chapter 1 introduction to microprocessors

8/7/2013

1

INTRODUCTION TO

MICROPROCESSORChapter 1

STUDENT LEARNING OUTCOMES

Upon completion of this topic, you should be able to:

Explain basic components of a computer system using block

diagram.

Describe evolution of microprocessor.

Define the meaning of the term Nibble, Byte, Word, Long

Word.

Explain fetching and execution cycles.

Explain internal structure and basic operation of a

microprocessor.

Explain bus system.

Explain microprocessor clock system.

Identify the examples of microprocessor

8/7/2013

2

CPU

Memory

I/O unit

Central Processing Unit

(CPU)

Input Unit Output Unit

Main MemorySecondary Memory

BASIC COMPONENTS OF A COMPUTER SYSTEM

Central Processing Unit (CPU)

The hardware within a computer system which carries out the

instructions of a program by performing the basic

arithmetical, logical and I/O operations of the system.

On large machines CPUs require one or more printed circuit

boards. On personal computers and small workstations, the

CPU is housed in a single silicon chip called a microprocessor.

DEFINITIONS

8/7/2013

3

Central Processing Unit (CPU)

In the past, CPUs were mechanical, electromechanical or

transistor circuit based. Since the 1970s, technology allowed

the CPU to be implemented in a single IC package, called the

microprocessor.

The term CPU and microprocessor has often been mixed up

today. However, the CPU actually refers the core of the

microprocessor.

DEFINITIONS (CONT)

It is a multipurpose, programmable device that accepts

digital data as input, processes it according to instructions

stored in its memory, and provides results as output.

A microprocessor is an electronic device that consists of

millions (or billions) of transistors packed into one IC.

Its function is to execute instructions in the form of

programs, calculate and store its results.

Microprocessors are used widely in our everyday lives.

WHAT IS A MICROPROCESSOR

8/7/2013

4

Everyday items that use microprocessors

P is a complex, powerful device:

Able to process huge amounts of data.

Built using transistors etched on silicon die.

Needs external components to support operation.

Microcomputer system support P operations.

The microprocessor can be used to perform complex

operations by giving it instructions.

These instructions are called programs.

Programs are loaded into memory, and are executed line-by

line by the microprocessor.

MORE ABOUT THE MICROPROCESSOR

8/7/2013

5

Rapid pace of information technology is

due to introduction of new

microprocessors.

Most of us think of desktop computers

PC

Laptop

Mainframe

Server

Maybe at most handheld computer (PDA).

In this course, we will look at another type

of computing system which is far more

common that you ever imagined

COMPUTING SYSTEMS

Servers:

Big, expensive, available 24x7 (read 24 by 7 or 24 hours

a day, 7 days a week. Mainframes are old servers made by

IBM.

Desktops:

computers on your desk

Laptops:

computers you carry in your bag

PDA (personal digital assistants):

computers you carry in your pocket

Embedded systems:

computers that dont look like computers!

An embedded system is a type of computer

CLASSIFICATION OF COMPUTERS

8/7/2013

6

Account for >99% of new

microprocessors

Consumer electronics

Vehicle control systems

Medical equipment

Sensor networks

Desktop processors (Intel Pentium,

AMD Athlon, PowerPC, etc)

combined is only 1%.

EMBEDDED SYSTEMS

Simple definition: Computing systems embedded within

electronic devices.

Nearly any computing system other than a desktop

computer.

Designed to perform a specific function.

Billions of units produced yearly, versus millions of desktop

units.

Take advantage of application characteristics to optimize the

design.

As electrical or electronics engineers, you may be required

to design an embedded system.

But you BUY (not design) a general purpose computer.

EMBEDDED SYSTEMS

8/7/2013

7

GENERAL PURPOSE COMPUTING VS

EMBEDDED SYSTEMS

GENERAL PURPOSE EMBEDDED

Intended to run a fully general set

of applications

Runs a few applications often

known at design time

End-user programmable Not end-user programmable

Faster is always better Operates in fixed run-time

constraints, additional performance

may not be useful/valuable

Differentiating features:

Speed (need not be fully predictable)

Software compatibility Cost (eg RM3k vs RM5k per

laptop)

Differentiating features:

Power Cost (eg RM2 vs RM2.50) Speed (must be predictable)

IC MANUFACTURING

PROCESSFrom Sand to Silicone

8/7/2013

8

MANUFACTURING PROCESS


8/7/2013

9


http://www.nikon.com/products/precision/soc

iety/story0202/index.htm


8/7/2013

10

Has undergone significant improvements:

4 generations until now.

