Lecture 1

History Of ComputersGenerations Of Computers

Assignment # 1

Pre-Computing

Counting on fingers Counting Pebbles Counting marks on the walls Counting marks on the bones Counting marks in the sand

Computer Prehistory

Abacus(3000 B.C)Considered to be the Original Counting

Device.Simple device used to perform calculationsSlide the Beads up and down on the rods to

add and subtract.Relies on training, knowledge of user

Abacus . 3000 B.C

beads on rods to count and calculate

still widely used in China.

Computer Prehistory

Pascaline(1623 – 1662) Invented by Blaise Pascal He invented it to help his father in tax

collection.Gear-driven machine performing whole-

number addition & subtractionPascal was only man who could make repairs

Computer Prehistory

17th Century - Pascaline

Computer Prehistory Jacquard’s loom(1801)

Wove cloth, silk, and other materialsKnots passing through the holes in cards

created patterns woven into fabric

Early Computer Attempt

Charles Babbage(1793 – 1871) Considered to be Father of Computers because of

his Impressive designs for

Difference Engine

Analytical Engine

Difference Engine

huge calculator, steam driven & never finished

Early Computer Attempt

Analytical engineDesigned by Charles Babbage Similar to early computers

Could store up to 1000 50-digit numbers Could run more complex programs than early

machines at a rate of 60 Additions/sec accurate to six decimal places

Early Computer Attempt

Analytical engineSteam power turned

handles Wouldn’t need humans

to run

Design would cover the area of a football field.

Binary Machines

Konrad Zuse develops Z1(1936)

First automatic calculator based in binaryFirst Programmable computer designed to

solve complex engineering Equations.

Binary Machines

1936 --- Konrad Zuse develops Z1Contained memory to remember 64 numbersEach multiplication took 5 seconds

Electronic Computers

ABC Computer(1939-1942)First electronic, digital computerBuilt by John Atanasoff & Clifford BerryPerformed complicated mathematical

computationsOriginal notes for design written on the back

of a cocktail napkin

Electronic Computers

ABC Computer(1939-1942)Weighed 800lbs, used 300+ vacuum tubes, &

1 mile of wireEach calculation took 15 seconds

Electronic Computers

Mark I Computer(1944)Developed by Howard Aiken & IBMCould add, subtract, multiply and divide

Included subroutines to compute logarithms and trigonometric functions.

It had switches which when flipped back and forth, represented mathematical data.

Electronic Computers

Mark I ComputerWeighed 5 tons,

55’ long, 8’ highStored 72 numbers3 additions/second; 3 - 5 seconds per

multiplication

Electronic Computers

ENIAC Computer(1943-1946)Electronic Numerical Integrator and ComputerTo compute trajectory table for US army.Programs set by external switches and dials

Took weeks to physically reprogram machines

Electronic Computers

ENIAC ComputerWeighed 30 tons

17,460 vacuum tubes 5 million soldered joints

Performed 5000 additions, 357 multiplications or 38 divisions per second

Electronic Computers

ENIAC Computer ShortcomingsCould only store and manipulate a limited

amount of information.Programs were wired on boards.Thus, difficult to detect errors.

Electronic Computers

1953 701 released, IBM’s 1st computerStored 256 numbers in memoryOnly 19 ever made

Rented by businesses for $15,000 per month

IBM sold 1,800 IBM 650s, which worked with IBM punch card equipment, from 1954-1962

Electronic Computers

1953 701 released, IBM’s 1st computerPerformed 2200 multiplications per second

1st Generation Computers

EDVAC(1946-1952) Electronic Discreet Variable Automatic Computer Based on Stored Program Concept. Stored data in binary form.

UNIVAC(1951) Universal Automatic Computer First fully electronic digital computer built in the U.S. Use of vacuum tubes

1st Generation Computers

Advantages:These were the Fastest calculating devices of

that time. Disadvantages:

Too bulky in Size.Excessive Heat Generation.Non-portable.

2nd Generation

Used Transistors starting in 1956 Replaced vacuum tubes with Transistors, thus

making it faster, smaller and reliable. Advantages:

Less Heat Generation Smaller than 1st Generation Computers.

Disadvantages: Costly Manual Assembly of individual components

PDP-8 Minicomputer

In 1963,PDP-8 was launched.

Small computers for business and specific applications.

3rd Generation

Third Generation Computers used Integrated Circuits (chips).

Integrated Circuits are transistors, resistors, and capacitors integrated together into a single “chip”.

Advantages: Smaller in size, easily portable, no need of manual

assembly of individual components. Disadvantages:

Highly sophisticated technology required.

4th Generation

Over 30,000 components were integrated onto a single chip.

Performed 60,000instructions per second. The First Microprocessor (Intel 4004)

The 4004 had 2,250 transistors.108KhzCalled “Microchip” (Specialized chip for

memory and logic)

4th Generation

AdvantagesSmallest in size.Heat generation is negligible.Much faster in computations.Cheapest.

DisadvantagesHighly sophisticated technology required.

Birth of Personal Computers(1975)

MITS ALTAIR Could hold 256 numbers in

RAM Required TV for use as a

display Did not include any software

(even an OS) Owner had to put machine

together Cost $400 Small company, Microsoft,

formed by 2 college kids to sell BASIC compiler for Altair

Growth of the Home Computer

Apple I(1976) Could store 8192 numbers

(8KB) in memory Included keyboard, but

needed TV for display Cost $666.66 per machine Less powerful than Altair

but also less expensive and complicated.

Growth of the PC

Apple II(1977) Contained 4KB of

memory First personal computer

to include color graphics (included 16 colors!), but still needed TV for monitor

Built-in Keyboard

Player Enters the Market

IBM PC (1981) First PC fully built from off-the-shelf parts and

commercially available operating system

Player Enters the Market

IBM PC(1981) Used 4.77MHz processorDefault had16KB of memory, but could be

expanded to 256KBColor monitor was optionalCost $1565

Updated Computer Line

Apple IIe (1983)Used 1MHz processor Included 64KB of memoryCost $1400 per machineBecame one of the best selling computers of

all time

Personal Computer Revolution

Apple Lisa (1983) 1st GUI-based home computerUsed 5 MHz processor, 512KB of memory,

5MB hard drive12” monitorCost $9995Apple Macintosh released in 1984

Personal Computer Revolution

1983 – Apple Lisa released 1984 – Apple Macintosh released

Other Important Computer Dates

1983 – Intel releases 80386Speed---16MHz

1983 – 10 million computers used in US 1986 – 30 million computers used in US 1989 – Intel releases 80486

25MHzFirst Intel chip capable of multiprocessing

Pentium Series

In 1995 Pentium-Pro Microprocessor Windows 95 OS

In 1997 Intel announces Multimedia capabilities Pentium II(333MHz Speed)

In 1998 Windows 1998 OS.

In 1999 Pentium III (Graphics Friendly)

Assignment 1

Discuss the growth of PCs from year 2000 to 2005 in terms of Hardware improvement and Operating Systems.

Discuss Von-Neumann's Architecture.