Реферат: Development Of Computers And Technology Essay Research

have a very basic, fixed physical construction, and yet be able to carry out any

kind of computation by means of a proper programmed control without the need for

any change in the unit itself. Von Neumann contributed a new consciousness of

how sensible, yet fast computers should be organized and assembled. These ideas,

usually referred to as the stored-program technique, became important for future

generations of high-speed digital computers and were wholly adopted. The Stored-

Program technique involves many features of computer design and function besides

the one that it is named after. In combination, these features make very high

speed operations attainable. An impression may be provided by considering what

1,000 operations per second means. If each instruction in a job program were

used once in concurrent order, no human programmer could induce enough

instruction to keep the computer busy. Arrangements must be made, consequently,

for parts of the job program (called subroutines) to be used repeatedly in a

manner that depends on the way the computation goes. Also, it would clearly be

helpful if instructions could be changed if needed during a computation to make

them behave differently. Von Neumann met these two requirements by making a

special type of machine instruction, called a Conditional control transfer –

which allowed the program sequence to be stopped and started again at any point

- and by storing all instruction programs together with data in the same memory

unit, so that, when needed, instructions could be changed in the same way as

data.

As a result of these techniques, computing and programming became much

faster, more flexible, and more efficient with work. Regularly used subroutines

did not have to be reprogrammed for each new program, but could be kept in

“libraries” and read into memory only when needed. Hence, much of a given

program could be created from the subroutine library. The computer memory

became the collection site in which all parts of a long computation were kept,

worked on piece by piece, and put together to form the final results. When the

advantage of these techniques became clear, they became a standard practice. The