Tied to development of electronics, semiconductors.

Vacuum

Tube

Transistor ICBetter IC

technology

G1 G2 G3 G4

HISTORY OF COMPUTERS

First Generation (1954-1956):

Vacuum Tubes as switches.

Magnetic drums as memory.

Very big, unreliable, slow.

Examples:

ENIAC (Electronic Numerical Integrator &

Computer),

UNIVAC (UNIVersal Automatic Computer).


8/7/2013

11

Electronic Numerical Integrator and Computer (ENIAC)

Vacuum Tubes

FIRST GENERATION COMPUTERS

Second Generation (1956-1963):

After invention of transistors.

Smaller, faster, cheaper.

Limited to military and business use.


8/7/2013

12

Transistor circuit

Vacuum tube circuit

SECOND GENERATION COMPUTERS

Third Generation (1964-1971):

After invention of Integrated Circuits (IC).

Many transistors can be packed into IC birth of

microprocessors.

Early microprocessors: Intel 8008, Intel 4004.

Medium Scale Integration (MSI) and Large Scale Integration

(LSI) devices.

Description of SSI, MSI, LSI, VLSI

HISTORY OF MICROPROCESSORS

8/7/2013

13

EARLY INTEL MICROPROCESSORS

Laptop

PC

THIRD GENERATION COMPUTERS

8/7/2013

14

Fourth Generation (1971-now):

Improvements in IC technology, P design.

More transistors more processing power.

Very Large Scale Integration (VLSI).

- Intel Montecito Itanium: 1 bln. transistors.

Reduced Instruction Set Computers (RISC).

32, 64-Bit microprocessors.


FOURTH GENERATION COMPUTERS

8/7/2013

15

COMPARISON BETWEEN COMPUTER

GENERATIONS

Computer Speed Memory Cost

UNIVAC

(1st Gen.)

1.3 kHz 1 MB $1.6 million

IBM 1401

(2nd Gen.)

2.2 kHz 1.4 kB $47,900

DEC PDP-8

(3nd Gen.)

1 MHz 6 kB $20,000

Pentium III

(4th Gen.)

500 MHz 128 MB $700

Definition: A complete electronic system built around the microprocessor to support the microprocessor operation.

May consist of CPU, memory, I/O (disk drives, keyboard, mouse), system bus, and supporting circuitry.

CPU as the brain controls actions of all components.

MICROPROCESSOR SYSTEMS

8/7/2013

16

MICROPROCESSOR SYSTEMS - PC

ROM

Keyboard Mouse HDD

Floppy RAM

CD-ROMSupporting

CircuitryCPU

MICROPROCESSOR SYSTEMS -CALCULATOR

Keypad

Memory

Power Supply LCD DisplayCPU

8/7/2013

17

In general, a computer system consist of the following

elements:

COMPUTER SYSTEM-SIMPLIFIED VIEW

Unidirectional:

Signals flow in

one direction.

Bidirectional:

Signals flow in

both direction

(one at a time).

A P-based system consists of many components:

CPU.

Memory.

I/O: disk drives, keyboard, mouse.

System Bus.

All components communicate using System Bus.

Communication highway for all components.

A group of wires is called bus.

Contains:

Data bus.

Address bus.

Control bus.

SYSTEM BUS

8/7/2013

18

Bidirectional (2 ways) bus.

Transfer data to/from the CPU

SYSTEM BUS DATA BUS

CPU

R/WControl

signal is

READ

Input

(from

Memory or

I/O devices)

Data bus

CPU

R/WControl

signal is

WRITE

Output

(to Memory

or I/O

devices)

Data bus

Example:

Motorolla 68000 microprocessor has 8 bits data bus,

thus:

Data size n = 8 bits,

Data lines/bus are labelled Dn : D0, D1, .. D6, D7

The size of data bus is determined by the number of lines

(bits) which is also called data size.

