外文翻译---带有只读存储器的单片机集成电路-单片机(编辑修改稿)

外文翻译---带有只读存储器的单片机集成电路-单片机(编辑修改稿)内容摘要：

Programmable Read Only Memories. Other new types of device can be erased electrically without the need for ultraviolet light, which are called Electrically Erasable Programmable Read Only Memories, EEPROMs. The microprocessor processes data under the control of the program, controlling the flow of information to and from memory and input/output devices. Some input/output devices are generalpurpose types while others are designed for controlling special hardware such as disc drives or controlling information transmission to other puters. Most types of I/O devices are programmable to some extent, allowing different modes of operation, while some actually contain specialpurpose microprocessors to permit quite plex operations to be carried out without directly involving the main microprocessor. Another major engineering application of microputers is in process control. Here the presence of the microputer is usually more apparent to the user because provision is normally made for programming the microputer for the particular application. In process control applications the benefits lf fitting the entire system on to single chip are usually outweighed by the high design cost involved, because this sort lf equipment is produced in smaller quantities. Moreover, process controllers are usually more plicated so that it is more difficult to make them as single integrated circuits. Two approaches are possible。 the controller can be implemented as a generalpurpose microputer rather like a more robust version lf a hobby puter, or as a „packaged‟ system, signed for replacing controllers based on older technologies such as electromagic relays. In the former case the system would probably be programmed in conventional programming languages such as the ones to9 be introduced later, while in the other case a specialpurpose language might be used, for example one which allowed the function of the controller to be described in terms of relay interconnections, In either case programs can be stored in RAM, which allows them to be altered to suit changes in application, but this makes the overall system vulnerable to loss lf power unless batteries are used to ensure continuity of supply. Alternatively programs can be stored in ROM, in which case they virtually bee part of the electronic „hardware‟ and are often referred to as firmware. To be more precise ,the invention concerns a microcontroller integrated circuit .A microcontroller is usually a VLSI(Very Large Scale Integration) integrated circuit containing all or most of the ponents of a “puter”. Its function is not predefined but depends on the program that it executes. A microcontroller necessarily prises a processor core including a mand sequence (which is a device distributing various control signals to the instructions of a program),an arithmetic and logic unit (for processing the data) and registers(which are specialized memory units). The other ponents of the “puter” can be either internal or external to the microco。