Three EISA Slots.

The Extended Industry Standard Architecture (in practice almost always shortened to EISA and frequently pronounced "eee-suh") is a bus standard for IBM compatible computers. It was announced in late 1988 by PC clone vendors (the "Gang of Nine") as a counter to IBM's use of its proprietary MicroChannel Architecture (MCA) in its PS/2 series. Year 1988 (MCMLXXXVIII) was a leap year starting on Friday (link displays 1988 Gregorian calendar). ... The Gang of Nine was a group of IBM competitors who came together in 1988 to build the EISA architecture, to compete with IBMs MCA. These companies were AST Research, Compaq Computer, Epson, Hewlett-Packard, NEC, Olivetti, Tandy, WYSE, and Zenith Data Systems. ... 64-bit PCI expansion slots inside a Power Macintosh G4 The Peripheral Component Interconnect, or PCI Standard (in practice almost always shortened to PCI) specifies a computer bus for attaching peripheral devices to a computer motherboard. ... This article is about the unit of information. ... In computing, a parallel port is an interface from a computer system where data is transferred in or out in parallel, that is, on more than one wire. ... Image File history File linksMetadata Download high resolution version (558x655, 131 KB) File links The following pages link to this file: Extended Industry Standard Architecture Metadata This file contains additional information, probably added from the digital camera or scanner used to create or digitize it. ... Image File history File linksMetadata Download high resolution version (558x655, 131 KB) File links The following pages link to this file: Extended Industry Standard Architecture Metadata This file contains additional information, probably added from the digital camera or scanner used to create or digitize it. ... One of the first PCs from IBM - the IBM PC model 5150. ... The NASA Columbia Supercomputer. ... Year 1988 (MCMLXXXVIII) was a leap year starting on Friday (link displays 1988 Gregorian calendar). ... This article or section does not cite its references or sources. ... The Gang of Nine was a group of IBM competitors who came together in 1988 to build the EISA architecture, to compete with IBMs MCA. These companies were AST Research, Compaq Computer, Epson, Hewlett-Packard, NEC, Olivetti, Tandy, WYSE, and Zenith Data Systems. ... Proprietary software is software with restrictions on using, copying and modifying as enforced by the proprietor. ... Micro Channel architecture (in practice almost always shortened to MCA) was a proprietary 16 or 32-bit parallel computer bus created by IBM in the 1980s for use on their new PS/2 computers. ... PS/2 can refer to: IBM Personal System/2, a series of post-PC computers sold by IBM starting in 1987. ...

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. The bus mastering support is also enhanced to provide access to 4 GB of memory. Unlike MCA, EISA can accept older XT and ISA boards — the lines and slots for EISA are a superset of ISA. A retronym is a type of neologism coined for an old object or concept whose original name has come to be used for something else, is no longer unique, or is otherwise inappropriate or misleading. ... This article or section does not adequately cite its references or sources. ... The IBM Personal Computer/AT (IBM 5170), more commonly known as the IBM AT and also sometimes called the PC AT or PC/AT, was IBMs second-generation PC, designed around the Intel 80286 microprocessor running at 6 MHz and released in 1984. ... This article is about the unit of information. ... Die of an Intel 80486DX2 microprocessor (actual size: 12×6. ... This article does not cite any references or sources. ... A gigabyte (derived from the SI prefix giga-) is a unit of information or computer storage equal to one billion (short scale) bytes or 230 bytes (1024 mebibytes)[1]. It is commonly abbreviated GB (not to be confused with Gb, which is used for gigabits). ... Industry Standard Architecture (in practice almost always shortened to ISA) is a computer bus standard for IBM compatibles. ...