SYSTEM BUS DATA BUS

8/7/2013

19

Single direction (unidirectional / 1 way) bus

Transfer the address data code to memory or devices.

SYSTEM BUS ADDRESS BUS

CPU

Memory

I/O Devices

CPU to other

elementsADDRESS BUS

Example: Motorolla 68000 has 16 bits of address bus:

n = 16 bits (Size of address bus)

Address bus is labelled An : A0, A1, .. A14, A15 216 = 65536 CPU can handle or address 65536 single cells (each

cell has 8 bits data size) of memory.

SYSTEM BUS ADDRESS BUS

8/7/2013

20

In other words, 16 bit address lines can represent 65536 memory location

0 to 65535 locations, addressed as 0000h to FFFFh

16 address lines, then the size of the memory is equal to 216 = 64Kbyte.

8-bit address bus

Address bus labeled

A0, A1,..A7

Memory location

28 = 256

Address

00h to FFh

Size of the memory

28 = 256 byte

EXAMPLE 1

8/7/2013

21

32-bit address bus

Address bus labeled

A0, A1,..A31

Memory location

232 = 4,294,967,296

Address

00000000h to FFFFFFFFh

Size of the memory

232 = 22 . 230 = 4GB

EXAMPLE 2

Control all the activities of the elements.

Regulate information transfer, interrupts, error signals.

Ensures that only one IC is active at a time to avoid a bus

conflict caused by two ICs writing different data to the

same bus.

SYSTEM BUS CONTROL BUS

8/7/2013

22

Master of all components.

Silicon chip that works as heart of the system.

Job:

Get instructions from memory.

Execute instructions.

Perform calculations (may use math co-processor).

Control bus operations.

THE CPU

CPU consists of:

ALU (Arithmetic/Logic Unit):

Performs arithmetic/ logic computations.

The number of bits is a most important factor

Determining the capabilities of the processor

Typical sizes:

4 bits (very small microcontroller: remote controllers)

8 bits (microcontrollers: 68HC05, 8051, PIC)

16 bits (low-end microprocessors: Intel 8086)

32 bits (most popular size today: Pentium, PowerPC, 68000,

ARM, MIPS)

64 bits (servers: IBM POWER & PowerPC G5, AMD Opteron,

Intel Itanium

CU (Control Unit):

Responsible to retrieve instructions, analyze, then execute.

THE CPU

8/7/2013

23

Data Register

Temporarily stores data for immediate processing

Address Register

Temporarily stores address of data in memory

Instruction Register

Stores the instruction currently being executed or decoded

Includes ALU operation and address of operand

Program Counter

Keeps track of program execution

Address of next instruction to read from memory

May have auto-increment feature or use ALU

Some manufacturers call this register the Instruction Pointer (IP)

Status Register

Stores the result of the current data manipulation (negative,

zero etc)

CPU REGISTERS

The number of bits of a microprocessor dictates the maximum

data width of the memory address and data units.

For example a 4-bit microprocessor can only address up to 16

memory cells and process a maximum data size of 4 bits width.

