24秒倒計(jì)時(shí)設(shè)計(jì)

1、籃球 24 秒倒計(jì)時(shí)器的設(shè)計(jì)李娟 ）指導(dǎo)教師:宋衛(wèi)星計(jì)時(shí)器；數(shù)碼顯示器；MultisimThe design of basketball 24 seconds countdownLi Juan ） This design aims at completing a twenty-four seconds times of basketball competition,shows thefunctions of counting down twenty-four seconds and the settings of external switch,controls the timers func

2、tionof clear,start,pause or continue.When cleared directly,The digital display shows nothing but zero.The twenty-fourtimer counts decending with interval of one second. Besides,if the twenty-four timer decreases to zero,the light ofthe digital display is still on and gives out alarm signal at the sa

3、me time.Timer;Digital display; Multisim目錄引言 .11、設(shè)計(jì)思路，基本原理和框圖 .11.1設(shè)計(jì)思路 .11.2基本原理 .11.3 總體設(shè)計(jì)框圖.22、芯片簡(jiǎn)介 .22.1 74LS48 .22.2 555定時(shí)器 .22.3 74LS192.23、單元模塊 .33.1信號(hào)發(fā)生部分 .33.2倒計(jì)時(shí)部分 .43.3停止控制電路 .43.4警報(bào)提示裝置 .54、總設(shè)計(jì)（總電路圖） .錯(cuò)誤！未定義書簽。5、安裝、調(diào)試步驟 .錯(cuò)誤！未定義書簽。6、總結(jié) .錯(cuò)誤！未定義書簽。7、心得體會(huì) .錯(cuò)誤！未定義書簽。參考文獻(xiàn) .7附錄 .7 3 / 十位顯示譯碼驅(qū)動(dòng)個(gè)位

4、顯示譯碼驅(qū)動(dòng)計(jì)數(shù)器圖 1.3.1 總體設(shè)計(jì)框圖0g共7 3 LT Dg7 D圖 2.2.1 555芯片引腳+-:當(dāng)端當(dāng) .圖2.3.1 74LS192引腳圖,0,即。與 。由C和TCT和 ABCDEFG74LS48NVCC5VDADNVCC5VB C D CG01 41 1 9 1 1 5 4 8VCCRSTOUTDISTHRTRIR5300110kERz1.01.0F圖 3.1.2 信號(hào)發(fā)生部分 VCC5VCKU2U4CKU31312111091514OAOBOCODOEOFOG1312111091514OAOBOCODOEOFOGA B C D E F GLTRBIBI/RBOA B C

5、D E F GLTRBIBI/RBO74LS48NR71kCC6V1CDCAVDAS4S1鍵= AVCC5V501 1 1 9 1 1 5 4 8G501 1 1 9 1 1 5 4 8鍵= B鍵= CLD 的 對(duì) 。1.數(shù)字電路技術(shù)基礎(chǔ)簡(jiǎn)明教程(第三版)M.北京:高等教育出版社,2006:165-166,396-415.2.電子技術(shù)基礎(chǔ) 數(shù)字部分（第五版）M.北京：高等教育出版社，2006.1.3陳大欽，電子技術(shù)基礎(chǔ)實(shí)驗(yàn) M.北京：高等教育出版社， 2000年.9.可預(yù)置時(shí)間的倒計(jì)時(shí)電路J.電子世界，1995，(11).1個(gè)2 個(gè)2 個(gè)1 個(gè)1 個(gè)1 個(gè)1 個(gè)電容1.0uF74LS19274LS00U4U1CKU371261312111091514ABCDOA71261312111091514ABCDOAOBOCODOEOBOCODOE354LT OFRBI OGBI/RBO354LT OFRBI OGBI/RBO74LS48N74LS48N1k3 2 6S4 S5S