Although somewhat inferior to MCA, EISA was much favoured by manufacturers due to the proprietary nature of MCA, and even IBM produced some machines supporting it. It was somewhat expensive to implement (though not as much as MCA), so it never became particularly popular in desktop PCs. However, it was reasonably successful in the server market, as it was better suited to bandwidth-intensive tasks (such as disk access and networking). Most EISA cards produced were either SCSI or network cards. EISA was also available on some non-IBM compatible machines such as the AlphaServer, HP 9000-D, SGI Indigo2 and MIPS Magnum. This article or section does not cite any references or sources. ... DEC Alpha AXP 21064 Microprocessor die photo Package for DEC Alpha AXP 21064 Microprocessor Alpha AXP 21064 bare die mounted on a business card with some statistics The DEC Alpha, also known as the Alpha AXP, is a 64-bit RISC microprocessor originally developed and fabricated by Digital Equipment Corp... HP 9000 is the name for a line of computer systems produced by the Hewlett-Packard (HP) company. ... An SGI Indigo2 IMPACT R10000 The SGI Indigo2 and the SGI Challenge M were UNIX machines marketed by SGI from 1993 to 1997. ... A MIPS Magnum 3000 (RC3230) The MIPS Magnum was a line of computer workstations designed by MIPS Computer Systems, Inc. ...

By the time there was a strong market need for a bus of these speeds and capabilities, the VESA Local Bus and later PCI filled this niche and EISA vanished into obscurity. This article or section does not cite any references or sources. ... 64-bit PCI expansion slots inside a Power Macintosh G4 The Peripheral Component Interconnect, or PCI Standard (in practice almost always shortened to PCI) specifies a computer bus for attaching peripheral devices to a computer motherboard. ...

History

The original IBM PC included five 8-bit slots, running at the system clock speed of 4.77MHz. The PC/AT, introduced in 1984, had three 8-bit slots and five 16-bit slots, all running at the system clock speed of 8MHz in the last version of the computer. The 16-bit slots were a superset of the 8-bit configuration, so most 8-bit cards were able to plug into a 16-bit slot (some cards used a "skirt" design that interfered with the extended portion of the slot) and continue to run in 8-bit mode. One of the key reasons for the success of the IBM PC (and the PC clones that followed it) was the active ecosystem of third-party expansion cards available for the machines. IBM made no attempt to patent the bus, and widely published the bus specifications. IBM PC (IBM 5150) with keyboard and green screen monochrome monitor (IBM 5151), running MS-DOS 5. ... The IBM Personal Computer/AT (IBM 5170), more commonly known as the IBM AT and also sometimes called the PC AT or PC/AT, was IBMs second-generation PC, designed around the Intel 80286 microprocessor running at 6 MHz and released in 1984. ...

As the PC-clone industry continued to build momentum in the mid- to late-1980's, several problems with the bus began to be apparent. First, because the "AT slot" (as it was known at the time) was not managed by any central standards group, there was nothing to prevent a manufacturer from "pushing" the standard. One of the most common issues was that as 286-based clones became more common, PC manufacturers began ratcheting up the processor speed to maintain a competitive advantage. Unfortunately, because the AT slot was originally locked to the processor clock, this meant that some 286 machines had slots that ran at 10, 12, or even 16MHz. This caused many issues with incompatibility, where a true IBM-compatible third-party card (designed for an 8MHz bus) might not work in a higher speed system (or even worse, would work unreliably). Most PC makers eventually decoupled the slot clock from the system clock, but there was still no standards body to "police" the industry. AMD 80286 at 12 MHz. ...

The AT bus architecture was so well entrenched that no single clone manufacturer had the leverage to create an alternative, and there was no compelling reason for them to cooperate on a new standard. Because of this, when the first 386-based system (the Compaq Deskpro 386) hit the market in 1986, it still sported 16-bit slots. Other 386 PCs followed suit, and the AT (later ISA) bus remained a part of most systems even into the late 1990's. The Intel 80386 is a microprocessor which was used as the central processing unit (CPU) of many personal computers from 1986 until 1994 and later. ... Compaq Computer Corporation is an American personal computer company founded in 1982, and now a brand name of Hewlett-Packard. ... The Compaq Deskpro was a line of personal computers manufactured by Compaq. ...

Meanwhile, IBM began to worry that it was losing control of the industry it had created. In 1987, IBM released the PS/2 line of computers, which included the MCA bus. MCA included numerous enhancements over the 16-bit AT bus, including bus mastering, burst mode, software configurable resources, and 32-bit capabilities. However, in an effort to reassert its dominant role, IBM patented the bus, and placed stringent licensing and royalty policies on its use. A few manufacturers did produce licensed MCA machines (most notably NCR), but overall the industry balked at IBM's restrictions. The Personal System/2 or PS/2 was IBMs second generation of personal computers. ... This article or section does not adequately cite its references or sources. ... This article does not cite any references or sources. ... Burst mode (alternatively burst-mode, with an hyphen) is a generic computing term referring to any situation in which a device is transmitting data repeatedly without waiting for input from another device or waiting for an internal process to terminate before continuing the transfer of data. ... NCR Corporation (NYSE: NCR) is a technology company specializing in solutions for the retail and financial industries. ...

