1 Comparison of Intel Microprocessor 8086, 386, 486, Pentium II by Hong Li Rivier College, CS699A Professional Seminar Fall 1999

2 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 ?

3 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.

4 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

5 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

6 Intel 386 Microprocessor (continued) Registers

7 Intel 386 Microprocessor (continued)

8 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

9 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

10 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

11 Summary  The Intel 8086 It is a 16-bit architecture, with all internal registers 16 bits wide.  The Intel were included a 32-bit data bus structure and the ability to address up to 4GB of memory.  The Intel 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.

12 References: David A. Patterson & John L. Hennessy, "Computer Architecture a Quantitative Approach,“ 2 nd edition, pp. 1-3, pp. D1- D14. "Intel Microprocessor: Volume I", 1994, Pg , Pg "Intel Microprocessor: Volume II", 1994, Pg 2-2, Pg Robert S. Lai, "Writing MS-DOS Device Drivers", 2 nd edition, The Waite Group, pp