基于單片機AT89C51的數(shù)字搶答器設計

摘    要：搶答器作為一種電子產(chǎn)品已廣泛應用于各種智力和知識競賽場合。一個八路數(shù)字搶答器的設計需要考慮到可更改回答及搶答時間功能，利用AT89C51單片機及外圍接口實現(xiàn)的搶答系統(tǒng)，利用單片機的定時器/計數(shù)器定時和記數(shù)的原理，將軟硬件有機地結(jié)合起來，使得系統(tǒng)能夠正確地進行計時，同時使數(shù)碼管能夠正確地顯示時間。用開關做鍵盤輸出，揚聲器發(fā)聲提示。同時系統(tǒng)能夠?qū)崿F(xiàn)在搶答中只有開始后搶答才有效，如果在開始搶答前搶答為無效；搶答限定時間和回答問題的時間可在1-99s設定，可以顯示是哪位選手有效搶答和無效搶答，正確按鍵后有音樂提示，搶答時間和回答問題時間倒記時顯示，滿時后系統(tǒng)計時自動復位及主控強制復位，按鍵鎖定，在有效狀態(tài)下，按鍵無效非法。
基于單片機AT89C51的數(shù)字搶答器設計， 首先完成總體方案的論證制定，繪制控制臺的總體框圖，然后分析系統(tǒng)的工作原理，在此基礎上設計出各部分單元電路原理圖，分析其工作原理，進一步完成對系統(tǒng)電路的設計。在對系統(tǒng)工作原理充分研究的基礎上，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。

關鍵詞：AT89C51； LED數(shù)碼管； 搶答器； 計時器

Eight-way first answer device based on AT89C51
Abstract: Responder as an electronic products have been widely used in intelligence and knowledge competitions occasions. An eight-way digital answering device designed to take into account to answer and answer in time to change the function, using AT89C51 microcontroller and external interface of the answer system, using single chip timer / counter the principle of timing and counting, will organically combine hardware and software , allows the system to correctly time, while the digital control to correctly display the time. Switching to do with the keyboard output, speaker voice prompts. At the same time the system can be achieved only after the beginning of the Responder Responder only effective if started before the Responder Responder to be invalid; answer in a limited time and the time to answer questions can be set in 1-99s, which players can display is effective and ineffective Responder Responder , the correct button prompt after the music, answer in time and answer the questions of time countdown display, the system time after the expiration of the master force automatic reset and reset, the keys are locked in an effective state, the button is not illegal.
AT89C51 microcontroller based digital answering device design, the first complete demonstration of the overall program development, rendering the overall block diagram of the console, and then analyze the working principle, based on the design of this unit of each part of the circuit schematic, and its working principle, further complete the system circuit design. The system works in full on the basis, select the appropriate component models and parameters, and then draw protel schematic drawing software. 
Key words: AT89C51; LED digital tubes; the first answer device; Time

目    錄
1. 概    述 1
1.1 課題的相關背景 1
1.2 選題的目的和意義 1
1.3 課題研究的內(nèi)容 1
1.4 課題的優(yōu)點及組成 1
2. 方案論證 2
3. 搶答器的系統(tǒng)概述 3
3.1 國內(nèi)外的研究現(xiàn)狀 3
3.2 搶答器的簡介 3
3.3 系統(tǒng)需求分析 4
3.4 搶答器運行的流程圖 4
3.5 搶答器的工作過程 6
3.6 AT89C51的功能及簡介 6
3.7 AT89C51特殊功能寄存器 9
4. 硬件設計模塊 10
4.1 硬件電路的設計 10
4.2 穩(wěn)壓電源電路設計 11
4.3 時鐘頻率電路的設計 12
4.4 復位電路的設計 12
4.5 顯示電路的設計 13
4.6 鍵盤掃描電路的設計 14
4.7 發(fā)聲電路的設計 16
4.8 系統(tǒng)復位 16
5. 軟件設計模塊 19
5.1 主程序系統(tǒng)結(jié)構(gòu)圖 19
5.2 軟件任務分析 19
5.3 程序流程圖 20
5.4 Proteus軟件仿真系列組圖 21
6. 結(jié)束語 23
參考文獻 24
致    謝 25