Computer Organisation, Generations & Current Trend

1. Computer Organisation,Generations & Current Trend Prof. Sujata Rao Session 2

2. The C P U Control Unit Main Memory Input Arithmetic&Logic Unit Output Auxiliary & Backup Store Store Storage Device Retrive Display Display Output Keyboard Central Processing Unit ( C P U )

3. Main Memory Supervisory Memory Read Only Memory (R O M ) Control Unit BIOS Main Memory Appln Prgm Exec Prgm O/S User memory Arithmetic&Logic Unit Random Access Memory ( R A M ) for Read & Write

4. R O M 1. Masked ROM 2. P R O M 3. E P R O M 4. E E P R O M (R O M ) BIOS Supervisory Memory Control Unit Main Memory Appln Prgm Exec Prgm O/S Random Access Memory ( R A M ) for Read & Write User memory Arithmetic&Logic Unit D A T A

5. 4 Type of R O M • Masked R O M – • A bit pattern is permanently recorded. • Specialised Manufacturing Process. • Very Expensive • P R O M - Programmable Read Only Memory • Can be programmed by User • Using PROM Prgm can burn the fuses according to the bit pattern - “Burning the PROM” • E P R O M – Erasable Programmable Read Only Memory. • Info stored is Semi-Permanent. • Can be erased by exposing the memory to Ultra Violet Rays. • Can be programmed again • Most commonly used

6. E E P R O M – Electricity Erasable - Programmable Read Only Memory • Similar to EPROM • Info can be altered using electrical signals • Manufacturing process is quite complex • Not commonly Used • Very Expensive E A P R O M - Electricity Alterable - Programmable Read Only Memory

7. Types of Computer Analog Digital Hybrid • Analog - Solves Problem by operating on contineous Variables. • Digital - performs arithmetic, logical & comparative functions on info in digital form • Combines features of Analog & Digital

8. Types Of Hardware & Software Prof. Sujata Rao Session 2

9. Abacus

11. Generation of Computers • 1st - Tubes & Vales, large in size, Slow operating Speed, Limited Programming Capacity, Short Life Span, Generated lot heat • 2nd - Transistors , smaller in size, faster speed, lesser in cost & High reliability • 3rd - Semiconductors, CHIP made of IC’s in mid 60’s, increased ALU capability, ability to perform parallel operation, improvement of instructions, much smaller , reduction in cost drastically • 4th - silicon chips, high resolution monitors, graphics improved,speed improved, size & cost reduced.

12. Super Grids • Made by universities and the military (Virginia Tech with 1100 Apple G5 dual processors, for example) and other clusters of less powerful machines with Linux special OSs for parallel processing.

13. Types of Computer • Grid Computer • Super Computer • Mainframes • Mini Computer • Microcomputer • Terminal Embedded Computer

14. Super Grids • Made by universities and the military (Virginia Tech with 1100 Apple G5 dual processors, for example) and other clusters of less powerful machines with Linux special OSs for parallel processing.

15. Super Computer CDC 6600 designed by Seymour Cray (First commercially successful supercomputer-speed of 9 megaflops)

16. Supercomputers Cray Research-CRAY I vector architecture (designed by Seymour Cray, shaped the computer industry for years to come), Cray 1 - 1976 (courtesy Cray Inc.)

17. Thinking Machines, The Connection Machine, as this model is called, contains 64,000 CPUs

18. Players in the supercomputing arena • In 40 years (2004) there are but a few players left in the supercomputing arena: • Cray • Dell • HP (absorbed: Amdahl, Compaq who ate Digital) • IBM • NEC • SGI • Sun

19. Companies • IBM 3090 VPF.Evans • Sutherland ES-1, • Fujitsu VP-400E, • NSFnet established Apollo, Ardent, and Stellar Graphics Supercomputers, • Hitachi S-820/80, Hypercube simulation on a LAN at ORNL,CRAY Y-MP, • Tim Berners-Lee: World Wide Web project at CERN • Seymour Cray: Founds Cray Computer Corp.-Begins CRAY 3 using gallium arsenide chips • Bell Labs - Optical Processors • Intell - Paralell Processors

