【正文】 the dc + 5 V. This design limited the number of eight, vies to answer first vies to answer first process is as follows: when the host to press the start button vies to answer first, digital display shows vies to answer first time countdown, and in the last five second start alarm circuit hint, in vies to answer first time eight players in the process vies to answer first, after the success display module, vies to answer first demonstrated contestant number and answer the question time. To answer the question, can press the stop button host, a new round of vies to answer first began to end. If the host did not press the start button and contestant vies to answer first vies to answer first, it shall be regarded as the foul, display module shows FF and demonstrated contestant number, and alarm circuit hints. According to stop button host, a new round of vies to answer first began after. Display module in the initial display, exceed the prescribed vies to answer first time still no contest and the answer in excess of the prescribed time shows FFF. Vies to answer first time and answer problem of time can set, set a range of 199 s, original state vies to answer first time for 10 s and answer the question time for 30 s. Backstage host can vies to answer first time to adjust key, answer time to adjust key and time add 1 , minus 1 button modify vies to answer first time and player answer problem of time after time, change stop button certain that the new time to start the effective. In the design process, vies to answer first do first overall scheme, and then analyses the argument for the working principle of the system, and based on this, the design of unit of the circuit principle diagram, further to the design of the system to plete the circuit. In the working principle of the system based on the study of the fully, and choose appropriate ponent model and parameter, garnish with protel drawing software draw circuit principle diagram, according to write software interface circuit program. Keyword: vies to answer first。 S11 and S12 respectively for time add 1 and minus 1 button。 during the countdown, the host would like to stop the countdown,can press the stop button, the system will automatically enter the state.The system USES the software and hardware of the method of bining and design, including hardware design are borrowed from the singlechip microputer AT89C51 as the center control module, the modular design division, with six module, respectively is: the core control module, the power modules, clock and reset module, key input module, display module, alarm module. The software design is the mon assembly language programming. Key input module in 14 key, divided into vies to answer first keys and control buttons. Vies to answer first key there were eight, respectively, for vies to answer first S8 S1players use vies to answer first。 contestants in the set period of time vies to answer first, viesl to answer first effectively, on the monitor demonstrated contestant39。 vies to answer first instruments have lock to save and displayl function. That39。 when the host to start start button, the timer vies to answerl first to reduces the time, vies to answer first time after running prohibit contest。 