX support.

PC Floppy controllers ( ISA or onboard, but not USB floppy drives ) are able to deal with the 1581 format without need for any special tricks.

ELSA Winner 1000 for ISA and EISA.

Unlike MCA, EISA can accept older XT and ISA boards — the lines and slots for EISA are a superset of ISA.

* ISA platform (" NOS "), an operating system software for Nokia mobile telephones

* Use of collected money for wealth redistribution in addition to ISA administration

ISA cards, due to often cheap design and construction, are notorious for this problem.

As of 2007, two 64-bit RISC architectures are still produced in volume for non-embedded applications: SPARC and Power ISA.

MIPS ( originally an acronym for Microprocessor without Interlocked Pipeline Stages ) is a reduced instruction set computer ( RISC ) instruction set architecture ( ISA ) developed by MIPS Technologies ( formerly MIPS Computer Systems, Inc .).

PCI video cards replaced ISA and VESA cards, until growing bandwidth requirements outgrew the capabilities of PCI ; the preferred interface for video cards became AGP, and then PCI Express.

In 1994 DEC sold the PDP-11 system-software rights to Mentec Inc., an Irish producer of LSI-11 based boards for Q-Bus and ISA architecture personal computers, and in 1997 discontinued PDP-11 production.

Thus for a short time, hardware producers created proprietary implementations of local busses on their motherboards to give graphics cards direct access to the processor and system memory-and avoid the limitations of the ISA bus.

Tru64 UNIX is a 64-bit UNIX operating system for the Alpha instruction set architecture ( ISA ), currently owned by Hewlett-Packard ( HP ).