X86: Difference between revisions

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'''x86''' is the [[instruction set architecture]] (ISA) for the Intel 8086 and 8088 chips, 16-bit microprocessors first produced in 1978<ref name="Intel Museum">{{cite web
'''x86''' is the [[instruction set architecture]] (ISA) for the Intel 8086 and 8088 chips, 16-bit microprocessors first produced in 1978<ref name="Intel Museum">{{cite web
|url="http://www.intel.com/museum/online/hist_micro/hof/index.htm"|title="Intel Museum: The Microprocessor Hall of Fame"|retrievedate=2007-04-09}}</ref>  The 8088 chip was used in the very first incarnation of an [[IBM compatible PC]] introduced by IBM in 1983.
|url="http://www.intel.com/museum/online/hist_micro/hof/index.htm"|title="Intel Museum: The Microprocessor Hall of Fame"|retrievedate=2007-04-09}}</ref>  The cheaper 8088 chip (which contained an 8-bit multiplexed bus, as opposed to a full 16-bit bus in the 8086) was used in the very first incarnation of an [[IBM compatible PC]] introduced by IBM in 1983.


The x86 instruction set achieved historic status due to a remarkable decision, made jointly by the designers of the original IBM compatible PC.  They decided to maintain backward compatibility in both software and hardware, and to maintain it ''indefinitely'',  Thus, all subsequent "Intel" processor chips in the 86-styled family would always execute the original '''x86''' instructions, and all subsequent Microsoft operating systems would execute program which ran on the original [[IBM compatible PC]].   
The '''x86''' instruction set achieved historic status due to a remarkable decision, made jointly by the designers of the original IBM compatible PC.  They decided to maintain backward compatibility in both software and hardware, and to maintain it ''indefinitely'',  Thus, all subsequent "Intel" processor chips in the 86-styled family would always execute the original '''x86''' instructions, and all subsequent Microsoft operating systems would execute program which ran on the original [[IBM compatible PC]].   


This decision to maintain backward compatibility of hardware and software laid the groundwork for the subsequent success of the x86 family of microprocessors, and the IBM compatible PCs which contain them.
This decision to maintain backward compatibility of hardware and software laid the groundwork for the subsequent success of the x86 family of microprocessors, and the IBM compatible PCs which contain them.

Revision as of 11:53, 9 April 2007

x86 is the instruction set architecture (ISA) for the Intel 8086 and 8088 chips, 16-bit microprocessors first produced in 1978[1] The cheaper 8088 chip (which contained an 8-bit multiplexed bus, as opposed to a full 16-bit bus in the 8086) was used in the very first incarnation of an IBM compatible PC introduced by IBM in 1983.

The x86 instruction set achieved historic status due to a remarkable decision, made jointly by the designers of the original IBM compatible PC. They decided to maintain backward compatibility in both software and hardware, and to maintain it indefinitely, Thus, all subsequent "Intel" processor chips in the 86-styled family would always execute the original x86 instructions, and all subsequent Microsoft operating systems would execute program which ran on the original IBM compatible PC.

This decision to maintain backward compatibility of hardware and software laid the groundwork for the subsequent success of the x86 family of microprocessors, and the IBM compatible PCs which contain them.

References

  1. ["http://www.intel.com/museum/online/hist_micro/hof/index.htm" "Intel Museum: The Microprocessor Hall of Fame"].