plc外文翻譯

1、<p><b>　　畢業(yè)設(shè)計外文翻譯</b></p><p>　　Under a lot of circumstances we are total to like to adopt the string to combine the conversion chip to carry on deliver, under this kind of circumstance not n

2、eed us to carry on to deposited the machine to establish too and complicatedly, but carry on the data exchanges through the data transmission instruction directly, but is not a very viable way in the correspondence, beca

3、use the PLC of the other party must has been wait for your data exportation at the time of sending out the data, it can't</p><p>　　When you are reading the book, you hear someone knock on door, you stop

4、to start up of affair, open the door and combine to continue with the one who knock on door a dialogue, the telephone of this time rang, you signal hint to connect a telephone, after connecting the telephone through, ret

5、urn overdo come together knock on door to have a conversation, after dialogue complete, you continue again to see your book, this kind of circumstance we are called the interruption to it, it has the authorit</p>

6、<p>　　The interruption is not only a, sometimes existing jointly with the hour several inside break, break off to have the preferred Class, they will carry out the interruption of the higher Class according to perso

7、n's request. This kind of breaks off the medium interruption to also became to break off the set. The Class that certainly break off is relevant according to various resources of CPU with internal PLC, also following

8、 a heap of capacity size of also relevant fasten.</p><p>　　The contents that break off has a lot of kinds, for example the exterior break off, correspondence in of send out and accept the interruption and se

9、ttle and the clock that count break off, still have the WDT to reset the interruption etc., they enriched the CPU to respond to the category while handle various business. Speak thus perhaps you can't comprehend the

10、internal structure and operation orders of the interruption completely also, we do a very small example to explain.</p><p>　　Each equipment always will not forget a button, it also is at we meet the urgent c

11、ircumstance use of, which is nasty to stop the button. When we meet the Human body trouble and surprised circumstances we as long as press it, the machine stops all operations immediately, and wait for processing the ove

12、r surprised empress recover the operation again. Nasty stop the internal I/ O of the internal CPU of the button conjunction PLC to connect up, be to press button an exterior to trigger signal for CP</p><p>　

13、　When we are work a work piece, giving the PLC a signal, counting PLC inner part the machine add 1 to compute us for a day of workload, a count the machine and can solve problem in brief, certainly they also can keep the

14、 data under the condition of dropping the electricity, urging the data not to throw to lose, this is also what we hope earnestly.</p><p>　　The PLC still has the function that the high class counts the machin

15、e, being us while accept some dates of high speed, the high speed that here say is the data of the in all aspects tiny second class, for example the bar code scanner is scanning the data continuously, calculating high-sp

16、eed signal of the data processor DSP etc., we will adopt the high class to count the machine to help we carry on count. It at the PLC carries out the procedure once discover that the high class counts the machine</p&g

17、t;<p>　　You heard too many this phrases perhaps:" crash", the meaning that is mostly is a workload of CPU to lead greatly, the internal resources shortage etc. the circumstance can't result in proced

18、ure circulate. The PLC also has the similar circumstance, there is a watchdog WDT in the inner part of PLC, we can establish time that a procedure of WDT circulate, being to appear the procedure to jump to turn the mista

19、ke in the procedure movement process or the procedure is busy, movement time of the proce</p><p>　　The PLC development has already entered for network ages of correspondence from the mode of the one, and tog

20、ether other works control the net plank and I/ O card planks to carry on the share easily. A state software can pass all se hardwires link, more animation picture of keep the view to carries on the control, and cans pass

21、 the Internet to carry on the control in the foreign land, the blast-off that is like the absolute being boat No.5 is to adopt this kind of way to make airship go up the sk</p><p>　　The development of the hi

22、gher layer needs our continuous effort to obtain. The PLC emergence has already affected a few persons fully, we also obtained more knowledge and precepts from the top one experience of the generation, coming to the cont

23、inuous development PLC technique, push it toward higher wave tide.</p><p>　　Knowing the available PLC network options and their best applications will ensure an efficient and flexible control system design.&

24、lt;/p><p>　　The programmable logic controller's (PLC's) ability to support a range of communication methods makes it an ideal control and data acquisition device for a wide variety of industrial automat

25、ion and facility control applications. However, there is some confusion because so many possibilities exist. To help eliminate this confusion, let's list what communications are available and when they would be best

