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Computer Science (Paper-II)
3. Introduction to Intel X-86 Family
Family members of Intel X-86 Family
1. 8086:
- 16 bit microprocessor , introduced in 1978 .Its ALU ,
- 80186 is an improved version of 8086. In addition to 16 bit CPU, it has
programmable peripheral (I/O) devices integrated in same package.
2. 80286:
- 16 bit microprocessor, introduced in 1982. Designed for multitasking / operating
systems.
- 16 bit data bus and 24 bit address bus.
- In 1984, IBM introduced PC/AT version (Personal Computer/Advanced
Technology) version of its PC using 80286.
- 286 was having real and protected modes of operation. In real mode, the
processor can address only 1 M Byte , whereas in protected mode , it can address
16 M Bytes of memory .
- Ability to work up to 1 GByte of virtual memory and hardware multitasking
- The program written for 8086 can run on 80286, in real mode.
3. 80386:
- 32 bit microprocessor, introduced in 1985.
- 80386 is a logical extension of 80286. It is more pipelined.
- The instruction set of 80386 is a superset of 80286
- It has 32 bit data bus and 32 bit address bus. It can address 4 GBytes memory.
- The 386 can operate in one of the two modes. : 1) Paged mode 2) Non-paged
mode.
- In paged mode, The 386 switches the paging unit and then the segment unit. the
paged mode allows memory pages of 4 KB each to be swapped in and out from
Disk. In nonpaged mode It operates similar to 286.
4. 80486:
- 32 bit microprocessor, introduced in 1989.
- 32 bit address bus and 32 bit data bus.
- Th 486 is a large integral circuit which contains a fast built-in math coprocessor,
a memory management unit, and a 8 Kbyte cache memory.
- 80486 have DX and SX versions.
- The 486 achieves its high speed operation from it's faster clock speed. Internal
pipeline lined architecture and the use of reduced instruction set computing RISC
to speed up internal microcode.
- 486 also has DX2 and DX4 versions with double and triple clock speed.
Computer Science (Paper-II)
3. Introduction to Intel X-86 Family
Family members of Intel X-86 Family
1. 8086:
- 16 bit microprocessor , introduced in 1978 .Its ALU ,
- 80186 is an improved version of 8086. In addition to 16 bit CPU, it has
programmable peripheral (I/O) devices integrated in same package.
2. 80286:
- 16 bit microprocessor, introduced in 1982. Designed for multitasking / operating
systems.
- 16 bit data bus and 24 bit address bus.
- In 1984, IBM introduced PC/AT version (Personal Computer/Advanced
Technology) version of its PC using 80286.
- 286 was having real and protected modes of operation. In real mode, the
processor can address only 1 M Byte , whereas in protected mode , it can address
16 M Bytes of memory .
- Ability to work up to 1 GByte of virtual memory and hardware multitasking
- The program written for 8086 can run on 80286, in real mode.
3. 80386:
- 32 bit microprocessor, introduced in 1985.
- 80386 is a logical extension of 80286. It is more pipelined.
- The instruction set of 80386 is a superset of 80286
- It has 32 bit data bus and 32 bit address bus. It can address 4 GBytes memory.
- The 386 can operate in one of the two modes. : 1) Paged mode 2) Non-paged
mode.
- In paged mode, The 386 switches the paging unit and then the segment unit. the
paged mode allows memory pages of 4 KB each to be swapped in and out from
Disk. In nonpaged mode It operates similar to 286.
4. 80486:
- 32 bit microprocessor, introduced in 1989.
- 32 bit address bus and 32 bit data bus.
- Th 486 is a large integral circuit which contains a fast built-in math coprocessor,
a memory management unit, and a 8 Kbyte cache memory.
- 80486 have DX and SX versions.
- The 486 achieves its high speed operation from it's faster clock speed. Internal
pipeline lined architecture and the use of reduced instruction set computing RISC
to speed up internal microcode.
- 486 also has DX2 and DX4 versions with double and triple clock speed.