In response, a group of PC manufacturers (the "Gang of Nine"), led by Compaq, created a new bus, which was named the Extended Industry Standard Architecture, or "EISA" (the Industry Standard Architecture, or "ISA", name replaced the "AT" name commonly used for the 16-bit bus). This provided virtually all of the technical advantages of MCA, while remaining compatible with existing 8-bit and 16-bit cards, and (most enticing to system and card makers) minimal licensing cost. The Gang of Nine was a group of IBM competitors who came together in 1988 to build the EISA architecture, to compete with IBMs MCA. These companies were AST Research, Compaq Computer, Epson, Hewlett-Packard, NEC, Olivetti, Tandy, WYSE, and Zenith Data Systems. ... This article or section does not adequately cite its references or sources. ...

The first EISA computers to hit the market were the Compaq Deskpro 486 and the SystemPro. The SystemPro, being one of the first PC-style systems designed as a network server, was built from the ground up to take full advantage of the EISA bus. It included such features as multiprocessing, hardware RAID, and bus-mastering network cards. The Systempro from Compaq was arguably the first true PC based server. ... This article or section does not cite any references or sources. ... Multiprocessing is traditionally known as the use of multiple concurrent processes in a system as opposed to a single process at any one instant. ... In computing, specifically computer storage, a Redundant Array of Independent Drives (or Disks), also known as Redundant Array of Inexpensive Drives (or Disks), (RAID) is an umbrella term for data storage schemes that divide and/or replicate data among multiple hard drives. ...

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 8.33MHz). Thus, even systems which didn't use the EISA bus gained the advantage of having the ISA standardized, which contributed to its longevity. Look up isa in Wiktionary, the free dictionary. ...

Technical data

Although the EISA bus had a slight performance disadvantage over MCA (bus speed of 8.33MHz, compared to 10MHz), EISA contained almost all of the technological benefits that MCA boasted, including bus mastering, burst mode, software configurable resources, and 32-bit data/address buses. These brought EISA nearly to par with MCA from a performance standpoint, and EISA easily defeated MCA in industry support. Image File history File links Download high resolution version (945x1536, 68 KB) File links The following pages link to this file: Extended Industry Standard Architecture ... Look up pin in Wiktionary, the free dictionary. ... This article does not cite any references or sources. ... Burst mode (alternatively burst-mode, with an hyphen) is a generic computing term referring to any situation in which a device is transmitting data repeatedly without waiting for input from another device or waiting for an internal process to terminate before continuing the transfer of data. ...

EISA replaced the tedious jumper configuration common with ISA cards with software-based configuration. Every EISA system shipped with an EISA configuration utility; this was usually a slightly customized version of the standard utilities written by the EISA chipset makers. The user would boot into this utility, either from floppy disk or on a dedicated hard drive partition. The utility software would detect all EISA cards in the system, and could configure any hardware resources (interrupts, memory ports, etc) on any EISA card (each EISA card would include a disk with information that described the available options on the card), or on the EISA system motherboard. The user could also enter information about ISA cards in the system, allowing the utility to automatically reconfigure EISA cards to avoid resource conflicts. Top: jumper block on IDE hard drive with shunt; bottom: assorted shunts In electronics and particularly computing, a jumper is two or more connecting points that can be conveniently shorted together to set up or adjust a printed circuit board, such as a computers motherboard. ... A floppy disk is a data storage device that is composed of a disk of thin, flexible (floppy) magnetic storage medium encased in a square or rectangular plastic shell. ... In computing, an interrupt request (or IRQ) is a phrase used to refer to either the act of interrupting the bus lines used to signal an interrupt, or the interrupt input lines on a Programmable Interrupt Controller (PIC). ... A motherboard is the central or primary circuit board making up a complex electronic system, such as a modern computer. ...