Microprocessor Bits Clock Speed Year Application

Intel 4004 4 740kHz 1971-1981 General Computing

HP Saturn 4 640kHz 1980s Calculator

Intel 8008 8 0.5-0.8MHz 1972-1983 General Computing

Zilog Z80 8 2.5MHz 1976-present Desktop computers,

industrial, consumer

electronics

Motorola

68000

16 8-20MHz 1979-present Multi-user computers,

General computing,

arcade games, embedded

controller

MICROPROCESSOR IN BITS

8/7/2013

24

Microprocessor Bits Clock Speed Year Application

Intel 80286 16 6Mhz-25Mhz 1982-1990s General computing,

embedded systems

Intel Pentium 32 Varies 1993-present General computing,

embedded systems

MIPS R3000 32 33MHz 1988 General computing,

embedded systems

Sony Playstation

AMD Athlon 64 64 1.0GHz

3.2GHz

2003 General Computing

Intel Core 2 64 1.06GHz

3.33GHz

2006 -

present

General Computing

MICROPROCESSOR IN BITS

MICROPROCESSOR

VS

MICROCONTROLLER

8/7/2013

25

THE MICROPROCESSOR SYSTEM

THE MICROCONTROLLER SYSTEM

8/7/2013

26

Microprocessor Microcontroller

A chip that contains only the

processor

A chip that contains all the

components of a computer

processor components of a

computer processor, memory and

input/output

Need other chips to make a

working system

Less flexibility

More flexible Less component count in system

Can have very few I/O or many I/O

devices using the same

processor chip

Less powerful

SUMMARY : MPU VS MCU

Computers are binary machines which can only accept inputs of 1s

or 0s.

Data is also stored in streams of 1s and 0s.

Binary (base 2)

0000, 0001, 0010, 0011

Octal (base 8)

0, 1, 2, 3, 4, 5, 6, 7, 10, 11 ,12 16, 17, 20

Hexadecimal (base 16)

0, 1, 2, 3, 8, 9, A, B, C, D, E, F, 10, 11, 12, 1E, 1F, 20

Decimal (base 10)

1, 2, 3, 4, 5, 8, 9, 10, 11

In computing, the microprocessor uses binary data and normally

relate the data to human interface in hexadecimal form. For display

and printing purposes, hexadecimal is much more practical.

NUMBERING SYSTEMS IN COMPUTERS

8/7/2013

27

The capacity of a microprocessor is normally referred to how

many bits of data can be handled at one time, or what is the

memory size .

A bit is used to describe the data of a signal, it could be 1 or

0. In other words, each bit has two states.

Data size is a mean of measure to determine how much data

can be stored in a single cell of memory.

Data type :

Bit (B)

Nibble

Word (W)

Longword (L)

DATA SIZE IN COMPUTING

There is a standardization of data sizes.

Bit (basic unit)

Nibble (or half byte)

One nibble is 4 bits long. Range from 0000 1111. (0 15)

Eg. 0010, 0001, 1100, 1111

Byte

One byte is 8 bits long.

Range from 00000000 11111111 (0 255)

Eg. 00000011, 00001111, 11100011

Word

One word is two bytes long.

Longword

One longword is two bytes long.


8/7/2013

28

Words and longwords are normally used to describe instruction size,

from a microprocessor perspective as opposed to disk storage

system which uses megabytes and gigabytes.



8/7/2013

29

A single cell sized 1 bit can store either logic-0 or logic-1. In

other word, two different situations can be stored or

represented. Thus the range of data is 0 1.

Data size: n = 1

Data capacity : 2n = 21 = 2

Range : 0 1

A single cell sized 4 bit (Nibble) can store 16 possible situations.

Data size: n = 4

Data capacity : 2n = 24 = 16

Range : 0 - 15

EXAMPLE

The processor executes instructions one-by-one according to the

sequence found in memory

Everything is controlled by, what else, the control unit in the CPU.

To execute an instruction, the processor must fetch it from memory.

The complete steps the processor takes to execute one instruction is

the instruction cycle or the fetch-execute instruction is the

instruction cycle or the fetch execute cycle

FETCH AND EXECUTE CYCLE

8/7/2013

30

CPU executes instructions in endless fetch, decode, execute cycles.

It only knows how to do three things:

Fetch instructions from somewhere.

Analyze instruction, get more data if necessary.

Execute instruction.

Keeps track of instruction using Program Counter (PC):

Tells CPU location of next instruction.

