【正文】 ........................ 2 基本功能 ................................................................................................................................................................2 擴展功能 ................................................................................................................................................................2 2. 方案論證與比較 ........................................................................................................................ 2 方案一： 采用數字電路 ..................................................................................................................................3 方案二： 采用單片機 .......................................................................................................................................3 方案三：采用 PLC............................................................................................................................................4 方案比較 ................................................................................................................................................................4 設計原理與各部分單元電路的設計 .................................................................................. 5 數字搶答器總體具體方框圖 ........................................................................................................................5 各部分單元電路的設計 ..................................................................................................................................6 完整電路圖設計 .................................................................................................................................................9 4 電路調試 ...................................................................................................................................... 9 搶答器電路 ...........................................................................................................................................................9 秒脈沖發(fā)生電路 ...............................................................................................................................................11 時序控制電路 ................................................................................................................................................... 12 報警電路 ............................................................................................................................................................. 13 整體電路調試 ................................................................................................................................................... 14 5 仿真結果分析 ............................................................................................................................ 15 搶答電路仿真 ................................................................................................................................................... 15 定時電路仿真 ................................................................................................................................................... 15 武漢理工大學《 數字電路 — 多路智能競賽搶答器 》課程設計說明書 總體電路仿真 ................................................................................................................................................... 16 6 心得與體會 ................................................................................................................................ 18 7 參考資料 .................................................................................................................................... 19 8 附錄：電路中的元件介紹 ........................................................................................................ 20 優(yōu)先編碼器 74LS148 ................................................................................................................................... 20 譯碼器 74LS48 ................................................................................................................................................. 21 同步十進制可逆計數器 74LS192............................................................................................................ 23 555 芯片 .............................................................................................................................................................. 25 武漢理工大學《 數字電路 — 多路智能競賽搶答器 》課程設計說明書 武漢理工大學《 數字電路 — 多路智能競賽搶答器 》課程設計說明書 1 摘 要 該搶答器主要是基于 7 4 系列集成芯片組成電路各個部分，成本較低 ，且基本能夠使用于學校的一些活動中。采用 555 定時器和三極管構成報警電路，時序控制電路由 74LS121 產生。s timing of the clock pulse counter circuit to provide. Using 555 timer and alarm circuit transistor constitute, timing control circuit is generated by the 74LS121. SevenSegment LED cathode using a total of digital display and serial number Answer regular time, figures from the 74LS48 decoder digital tube display. In this paper, a digital circuit using a number of significant production Answer multifunctional device, which in addition to the Answer with the basic functions, but also has a regular alarm functions, and several significant features, when the start Answer, the system will automatically countdown, and can be preset time period if it was Answer system will stop the clock, i