Similarly, Windows 95, with its Plug-and-Play capability, was not able to change the configuration of EISA cards, but it could detect the cards, read their configuration, and reconfigure Plug and Play hardware to avoid resource conflicts. Windows 95 would also automatically attempt to install appropriate drivers for detected EISA cards. Windows 95 is a consumer-oriented graphical user interface-based operating system. ... Plug and Play is a term used in the computer field to describe a computers ability to have new devices, normally peripherals, added to it without having to restart the computer. ...

Trivia

• When it became clear to IBM that Micro Channel was dying, IBM licensed EISA for use in a few server systems. As a final jab at their competitor, Compaq (leader of the EISA consortium) didn't cash the first check sent by IBM for the EISA license. Instead, the check was put on display in the company museum at Compaq's main campus in Houston, Texas.

• EISA's success was far from guaranteed. Many manufacturers, including those in the "Gang of Nine", researched the possibility of using MCA. For example, Compaq actually produced prototype DeskPro systems using the bus. However, these were never put into production, and when it was clear that MCA had lost, Compaq allowed its MCA license to expire (the license actually cost relatively little; the primary costs associated with MCA, and at which the industry revolted, were royalties to be paid per system shipped).

See also

• Industry Standard Architecture (ISA)
• Micro Channel architecture (MCA)
• NuBus
• VESA Local Bus (VESA)
• Peripheral Component Interconnect (PCI)
• Accelerated Graphics Port (AGP)
• PCI Express (PCIe)
• List of device bandwidths

This article or section does not adequately cite its references or sources. ... This article or section does not adequately cite its references or sources. ... NuBus is a 32-bit parallel computer bus, originally developed at MIT as a part of the NuMachine workstation project, and eventually used by Apple Computer and NeXT Computer. ... This article or section does not cite any references or sources. ... 64-bit PCI expansion slots inside a Power Macintosh G4 The Peripheral Component Interconnect, or PCI Standard (in practice almost always shortened to PCI) specifies a computer bus for attaching peripheral devices to a computer motherboard. ... This article or section does not adequately cite its references or sources. ... PCI Express (formerly known as 3GIO for 3rd Generation I/O, not to be mistaken with PCI-X) is an implementation of the PCI computer bus that uses existing PCI programming concepts and communications standards, but bases it on a much faster serial communications system. ... This is a list of device bandwidths: the channel capacity (or, more informally, bandwidth) of some computer devices employing methods of data transport is listed by bit/s, kilobit/s (kbit/s), megabit/s (Mbit/s), or gigabit/s (Gbit/s) as appropriate and also MB/s or megabytes per...

External links

• EISA bus technical summary
• "EISA System Architecture" published by Mindshare (pdf)
• Intel EISA Controllers

This article was originally based on material from the Free On-line Dictionary of Computing, which is licensed under the GFDL. This article or section does not adequately cite its references or sources. ... This article or section does not cite any references or sources. ... This article or section does not adequately cite its references or sources. ... 64-bit PCI expansion slots inside a Power Macintosh G4 The Peripheral Component Interconnect, or PCI Standard (in practice almost always shortened to PCI) specifies a computer bus for attaching peripheral devices to a computer motherboard. ... For other meanings of PCI, see PCI (disambiguation). ... PCI Express (formerly known as 3GIO for 3rd Generation I/O, not to be mistaken with PCI-X) is an implementation of the PCI computer bus that uses existing PCI programming concepts and communications standards, but bases it on a much faster serial communications system. ... // PC/104 PC/104 (or PC104) is an embedded computer standard controlled by the PC/104 Consortium, that defines both a form factor and computer bus. ... This article or section does not cite its references or sources. ... The PCMCIA is the Personal Computer Memory Card International Association, an industry trade association that creates standards for notebook computer peripheral devices. ... Low Pin Count interface IT8705F. Involved in fan speed control, floppy and keyboard management, smart card reader, MIDI interface and many other tasks (described in [1]). The Low Pin Count bus, or LPC bus, is used on PC-style personal computers to connect low-bandwidth devices to the CPU, such... Universal Serial Bus (USB) is a serial bus standard to interface devices. ... This article does not cite any references or sources. ... Bold text // “GFDL” redirects here. ...