外文翻译--工程中的微型计算机.docVIP

英文翻译资料 Systems Using Microprocessors Electronic systems are used for handling information in the most general sense; this information may be telephone conversation, instrument reading or a companys accounts, but in each case the same main types of operation are involved: the processing, storage and transmission of information. In conventional electronic design these operations are combined at the function level: for example a counter, whether electronic or mechanical, stores the current count and increments it by one as required. A system such as an electronic clock which employs counters has its storage and processing capabilities spread throughout the system because each counter is able to store and Process numbers. Present day microprocessor based systems depart from this conventional approach by separating the three functions of processing , storage , and transmission into different section of the system .This partitioning into three main functions was devised by Von Neumann during the 1940s, and was not conceived especially for microcomputers. Almost every computer ever made has been designed with this structure, and despite the enormous range in their Physical forms, they have all been of essentially the same basic design. In a microprocerror based system the Processing will be performed in the microprocessor so itself. The storage will be by means of memory circuits and the communication of information into and out of the system will be by means of special input/output (I/O) circuits. It would be impossible to identify a particular piece of hardware which performed the counting in a microprocessor based clock because the time would be stored in the memory and incremented at regular intervals by the microprocessor. However , the software which defined the systems behavior would contain sections that performed as counters．The apparently rather abstract approach to the architecture of the microprocessor and its associated circuits allows it to be very flexible i