【正文】
反相這將提供每個(gè)指令周期( 微秒)采取的時(shí)間。他本是十二門徒里的每一個(gè)階段是用于振蕩器的特殊 功能的核心 ,如鳳凰社代碼的數(shù)字和樣品中的全部中斷菊花鏈未決的中斷。這些廠家已經(jīng)增加了許多功能及外設(shè),如總線接口 ,模擬到數(shù)字轉(zhuǎn)換器 ,看門狗定時(shí)器、脈沖寬度調(diào)制的輸出。汽車上一般配備 40 多部單片機(jī),復(fù)雜的工 業(yè)控制系統(tǒng)上甚至可能有數(shù)百臺(tái)單片機(jī)在同時(shí)工作!單片機(jī)的數(shù)量不僅遠(yuǎn)超過 PC機(jī)和其他計(jì)算的綜合,甚至比人類的數(shù)量還要多。事實(shí)上單片機(jī)是世界上數(shù)量最多的計(jì)算機(jī)。目前,高端的 32位單片機(jī)主頻已經(jīng)超過 300MHz,性能直追 90 年代中期的專用處理器,而普通的型號(hào)出廠價(jià)格跌落至1 美元,最高端的型號(hào)也只有 10 美元。隨著工業(yè)控制領(lǐng)域要求的提高,開始出現(xiàn)了 16 位單片機(jī),但因?yàn)樾詢r(jià)比不理想并未得到很廣泛的應(yīng)用。 早期的單片機(jī)都是 8位或 4位的。 單片機(jī)也被稱為微控制器( Microcontroller),是因?yàn)樗钤绫挥迷诠I(yè)控制領(lǐng)域。 separate 64K byte address spaces for DATA and CODE memory One 8051 processor cycle consists of twelve oscillator periods. Each of the twelve oscillator periods is used for a special function by the 8051 core such as op code fetches and samples of the interrupt daisy chain for pending interrupts. The time required for any 8051 instruction can be puted by dividing the clock frequency by 12, inverting that result and multiplying it by the number of processor cycles required by the instruction in question. Therefore, if you have a system which is using an clock, you can pute the number of instructions per second by dividing this value by 12. This gives an instruction frequency of 921583 instructions per second. Inverting this will provide the amount of time taken by each instruction cycle ( microseconds). 3 單片機(jī)原理 單片機(jī)是指一個(gè)集成在一塊芯片上的完整計(jì)算機(jī)系統(tǒng)。 two 16 bit timer/counters s largest puter. Modern human life used in almost every piece of electronic and mechanical products will have a singlechip integration. Phone, telephone, calculator