26、applied.</p><p>　　To understand the PLC's communications versatility, let's first define the terms used in describing the various systems.</p><p>　　ASCII: This stands for "American

27、Standard Code for Information Interchange." As shown in Fig. 1, when the letter "A" is transmitted, for instance, it's automatically coded as "65" by the sending equipment. The receiving equi

28、pment translates the "65" back to the letter "A." Thus, different devices can communicate with each other as long as both use ASCII code.</p><p>　　ASCII module: This intelligent PLC modul

29、e is used for connecting PLCs to other devices also capable of communicating using ASCII code as a vehicle.</p><p>　　Bus topology: This is a linear local area network (LAN) arrangement, as shown in Fig. 2A,

30、in which individual nodes are tapped into a main communications cable at a single point and broadcast messages. These messages travel in both directions on the bus from the point of connection until they are dissipated b

31、y terminators at each end of the bus.</p><p><b>　　畢業(yè)設(shè)計外文翻譯</b></p><p>　　很多的情況下我們總喜歡采用串并轉(zhuǎn)換芯片來進行傳輸，這種情況下不需要我們進行過于復(fù)雜的寄存器設(shè)置了，而直接通過數(shù)據(jù)傳送指令進行數(shù)據(jù)交流，但在通信中并不是一個十分可行的辦法，因為在發(fā)送數(shù)據(jù)的時候?qū)Ψ降腜LC必須一直等待你的數(shù)

32、據(jù)輸出，它不能去做其他的工作。</p><p>　　當你在看書的時候，你聽到有人敲門、你停下手上的事情、去打開門、并同敲門者對話、這個時候電話響了、你示意接個電話、在接完電話后、回過頭來同敲門者繼續(xù)對話、對話完畢后、你再繼續(xù)看你的書，這種情況我們把它稱為中斷，它具有權(quán)威性，也具有優(yōu)先性，PLC具備了這樣的功能。它的特點在于我們在設(shè)備的操作過程中可能會遇到緊急的突發(fā)事件，我們要立刻的停下手上的工作，去處理更重要的事

33、情，這種情況是我們經(jīng)常所遇到的，PLC在去執(zhí)行緊急的任務(wù)時，總會先保存目前的狀態(tài)，比如程序的地址，CPU的累加器數(shù)據(jù)等，就像我們?nèi)ラ_門時要記下我們看的書在第幾頁了或者干脆作個記號，因為我們待會還要繼續(xù)接著看后面的書。CPU總是按照我們的意愿去做應(yīng)該做的事情，但你錯誤的給它一件事情，它也會同樣的去做，這一點我們必須注意。</p><p>　　中斷并不是只有一個，有時會同時存在幾個中斷，中斷具有優(yōu)先的級別，他們會根據(jù)

34、人的要求去執(zhí)行更高級別的中斷。這種中斷中的中斷也就形成了中斷嵌套。當然中斷的級別根據(jù)各種PLC內(nèi)部CPU的資源有關(guān)，同時也跟堆棧的容量大小也有關(guān)系。</p><p>　　中斷的內(nèi)容有很多種，比如外部中斷、通信中的發(fā)送和接受中斷、定時和計數(shù)的時鐘中斷、還有WDT復(fù)位中斷等，它們豐富了CPU在處理各種事務(wù)時響應(yīng)種類。這樣講也許你并不能完全理解中斷的內(nèi)部結(jié)構(gòu)和操作順序，我們做一個小小的例子來說明.</p>

35、<p>　　每一個設(shè)備總是不會忘記有一個按鈕，它也是在我們遇到緊急情況時使用的，那就是急停按鈕。當我們遇到人身事故和意外情況時我們只要按下它，機器立即停止所有的操作，并等待處理完意外后再恢復(fù)操作。急停按鈕連接PLC內(nèi)部CPU的內(nèi)部I/O接口上，當按鈕給CPU一個外部觸發(fā)信號時，CPU對I/O進行再次檢測，當確認有外部觸發(fā)信號時，CPU保護現(xiàn)場并將程序計數(shù)器自動轉(zhuǎn)到相應(yīng)的外部I/O中斷程序中去，當外部中斷程序處理完畢，程序計數(shù)

