COMPUTER AS IT IS

Date: 2015-10-07; view: 751.

Working in pairs make up dialogues discussing the following problems. You are a computer novice.

1. Ask another student to describe the computer. Touch upon these aspects hardware and software CPU, main memory, peripherals.

2. Discuss main types of computers giving both their advantages and disadvantages.

SUPPLEMENTARY READING

Any computer is, architecturally, like any other

computer in the early days of computers.

However, there are differences. They are the following: an early processor used to be made of thousands of vacuum tubes. Reliability was measured in mere hours between failures, and the cooling plant was often larger than the computer itself. Then the transistor was invented. The number of them was enormous in each mainframe. Besides, in computers of the 1950's, the transistors, diodes, resistors, capacitors and other components were mounted on printed-circuit (PC) cards. A typical 5-in. card contained a dozen transistors and a hundred other parts. A card might have contained a single flip-flop and a thousands cards were required to build each computer.

In the early 1960's semiconductors makers created a wholly new technology: a whole flip-flop could be integrated. Several of integrated circuits (ICs) could be mounted on a single printed card. Soon, improved fabrication processors enabled even more complex circuit to be created in a single IC. The new technology was called medium-scale integration (MSI), and the older technology was labeled small-scale integration (SSI). The progress towards smaller computers continued.

If used for computers discrete transistors were too costly and unreliable, they were too large and too slow.

In the 1960's advances in microelectronic components led to the development of the minicomputer, followed more recently by an even smaller microcomputer. Both have filled a need for small relatively flexible processing systems able to execute comparatively simple computing functions at lower cost.

In 1971, Intel Corp. delivered the first microprocessor, the 4004. All the logic to implement the CPU, the central processing unit, of a tiny computer was put onto a silicon chip less than 1/4-in square. That design was soon followed by many others. The progress towards smaller computers is likely to continue: there is already talk of nano-computers pico-computers. When the central processing unit (CPU) of a computer is implemented in a single or very small number of integrated circuits, we call it a microprocessor. When a computer incorporates a microprocessor as its major component, the resulting configuration is called a microcomputer. When the entire computer, including CPU, memory and input-output capability, is incorporated into a single IC, we also call that configuration a microcomputer. To distinguish between the two microprocessor types, we call the latter a one-chip microcomputer.

Modern computer and microelectronic devices have interacted so closely in their evolution that they can be regarded as virtually symbiotic. Microelectronics and data processing are linked.