COMPUTER ARCHITECTURE

Computer Architecture



Computer Architecture

The size of ENIAC's numerical 'word' was 10 decimal digits, and it could reproduce two of these figures at a rate of 300 per second, by finding the value of each product from a Multiplication table stored in its memory. ENIAC was about 1000 times faster than the preceding generation of computers. ENIAC used 18,000 vacuum tubes, about 1,800 square feet of floor space, and consumed about 180,000 watts of electric power. It had punched business business card input, 1 multiplier, 1 divider/square rooter, and 20 adders utilising decimal ring counters, which assisted as adders and furthermore as quick-access (.0002 seconds) read-write list storage. The executable instructions making up a program were embodied in the separate flats' of ENIAC, which were closed simultaneously to pattern a 'route' for the flow of inpatternation. The difficulty with the ENIAC was that the mean life of a vacuum tube is 3000 hours, and a vacuum tube would then burn out one time every 15 minutes. It would take on mean 15 minutes to find the scorched out tube and restore it (Clint, 2000).

Enthralled by the achievement of ENIAC, the mathematician John Von Neumann undertook, in 1945, a study of computation that showed that a computer should have a very rudimentary, repaired physical building, and yet be adept to convey out any kind of computation by means of a correct programmed command without the need for any change in the unit itself. Von Neumann assisted a new consciousness of how shrewd, yet fast computers should be coordinated and assembled. These concepts, generally mentioned to as the stored-program technique, became significant for future generations of high-speed digital computers and were wholly adopted. The Stored-Program method engages many features of computer design and function besides the one that it is entitled after. In combination, these characteristics make very high hasten procedures attainable. An effect may be provided by considering what 1,000 operations per second means. If each direction in a job program were utilised once in concurrent order, no human programmer could induce sufficient instruction to hold the computer busy. Arrangements must be made, consequently, for components of the job program (called subroutines) to be used frequently in a manner that depends on the way the computation goes. Also, it would apparently be cooperative if directions could be changed if required throughout a computation to make them behave differently. Von Neumann contacted these two requirements by making a special type of appliance instruction, called a Conditional command move -- which permitted the program sequence to be halted and started afresh at any issue - and by saving all instruction programs together with data in the identical recollection unit, so that, when required, directions could be changed in the same way as data (Clint, 2000).

Early in the 50's two significant technology discoveries changed the likeness of the electronic-computer area, from one of very quick but unreliable hardware to an image of relatively high reliability and even more ...