36、器返回到主程序繼續(xù)工作。有一點可以說明的是我們一般會把急停按鈕的外部中斷升至最高級別，從而保證安全。</p><p>　　當我們在工作完一個工件時，給PLC一個信號，將PLC的內(nèi)部計數(shù)器加1來計算我們一天的工作量時，一個簡單的計數(shù)器能解決問題，當然它們也能夠在掉電的情況下保持數(shù)據(jù)，促使數(shù)據(jù)不丟失，這也是我們所渴望的。</p><p>　　PLC還具有高級計數(shù)器的功能，當我們在接受一些高速的

37、數(shù)據(jù)時，這里所說的高速是在在微秒級的數(shù)據(jù)，比如條碼掃描機在不斷的掃描數(shù)據(jù)，數(shù)據(jù)處理器DSP計算的高速信號等，我們就要采用到高級計數(shù)器來幫助我們進行計數(shù)。它在PLC執(zhí)行程序時一旦發(fā)現(xiàn)高級計數(shù)器對應(yīng)的中斷，就會立即放下手上的工作。經(jīng)過再次編程的梯形圖程序說明我們在執(zhí)行程序時高級計數(shù)器會自動的執(zhí)行對應(yīng)的工作，從而將高級計數(shù)器的級別升至高一級別。</p><p>　　你也許聽過太多的這個詞:“死機”，大致的意思是CPU工

38、作量過大，內(nèi)部資源不足等情況造成程序無法運行。PLC也有類似的情況，在PLC內(nèi)部有一個看門狗WDT，我們可以設(shè)置WDT一個程序運行的時間，當程序運行過程中出現(xiàn)程序跳轉(zhuǎn)錯誤時或者程序繁忙時，程序的運行時間超過WDT的設(shè)置時間，CPU轉(zhuǎn)而WDT復(fù)位狀態(tài)。程序重新開始運行，但對中斷不會進行破壞。</p><p>　　PLC的發(fā)展已經(jīng)從單一的模式進入了通信的網(wǎng)絡(luò)時代，并同其它的工控網(wǎng)板和I/O卡板輕易的進行共享。組態(tài)軟件

39、可以將所有的這些硬件連接起來，通過更直觀的動畫圖片來進行控制，并可以通過互聯(lián)網(wǎng)在異地進行控制，像神舟五號的發(fā)射就是采用這種辦法來使飛船升空。</p><p>　　更高層次的發(fā)展需要我們不斷的努力來取得。PLC的出現(xiàn)已經(jīng)足足影響了幾代人，我們也從上一輩的經(jīng)驗中獲取了更多的知識和教訓(xùn)，來不斷的發(fā)展PLC技術(shù)，將它推向更高浪潮。</p><p>　　了解可用的PLC網(wǎng)絡(luò)的最佳選擇，其應(yīng)用將確保有

40、效率和靈活的控制系統(tǒng)設(shè)計?？删幊踢壿嬁刂破鳎≒LC的）能夠支持多種通信方法的范圍，使之成為一個理想的控制和工業(yè)自動化和控制應(yīng)用各種設(shè)施數(shù)據(jù)采集裝置。然而，有一些混亂，因為這么多的可能性存在。為了幫助消除這種混亂，讓我們的通訊名單，可什么時候他們會是最好的應(yīng)用。</p><p>　　CPU：這代表“中央處理單元”，這其實就是一臺計算機，可編程控制器，智能設(shè)備或其他地方的算術(shù)和邏輯運算的執(zhí)行和指令被解碼和執(zhí)行的一部分

41、。</p><p>　　菊花鏈：這是對單個設(shè)備中的PLC網(wǎng)絡(luò)，連接描述在那里，每個設(shè)備連接到下一個和通信信號從一個單位傳遞到下一個順序的方式。</p><p>　　分布式控制：這是一個自動化的概念，即一個自動化系統(tǒng)的部分是由單獨的控制器，這是在位于其附近地區(qū)的直接控制（控制分散控制系統(tǒng)及遍布出）。</p><p>　　為了了解PLC的通信多功能性，讓我們首先定義描述

42、的各種制度的用語：</p><p>　　ASCII碼：這代表著信息交換。1，當字母“A”是傳播，例如，它會自動編碼為“65由發(fā)送設(shè)備”。接收設(shè)備轉(zhuǎn)換的“65”回答。因此，不同的設(shè)備可以相互通信既是使用ASCII代碼的其他長。</p><p>　　ASCII的模塊：這個智能PLC模塊是用于連接到PLC的通信也使用ASCII碼作為車輛等設(shè)備的能力。</p><p>