個人計算機相關(guān)知識-預覽頁
【正文】 re, however, ti will continue to be necessary to interconnect a number of integrated circuits to make a microputer whenever larger amounts of storage or input/output are required. 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 the benefits of fitting the entire system on to a single chip are usually outweighed by the high design cost involved, because this sort of 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. In the former case the system would be programmed in conventional programming language such as the ones to 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 to be altered to suit changes in application , but this makes the overall system vulnerable to loss of 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. More sophisticated process controllers require miniputers for their implementation , although the use of large scale integrated circuits “blurs”the distinction between mini and microputers .products and process controllers of various kinds represent the majority of presentday microputer applications, the exact figures depending on one’s interpretation of the word ‘product’.virtually all engineering and scientific uses of microputers can be assigned to one or these categories. 個人計算機什么是個人計算機按照容量大小，有許多類型的的計算機，例如巨型計算機，大型計算機，小型計算機和個人計算機。它們常常會用在中型企業(yè)的內(nèi)部的部門，例如政府部門中。便攜計算機（便攜機）計算機技術(shù)的另一重要發(fā)展是便攜機以被大量使用。所以他給了用戶相當大的方便。便攜機使用又薄又輕的顯示屏，稱為平板顯示器或LCD監(jiān)視器。便攜機是字自足型機器，有自己的CPU、存儲器和磁盤驅(qū)動器，而且許多便攜機帶有調(diào)制解調(diào)器和CDROM. 便攜機雖然比具有同等計算能力的臺式計算機要貴些，但對走出辦公室或旅行中需要第二臺計算機的移動用戶是理想的。這些計算機重量超過 25磅，并且不能方便地帶到稍遠的距離。諸如采用計數(shù)器的電子鐘之類的任一系統(tǒng)要使存儲和處理能力遍布整個系統(tǒng)，因為每個計數(shù)器都能存儲和處理一些數(shù)字。從此幾乎所有制成的計算機都是用這種結(jié)構(gòu)設計的，盡管包含寬廣的物理形式，從根本上來說它們均是具有相同的基本設計。但是，規(guī)定系統(tǒng)運轉(zhuǎn)過程的軟件包含實現(xiàn)記數(shù)功能的單元。該系統(tǒng)由微處理器控制，它管理自己與存儲器和輸入/輸出單元的信息傳輸。微計算機常使用的RAM（隨機存儲器），在RAM中的數(shù)據(jù)可被寫入，并且在需要時可被再次讀出。有些ROM在制造時將其數(shù)據(jù)標本放入，而另外的則可通過特殊的設備由用戶編程，所以稱為可編程ROM。大多數(shù)類型的I/O裝置在某種程度下可編程，允許不同形式的操作，而有些則包含特殊用途微處理器的I/O裝置不用主微處理器的直接干預，就可以實施非常復雜的操作。當技術(shù)進一步發(fā)展，更強更強的處理器和更大更大數(shù)量的存儲器被包含形成單片微型計算機，結(jié)果使最終產(chǎn)品的裝配成本得以節(jié)省。在過程控制應用中，由于這種設備以較少的數(shù)量生產(chǎn)，將整個系統(tǒng)安裝在單個芯片上所獲得利益常比不上所設計的高設計成本。兩種情況下，程序均能存于RAM，這讓程序能按應用情況變化時進行相應的變化，但是這使得系統(tǒng)易受掉電影響而工作不正常，除非使用電池保持供電連續(xù)性。
法律信息相關(guān)推薦
鄂ICP備17016276號-1