TEXT A. MICROCOMPUTER AND MICROPROCESSOR DESIGN

1. Since the transistor was invented, no single electronics innovation has had such an impact as microcomputer. Powered by tiny semiconductor chips containing computing elements with the same power and functions previously found only in large scale computers, these microcomputers systems are now being applied to literally thousands of applications. Microcomputers are automating assembly lines, providing the heart of sophisticated electronic games, making “intelligent” computer peripherals even faster. This revolution in occurring because microcomputers are very inexpensive, easy to implement into a system, and significantly reduce the time and cost of product development.

2. The microcomputers were the fist computers to use a single microprocessor chip as the processor. Personal computers and small business computers are microcomputers. 8-bit microprocessors usually support only one user terminal and have a maximum of 64 KB of memory. 16-bit microcomputers may support several user terminals and usually have a maximum of 1 million bytes of memory. As the power of microcomputers increase, they can be used in two ways. They can be used either as a central computer (providing processing for several user terminals), or as a more powerful single computer for an individual user (see figure 2).

3. A microprocessor is the tiny processor used, as mentioned above, in microcomputers. The microprocessor requires a power supply and memory to be a complete computer. Microprocessors are also used in minicomputers, mainframes and peripheral devices, as well as in all industrial and consumer products which use a computer.

4. As usual processors all microprocessors have the ability to fetch (obtain from memory) and execute a limited set of instructions, to perform addition and subtraction on a binary word, and to input (take in) and output (put out) binary data. After fetching an operational code from the program in memory, while this operation is being executed, the program counter is automatically incremented by one unit. At the completion of the instruction, it is then ready with the address for the following program instruction. In many situations the microprocessors have many more capabilities that application requires.

5. In conclusion some words more about single-chip microcomputers. They, where control functions and memory circuits reside on one chip, are beginning to appear in consumer appliances. One of their attractions is the fact that programmable read-only memories (PROMs) that can be included on these chips require no electrical power to retain data. In addition to providing permanent storage, PROMs also allow one type of micro to be stocked as a standard component that can be programmed individually to provide a variety of control functions.

6. Just as computer circuits have grown smaller, so too have memory circuits. Moreover, new technologies such as the bubble memory and Josephson-junction memory show the ability for providing more compact memories that retain data with little or no applied power. These new memories allow micros to be used where power Is not always available and conventional read-only memories do not have enough capacity.

Figure 2. Block Diagram of a Typical Microcomputer with a Microprocessor

Notes

innovation - новшество

an impact – зд. влияние

Powered by tiny semiconductor chips – Приводимые в действие крошечными полупроводниковыми кристаллами (чипами)

literally - буквально

”intelligent” – “умный” (зд, применительно к вычислительной машине)

product development - зд. выпуск продукции

in conclusion – в заключение

micro = microcomputer – микрокомпьютер

Josephson-junction memory – запоминающее устройство с переходом Джозефсона (прогрессивная технология изготовления полупроводниковых кристаллов (чипов)пересечением слоев сверхпроводящих металлов)