CPE EXECUTION CYCLE

Reset

Fetch

Decode

Execute

FETCH, DECODE, EXECUTE

8/7/2013

31

Instruction #1

Instruction #1

$1001

$1009

$1008

$1007

$1006

$1005

$1004

$1003

$1002

$1000

Instruction #2

Instruction #2

Empty

Empty

Empty

Data #1

Data #2

Data #3

CPU Memory

Program Counter

$1000

Control


Data Registers

CPU gets

instruction address

from PC

FETCH STEP 1

Program Counter

Instruction #1

$1001

$1009

$1008

$1007

$1006

$1005

$1004

$1003

$1002

$1000

Instruction #1

Instruction #2

Instruction #2

Empty

Empty

Empty

Data #1

Data #2

Data #3

$1000

Control

CPU Memory


Data Registers

CPU outputs

instruction address

through Address Bus

$1000

Address Bus

FETCH STEP 2

8/7/2013

32

Program Counter

Instruction #1

$1001

$1009

$1008

$1007

$1006

$1005

$1004

$1003

$1002

$1000

Instruction #1

Instruction #2

Instruction #2

Empty

Empty

Empty

Data #1

Data #2

Data #3

$1000

Control

CPU Memory


Data Registers

Memory gets the

instruction and

sends in to CPU

using Data Bus.

Instruction #1

Data Bus

FETCH STEP 3

Program Counter

Instruction #1

$1001

$1009

$1008

$1007

$1006

$1005

$1004

$1003

$1002

$1000

Instruction #1

Instruction #2

Instruction #2

Empty

Empty

Empty

Data #1

Data #2

Data #3

$1000

Control

CPU Memory

Instruction #1


Data Registers

CPU stores

instruction in


FETCH STEP 4

8/7/2013

33

Program Counter

Instruction #1

$1001

$1009

$1008

$1007

$1006

$1005

$1004

$1003

$1002

$1000

Instruction #1

Instruction #2

Instruction #2

Empty

Empty

Empty

Data #1

Data #2

Data #3

$1002

Control

CPU Memory

Instruction #1


Data Registers

After instruction has

been loaded, CPU

updates Program

Counter.

FETCH STEP 5

Program Counter

Instruction #1

$1001

$1009

$1008

$1007

$1006

$1005

$1004

$1003

$1002

$1000

Instruction #1

Instruction #2

Instruction #2

Empty

Empty

Empty

Data #1

Data #2

Data #3

$1002

Control

CPU Memory

Instruction #1


Data Registers

CPU analyzes

instructions before

executing it.

Type of instruction.

Does the instruction require any data to perform calculations?

Where are the data located?

DECODE STEP 1

8/7/2013

34

Program Counter

Instruction #1

$1001

$1009

$1008

$1007

$1006

$1005

$1004

$1003

$1002

$1000

Instruction #1

Instruction #2

Instruction #2

Empty

Empty

Empty

Data #1

Data #2

Data #3

$1002

Control

CPU Memory

Instruction #1

Data #1


Data Registers

CPU puts data inside

internal data

registers and execute

instructions.

EXECUTE STEP 2

Program Counter

Instruction #1

$1001

$1009

$1008

$1007

$1006

$1005

$1004

$1003

$1002

$1000

Instruction #1

Instruction #2

Instruction #2

Empty

Empty

Empty

Data #1

Data #2

Data #3

$1002

Control

CPU Memory

Instruction #1

Data #1

Result #1


Data Registers

If instruction wants to

write data to memory,

CPU puts its data and

address on the bus.

$1005

Address Bus

Result #1

Data Bus

EXECUTE STEP 3

8/7/2013

35

Program Counter

Instruction #1

$1001

$1009

$1008

$1007

$1006

$1005

$1004

$1003

$1002

$1000

Instruction #1

Instruction #2

Instruction #2

Empty

Result #1

Empty

Data #1

Data #2

Data #3

$1002

Control

CPU Memory

Instruction #1

Data #1

Result #1


Data Registers

Memory receives

instructions and puts

data in the location.

EXECUTE STEP 4

On program start:

0. Load the program counter (PC) with the address of the first

instruction

Fetch phase:

2. Read the instruction and put it into the instruction register (IR)

3. Control unit decodes the instruction; updates the PC for the next

instruction

Execute phase:

3. Find the data required by the instruction.

4. Perform the required operation.

5. Store the results.

6. Repeat from Step 1.

FETCH AND EXECUTE IN SUMMARY

8/7/2013

36

Name the 4 computer generations and the technological

breakthroughs that caused them to happen.

Draw the microprocessor system and explain the functions

of each component in the system.

TUTORIAL QUESTION

chapter 1 introduction to microprocessors

Documents