Computer: Definition and History (Contd.)

Lin ZhongELEC101, Rice University

Electromechanical state

• A combination of electrical and mechanical states

• Electromagnetic relay to change mechanical state– Replay is a ON/OFF switch

Tabulating machine

• Invented by Herman Hollerith for 1890 U.S. Census because 1880 census took 7 years to tabulate (manually)– The origin of IBM

– Simple calculation (aggregation)

Turing Bombe

4

• Used to break Enigma during WW2

Rotor: 26 mechanical states corresponding to 26 lettersElectrical current flows through a series of rotors if their letter combination makes sense

5

6

Era of electrical states

ENIAC and vacuum tubes

Vacuum tube

7

8

State of vacuum tubes

DiodeTriode (transistor)

Problems with vacuum tube states

• Size• Power consumption• Speed

9

10

Era of charge states

Nobel Prize in Physics, 1956

11

Transistors at nanoscale

Sunlin Chou, “Extending Moore’s Law in the Nanotechnology Era” (www.intel.com).

12

Size matters

Smallest mass produced transistor 32nm

Intel 40041971

Moore’s Law

13

14

Computing: 60 years agoWiring ENIAC with a new program

15

Computing: TodayLiving among computers

“Computers” over $50 that serve me

A difference of 60 years• ENIAC (1946)

– $6 million in 2008 $– 17,468 vacuum tubes– 680 square feet– 27 tons– 15 KW power– Longest continuous period of

operation: 116 hours– 5000 operations per second

• Intel Core i7– ~$300– >730 million transistors– 263 mm²– A few ounces– <100W power– Runs forever– 76,383 MIPS (Million

Instruction Per Second)

16

A difference of 10 years

17

Samsung S5L8900 412MHz 128MB RAM/8-16GB Flash WiFi, Bluetooth 2.0, 3G 4.7 oz

Intel Pentium MMX 233MHz 64MB RAM/4GB Disk Ethernet 14 pounds

IBM Thinkpad 770 (1998)Apple iPhone (2008)

How about the next 10 years?

18

19

Other states• Resistance

– Negative differential resistance (NDR)• Molecules (Reed & Tour, 1999)• Resonant tunneling diodes (RTD)

• Presence/Absence of electrons– Quantum dots (nanoscale trap)

• Spin of electrons– Spintronics

20

Molecular conformation state

Collier et al, 2000

More videos about computer history

21

http://www.youtube.com/user/ComputerHistory