20. Mainframes Eniac (1946) Mark I mainframe (1950's) BINAC(1960's)

21. Mainframe Mainframe is an industry term for a large computer. The name comes from the way the machine is build up: all units (processing, communication etc.) were hung into a frame. Thus the main computer is build into a frame, therefore: Mainframe

22. Manufacturers • Amdahl, • Burroughs, • CDC • Cray, • Fujitsu, • Hitachi, • Hewlett Packard, • IBM, • Intel, • NEC, • SGI, • Sun, • Texas Instruments, • Thinking Machines • Univac

23. Charecteristics • A mainframe has 1 to 16 CPU's (modern machines more) • Memory ranges from 128 Mb over 8 Gigabyte on line RAM • Its processing power ranges from 80 over 550 Mips • It has often different cabinets for • Storage • I/O • RAM

24. Separate processes (program) for • task management • program management • job management • serialization • catalogs • inter address space • communication

25. Characteristics • centralized computing opposite from distributed computing. Meaning all computing takes (physically) place on the mainframe itself: the processor section . • main purpose is to run commercial applications of Fortune 1000 businesses and other large-scale computing purposes.

26. IBM 4381 mainframe processor from 1985

27. The First Generation, 1951-1956 • Marked the beginning of commercial computing. • High-speed Vacuum Tube • Computers operated withoutoperating system. • Operators who would select the job to be run, initially load the system program, run the user’s program, and then select another job, and so forth.

28. Programs were written in high level, procedure-oriented languages. • Application programs were run one at a time, • Translators with absolute computer addresses. • Executable program were made by combining object program along with any existing library programs. • There was no provision for moving a program to different location in storage for any reason.

29. Development of programming languages was moving away from the basic machine languages; • 1st assembly language, and • 2nd procedure oriented languages, COBOL • The most significant being the development of FORTRAN & PASCAL.

30. The second Generation, 1956-1964 • 2nd Gen computer hardware were made of Transistors which replaced the vacuum tubes. • Important changes in hardware and software architectures occurred during this period. • The computer systems were Punch Card and Tape-oriented Systems. • Random access devices like Disks came to use towards the end of the second generation. • Program processing was done by large centralized computers operated under mono programmed batch processing operating systems.

31. Programs were executed by processing the Machine Instructions in a strictly sequential order. • CPU (high speed electronic component ) • I/O operations which involved mechanical devices (card readers and tape drives) that were slower. • The second generation was a period of intense operating system development. • Researchers began to experiment with multi-programming and multiprocessing.

32. The Third Generation, 1964-1979 • Officially began in 1964 with IBM’s announcement of its System/360 family of computers. • Hardware technology began to use integrated circuits (ICs) • Yielded significant advantages in both speed and economy. • Operating system were development which handled multiprogramming. • These O/S could handle I/O buffering in the form of spooling operating systems.

33. These systems reader could move input jobs from cards to disk, • System writer to move job output from disk to printer, tape, or cards. • The spooling operating system in fact had multiprogramming since more than one program was resident in main storage at the same time. • Users shared not only the system’ hardware but also its software resources and file system disk space.

34. The third generation developed both computer hardware and the accompanying operating system. • During this period, the topic of operating systems became, in reality, a major element of the discipline of computing.

35. The minicomputers of the third generation. • Examples are Microsoft’s DOS for IBM-compatible personal computers and UNIX for workstation. • However, many of these desktop computers are now connected as networked or distributed systems.

36. The Fourth Generation, 1979 - Present • 4th generation had electronic circuits which replaced the ICs ex. the PC & the workstation • The component technology of the 3rd generation, was replaced by very large scale integration (VLSI), in the fourth generation. • The inexpensive workstation-class computer capable of supporting multiprogramming and time-sharing. • O/s supports personal computers and workstations too.

38. End Lesson 2

39. The fourth generation had electronic circuits which replaced the ICs seen in the personal computer and the workstation. The component technology of the third generation, was replaced by very large scale integration (VLSI), in the fourth generation. • We now have the inexpensive workstation-class computer capable of supporting multiprogramming and time-sharing. Hence the operating systems that supports today’s personal computers and workstations look much like those which were available for the minicomputers of the third generation. Examples are Microsoft’s DOS for IBM-compatible personal computers and UNIX for workstation. • However, many of these desktop computers are now connected as networked or distributed systems.