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Comparison of Intel Microprocessor8086, 386, 486, Pentium II

by Hong Li

Rivier College, CS699A Professional Seminar

Fall 1999

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Introduction

Computer technology has made incredible progress in the past half century. In 1945, there were no stored-program computers. Today, a few thousand dollars will purchase a personal computer that has more performance, more main memory, and more disk storage than a computer bought in 1965 for $1 million. During the first 25 years of electronic computers, both forces made a major contribution; but beginning in about 1970, computer designers became largely dependent upon integrated circuit technology. The late 1970s saw the emergence of the

microprocessor.

• What is a microprocessor ?

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The Intel 8086 Microprocessor

It is a 16-bit microprocessor chip available in speeds of 8MHz, 10MHz, and 12MHz.

It can address 1 Mb of data with only 16-bit address. This is accomplished by segmenting memory into separate 64K groups of data. Hardware and instructions integral to the 8086 control each 64K group.

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The Intel 8086 Microprocessor (continued)

• Memory Structure• Data storage in 8086 memory• Paragraphs• Program Segmentation and Segment Registers• Hardware Registers• Flags• Input/Output (I/O) Structure

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Intel 386 Microprocessor

It is an entry-level 32-bit microprocessor designed for single-user applications and operating systems such as MS-DOS and Windows.Base Architecture the Intel 386 consists of three major components:

• a central processing unit (CPU) • a memory management unit

-- segmentation unit -- the paging mechanism the Intel has two modes of operation: Real Address Mode

(Real Mode), and Protected Virtual Address Mode (Protected Mode).

• a bus interface

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Intel 386 Microprocessor (continued)Registers

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Intel 386 Microprocessor (continued)

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Intel 386 Microprocessor (continued)

• Instruction Set

The instruction set is divided into nine categories of operations

• Addressing Modes

The Intel 386 provides a total of 11 addressing modes for instructions to specify operands

• Memory organization – I/O Space– Real Mode Architecture – Protected Mode Architecture

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Intel 486 microprocessor

The Intel 486 CPU offers the highest performance for DOS, OS/2, Windows, and UNIX system V/Intel 386 applications. Its 100% binary compatible with the Intel 386 CPU.

Architectural Overview Real Mode Architecture. Protected Mode Architecture On-Chip Cache

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Pentium II Microprocessor

The Pentium II processor features and benefits can enhance user’s computing experience:

Introduction, Product Highlights,Dynamic Execution Technology, Intel MMX Technology, Thesting and Performance Monitioring Features.

Introduction Product Highlights Testing and Performance Monitoring Features

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Summary The Intel 8086 It is a 16-bit architecture, with

all internal registers 16 bits wide. The Intel 80386 were included a 32-bit data bus

structure and the ability to address up to 4GB of memory.

The Intel 80486 was a 32-bit data bus structure, and the ability to address up to 64GB of memory.

The Pentium II processor was a 7.5 million-transistor, it incorporates the Pentium pro and the Intel MMX technology, which is designed specifically to process video, audio and graphics data efficiently.

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References:

• --http://www.tasc.com/products/horizonmaster/HTML/irm/in/intel/init/html/intel486.htm• --http://www.tasc.com/products/horizonmaster/HTML/irm/in/intel/init/html/intel386.htm• --http://www2.eng.cam.ac.uk/~dmh/d7/resource/intro/tsld012.htm• --http://www2.eng.cam.ac.uk/~dmh/d7/resource/intro/tsld013.htm• --http://developer.intel.com/design/processor/future/roadmap.htm• --http://developer.intel.com/design/processor/future/overview.htm• --http://intel.com/pentiumii/xeon/home.htm• --http://intel.com/PentiumIII/Xeon/home.htm

• David A. Patterson & John L. Hennessy, "Computer Architecture a Quantitative Approach,“ 2nd edition, pp. 1-3, pp. D1- D14.

• "Intel Microprocessor: Volume I", 1994, Pg 1-1---1-66, Pg 3-1---3-30.• "Intel Microprocessor: Volume II", 1994, Pg 2-2, Pg 2-2---2-85.• Robert S. Lai, "Writing MS-DOS Device Drivers", 2nd edition, The Waite

Group, pp. 461- 474.