host can through the intelligence is set button vies to answer first each question time and answer the vies to answer first time。關(guān)鍵字：搶答器；單片機(jī)；AT89C51；模塊；按鍵IntroductionThe intelligent vies to answer first as a kind of electronic products have been widely applied in all kinds of intelligence and knowledge petition situation. But using the current is some plicated circuit vies to answer first, do not facilitate production, and reliability, low difficult to achieve。在搶答器設(shè)計過程中，首先完成總體方案的論證制定，然后分析系統(tǒng)的工作原理，在此基礎(chǔ)上設(shè)計出各部分單元電路原理圖，進(jìn)一步完成對系統(tǒng)電路的設(shè)計。搶答時間和回答問題的時間可以設(shè)定，設(shè)定范圍為199s，原始狀態(tài)下?lián)尨饡r間為10s，回答問題時間為30s。主持人按“停止按鍵”后，新一輪搶答開始。回答完問題后，主持人可按“停止按鍵”結(jié)束，新一輪搶答開始。電源模塊是為了增強(qiáng)本系統(tǒng)應(yīng)用的廣泛性而設(shè)計的模塊，它的主要任務(wù)是將交流220V電壓轉(zhuǎn)換為系統(tǒng)中可以直接使用的穩(wěn)定的直流+5V。時鐘與復(fù)位模塊包括時鐘電路和復(fù)位電路，單片機(jī)的時鐘信號用來提供單片機(jī)片內(nèi)各種操作的時間基準(zhǔn)，復(fù)位操作則使單片機(jī)的片內(nèi)電路初始化，使單片機(jī)從一種確定的初態(tài)開始運(yùn)行。搶答按鍵共有八個，分別為S1―S8，供搶答選手進(jìn)行搶答使用；控制按鍵有六個，分別為S9―S14， 其中S9和S10分別為“搶答時間調(diào)整鍵”和“回答時間調(diào)整鍵”；S11和S12分別為時間“加1”和“減1”按鍵；S13和S14分別為“搶答開始按鍵”和“停止按鍵”。軟件設(shè)計是采用匯編語言編程。即選手按下按鍵，鎖存相應(yīng)選手的參賽編號，并在LED數(shù)碼管上顯示，選手搶答實(shí)行優(yōu)先鎖存，其他按鍵者將不能響應(yīng)，以便公平地選擇第一個搶答者；參賽選手在設(shè)定的時間內(nèi)進(jìn)行搶答，搶答有效，顯示器上顯示選手的編號，同時進(jìn)入回答問題的時間倒計時；倒計時期間，主持人想終止倒計時，可以按下“停止”鍵，系統(tǒng)會自動進(jìn)入準(zhǔn)備狀態(tài)。根據(jù)搶答器的功能，智能搶答器的設(shè)計要求如下：搶答器可以同時供8名選手或8個代表隊比賽使用；主持人可以通過智能搶答器的按鍵設(shè)定每道題的搶答時間和回答時間。為適應(yīng)多選手搶答活動的需要而設(shè)計一個智能搶答器，這種搶答器具有電路簡單，元件普通，易于購買等優(yōu)點(diǎn)，很好地解決了制作者制作困難和難于購買的問題。設(shè)計總說明智能搶答器作為一種電子產(chǎn)品已廣泛應(yīng)用于各種智力和知識競賽場合。但目前所使用的搶答器有的電路較復(fù)雜，不便于制作，而且可靠性低，實(shí)現(xiàn)起來很困難；有的則用一些專用的集成芯片，而專用集成芯片的購買又很困難。本系統(tǒng)就是采用AT89C51單片機(jī)為核心而設(shè)計的八路智能搶答器。具有清零和非法搶答控制功能，設(shè)置一個系統(tǒng)清除和搶答控制開關(guān)，并由主持人操控；當(dāng)主持人啟動“開始搶答按鍵”后，定時器進(jìn)行減計時，搶答時間耗盡后禁止搶答；倒計時5秒時，如果仍無人搶答，則系統(tǒng)每1s報警一次，用以提示參賽選手；搶答器具有鎖存與顯示功能。本系統(tǒng)采用軟硬件結(jié)合的方法而設(shè)計，其中硬件設(shè)計是借用單片機(jī)AT89C51為中心控制模塊，采用模塊化設(shè)計思想，根據(jù)系統(tǒng)功能劃分成六個模塊，分別為：核心控制模塊、電源模塊、時鐘與復(fù)位模塊、按鍵輸入模塊、顯示模塊、報警模塊。按鍵輸入模塊共有14個按鍵，分為搶答按鍵和控制按鍵。顯示模塊本系統(tǒng)采用四個共陽極LED數(shù)碼管顯示，一個數(shù)碼管用來顯示搶答到問題的選手的號碼，兩個用來顯示倒計時時間，一個未使用的數(shù)碼管作為以后的擴(kuò)展使用。報警模塊在本系統(tǒng)中為附加模塊，它的主要用途就是起到提示并引起人們的注意。本設(shè)計限定搶答人數(shù)為八人，搶答過程如下：當(dāng)主持人按“搶答開始按鍵”后，數(shù)碼顯示屏顯示搶答時間倒計時，并在最后五秒啟動報警電路提示，在搶答時間過程中八名選手進(jìn)行搶答，搶答成功后，顯示模塊顯示選手號和回答問題時間。如果在主持人沒有按下“搶答開始按鍵”而選手就搶答，則視為犯規(guī)，顯示模塊顯示“FF”并顯示選手號碼，而且報警電路進(jìn)行提示。顯示模塊在初始顯示、超過規(guī)定搶答時間仍無人搶答和答題超過規(guī)定時間后顯示“FFF”。后臺主持人可以通過“搶答時間調(diào)整鍵”、“回答時間調(diào)整鍵”和時間“加1”、“減1”按鍵修改搶答時間和選手回答問題的時間時間，改完后“停止按鍵”確定，新時間開始有效。在對系統(tǒng)工作原理充分研究的基礎(chǔ)上，選擇合適的元件型號和參數(shù)，再用protel繪圖軟件畫出電路原理圖，最后根據(jù)電路接口編寫軟件程序。 Others use some special integrated chips, and the purchase of the special integrated chips and very difficult. In order to adapt to the needs of the many players vies to answer first activities and design a intelligent vies to answer first device, this vies to answer first instruments have circuit is simple, ponents, easy to buy ordinary etc, and solves the difficult and hard to buy makers make the problem. This system is AT89C51 microcontroller as the core and the design of the intelligent vies to answer first 8. According to the function, intelligent vies to answer first the vies to answer first the desig