CS 146The Big Picture in Computer Science Prof. Daniel Ernst February 28th, 2011 Computer Hardware
What would you say is the greatest invention of the 20th century? (ABC News poll, 1999) Top responses% Computers 30 Automobile 12 Electricity 9 Television 9 Telephone/Telecommunications 7 Airplane 4 Medicines/Vaccinations 4 “The transistor; without it, the XBOX would probably be the size of a city.” - nate66, some xbox forum ???
Introduction of Microelectronics Miniaturization of immense proportions Transistor: This is an abbreviated combination of the words "transconductance" or "transfer", and "varistor". The device logically belongs in the varistor family, and has the transconductance or transfer impedance of a device having gain, so that this combination is descriptive. — Bell Telephone Laboratories — Technical Memorandum (May 28, 1948) Integrated Circuit: Miniaturized electronic circuit manufactured in a thin layer of semiconductor material.
The Power of Miniaturization EDSAC 1 (1949) ~ 500 OPs Pentium 4 (2002) ~ 12 GFLOPs 24,000,000 times faster
A picture is worth 1000 words… (or a billion transistors)
Managing Complexity with Abstraction • Designers deal with the extreme complexity of microprocessors by using abstraction. • Focus only on 1-2 levels of abstraction at a time • Similar to OOD • Don’t need to know how the module works, just that it does work. • And the interface
Levels of Abstraction in a Computer System Apps Applications – Generic Software Operating System – Controlling Software O/S hardware Architecture – HW/SW Interface Arch software marchitecture – High-level organization mArch Logic Digital Logic – Building-block Modules Digital Digital Circuits – Continuous Discrete Analog Circuits – Fun with Electricity Analog Devices – Transistors, Capacitors, etc. Devices Physics Physical Properties – Electrons, Ions, etc.