1. Computer: Definition and History (Contd.) Lin Zhong ELEC101, Rice University

2. Electromechanical state A combination of electrical and mechanical states Electromagnetic relay to change mechanical state – Replay is a ON/OFF switch

3. 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)

4. Turing Bombe 4 Used to break Enigma during WW2 Rotor: 26 mechanical states corresponding to 26 letters Electrical current flows through a series of rotors if their letter combination makes sense

5. 5

6. 6 Era of electrical states ENIAC and vacuum tubes

7. Vacuum tube 7

8. 8 State of vacuum tubes Diode Triode (transistor)

9. Problems with vacuum tube states Size Power consumption Speed 9

10. 10 Era of charge states Nobel Prize in Physics, 1956

11. 11 Transistors at nanoscale Sunlin Chou, “Extending Moore’s Law in the Nanotechnology Era” (www.intel.com).www.intel.com

12. 12 Size matters Smallest mass produced transistor 32nm Intel 4004 1971

13. Moore’s Law 13

14. 14 Computing: 60 years ago Wiring ENIAC with a new program

15. 15 Computing: Today Living among computers “Computers” over $50 that serve me

16. 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

17. 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)

18. How about the next 10 years? 18

19. 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. 20 Molecular conformation state Collier et al, 2000

21. More videos about computer history 21 http://www.youtube.com/user/ComputerHistory