Alan M Turing 1912 1954 n n n

Alan M. Turing (1912 – 1954) n n n led the WWII research group that broke the code for the Enigma machine proposed a simple abstract universal machine model for defining computability devised the “Turing hypothesis” for AI

Turing and Colossus n constructed an electronic computing machine (1943) used to decrypt German coded messages

Maurice Wilkes (1913 - ) n n n his Cambridge group constructed EDSAC in 1949 the first stored program, general-purpose electronic digital computer first to use symbolic programs (assembly)

UNIVAC-1 n n first commercial generalpurpose computer system successor to Mauchly. Eckert BINAC delivered in 1951 used to forecast the 1952 presidential election

Computing Generations n FIRST GENERATION (1950 s) vacuum tube technology n SECOND GENERATION (early 1960 s) solid-state technology, magnetic core memories n THIRD GENERATION (1964 – 1970) integrated circuitry (SSI), dynamic memories n LATER GENERATIONS (1970 s – ) VLSI, microprocessors, ultra large-scale integration

IBM/360 n n n built using solid-state circuitry family of computer systems with backward compatibility established the standard for mainframes for decades

DEC PDP Series n n n “minicomputers” offered mainframe performance at a fraction of the cost introduced the unibus architecture for CPU interconnections

Supercomputers n n n high-performance systems used for scientific applications advanced designs (pipelining, parallelism, etc. ) Control Data Corporation, Cray Research, and others

Desktop Computers n n n microprocessors all-in-one designs, performance/price tradeoffs aimed at mass audiences personal computers workstations

Comparison Shopping How do they rate in cost and performance?

Moore’s Law n n n increased density of components on chip Gordon Moore: “Number of transistors on a chip will double every year. ” since 1970’s development has slowed a little n Number of transistors doubles every 18 months cost of a chip has remained almost unchanged higher packing density means shorter electrical paths, giving higher performance trends: smaller size, reduced power and cooling requirements, fewer interconnections

DRAM and Processor Characteristics

Improving Memory Performance n n n increase the number of bits per word, width of data paths employ cache structures to reduce the frequency of memory operations increase the bandwidth of interconnections

Pentium Evolution (1) n n 8080 n first general purpose microprocessor n 8 bit data path 8086, 88 n 16 bit n instruction cache, prefetch few instructions n 8088 (8 bit external bus) used in first IBM PC 80286 n 16 Mbyte memory addressable 80386 n 32 bit n Support for multitasking

Pentium Evolution (2) n n n 80486 n sophisticated cache and instruction pipelining n built in math co-processor Pentium n superscalar, multiple instructions executed in parallel Pentium Pro n increased superscalar organization n branch prediction n data flow analysis n speculative execution

Pentium Evolution (3) n n Pentium II n MMX technology n graphics, video & audio processing Pentium III n additional floating point instructions for 3 D graphics Pentium 4 n more floating point and multimedia enhancements Itanium n 64 bit