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The 80286 performs at twice the speed of its predecessor (the Intel 8086) per clock cycle, and is able to address up to 16 megabytes of RAM, in contrast to the 1MB the 8086 can work with. On DOS machines this additional RAM capability can only be utilised via extended memoryExtended memory refers to memory above the first megabyte of address space in an IBM PC with an 80286 or later processor. Extended memory is not directly available in real mode, only through EMS, UMB, XMS, or HMA; only applications executing in protected emulation, however few 286-based computers ever saw more than a megabyte of RAM.

The 286 was designed to run multitasking applications, including Communications (such as automated PBXs), real-time process control , and multi-user systems.

Despite their market popularity, few desktop computers with a 80286 CPU still remain in use today.

The 286's successor was the 32-bit32-bit is a term applied to processors, and computer architectures which manipulate the address and data in 32- bit chunks. It is also a term given to a generation of computers where 32-bit processors were the norm. The range of integer values that can be Intel 80386The Intel 80386 is a microprocessor which was used as the central processing unit (CPU) of many personal computers from 1986 until 1994 and later. During its design phase the processor was code-named simply P3 the third-generation processor in the x86 lin.

An interesting feature of this processor is that it was the first x86 processor capable of switching from real modeReal mode is an operating mode of 80286 and later x86-compatible CPUs. Real mode is characterized by a 16 bit segmented memory address space (meaning that only 1 MB of memory can be addressed), direct software access to BIOS routines and peripheral hardwa to protected modeProtected mode (sometimes abbreviated pmode is an operational mode of x86-compatible CPUs of the 80286 series or later. Protected mode has a number of new features designed to enhance multitasking and system stability, such as memory protection, a paging, enabling the use of all system memory as a single block, and allowing certain degree of protection of the memory zones used by applications. However, the 286 couldn't revert back to real mode, being this the reason why the protected mode wasn't widely used; not until the appearance of the 386, which could go to and back from protected mode, unlike the 286.

External links

• Linux on 286 laptops and notebooks