Lecture-03 PC History

Evolution of Computer s Mechanical Calculators Mechanical Computers Electronic Computers –Tubes –Transistors –ICs

Highlights

“Napiers Bones” for calculating 1617 “Napiers Bones” was the starting point that lead to the search for a better way to achieve mathematical calculations. –John Napier created “Napiers Bones” for calculating. –Similar to abacus.

digital adding machine 1642 –Blaise Pascal introduced Pascaline digital adding machine. –First adding machine. –Could add numbers entered on dials.

calculator capable multiplying 1671 –Gottfried Wilhelm von Leibniz invented a calculator capable of adding and multiplying. –It was built in 1694.

first successful mechanical calculator 1820 –Charles Xavier Thomas developed first successful mechanical calculator that was capable of adding, subtracting, multiplying and dividing. Calculator

Mechanical Computers 1822 –Charles Babbage (father of computers) invents the Difference Engine. Solved polynomial equations. Steam-powered and capable of printing results Father of computers

program-controlled, mechanical computer 1833 –Charles Babbage designed a general- purpose, program-controlled, automatic mechanical computer.

Never built –Called the Analytical Engine. –Capable of working on 50 digit numbers with a storage capacity of 1, digit numbers. –Input would have been accomplished through punch cards. –Considered first true general purpose computer. –Would have included: Input deviceControl unit ProcessorStorage Output device –Never built because intricate gear and mechanisms could not be built.

Punch cards & IBM 1890 –Punch cards developed by Herman Hollerith for input and storage. –Herman later founded Tabulating Machine Company, also known as IBM.

vacuum tube 1906 Deforest invents a vacuum tube that later serves as one of the first types of electronic switches in a computer circuit.

binary numbers 1937 Iowa State College professor invents the base-two (binary) numbers instead of the traditional base ten. Bits - Short for “Binary Digits”

First electronic digital computer 1942 –First digital computer created by a physicist, John V. Atanasoff using vacuum tubes (patented in 1906) as switches.

Stored-program technique 1945 –John Von Neumann demonstrated that computers did not needed to be rewired to enter a new program. –Stored-program technique became fundamental for future generations of high- speed digital computers.

Transistorised Computers 1947 –First transistors developed. –The invention of the transistor that lead revolution to the miniaturization of circuitry. –EDVAC and UNIVAC computers appeared. They did not need to be rewired for new programs. Used RAM.

First large scale electronic computer 1946 –First large scale electronic computer built for the military. –ENIAC, Electrical Numerical Integrator and Calculator Operated on 10 digit numbers, could multiply two such numbers 300 times a second by finding the value of the product from a multiplication table stored in memory. Used 18,000 tubes, needed 1,800 square feet of space, consumed 180,000 watts of power. Punch cards used for input and output. Registers used for adders and quick-access storage. Programs were entered into ENIAC by rewiring it.

Integrated circuit Computers 1959 –Integrated circuit developed. –Texas Instruments invented the IC (Integrated Circuit) –Third generation computers were born.

First microprocessor –First microprocessor. –4-bit Intel 4004 –Smaller than a thumbnail, with 2300 transistors on board. –As powerful as the first electronic computer, ENIAC and cost $200.

First personal computer 1975 –First personal computer sold, Altair. –Used CP/M (Control Program for Microprocessors) and BASIC language.

Computers Kit 1975 MITS introduced the “Altair” featuring an 8080 processor and 256 Bytes of memory for $395.

First Personal Computers 1975 IBM introduced the”Model 5100” with 16 Kilobytes of memory for $9,000.

Apple Computers 1976 Apple introduced the “Apple I” for $666. In the 1980’s, Apple was the primary dominating force behind PCs.

IBM started developing personal computers End of 1980 –IBM started developing personal computers. –Contracted out operating system and software development to a small company, Microsoft.

The IBM Personal Computer Wednesday, August 12th, 1981, IBM changed the face of computing by releasing the “IBM PC” Digital Research was originally contacted to write the OS (Operating System) but balked. A small, fledgling company named Microsoft eagerly took up the task

What is a PC? “IBM Compatible” or “Clone” Who controls Hardware and Software? Microsoft was free to sell their OS (DOS) to anyone, making IBM clones seemingly identical to their competition

IBM compatibles Now –IBM compatibles made and improved by hundreds of companies. –Apple Macintosh is a closed system and they control the primary system software.

What is a PC? Intel is the leader in PC processors Intel develops chipsets to support their processors Intel develops new expansion buses such as PCI and AGP Intel makes motherboards for leading vendors such as Dell and Gateway

System Types 8 Bit 16 Bit 32 Bit 64 Bit PC/XT systems AT systems ATX systems

System Types PC - Personal Computer XT systems - Extended Systems (PC + HD) AT systems - Advanced Technology 16 bits Shape, layout, Power supply brought different Form Factors: PC/XT, AT, AT/Desk, AT/Tower, Baby-AT, LPX, ATX, NLX, SFX, ATX Auxiliary, ATX12V, ATX Optional, Dell Proprietary ATX

Moore’s Law Each new chip contains roughly twice as much capacity as its predecessor, and each new chip is released with months. Computing power is rising exponentially over a brief period of time.