【正文】 出，然后調(diào)用顯示子程序顯示當(dāng)前的輸出情況，由于定時(shí)器中中斷入口 打開鎖存器，送段選信號，然后關(guān)閉 打開鎖存器送位選信號，然后關(guān)閉 定時(shí)器重轉(zhuǎn)初值 位選標(biāo)志位左移一 位 返回 河南城建學(xué)院本科畢業(yè)設(shè) 計(jì)論文 電路軟件設(shè)計(jì) 20 斷程序 執(zhí)行一次只能顯示一位數(shù)據(jù)，所以要設(shè)定 一個(gè)全局變量的顯示緩沖區(qū)和全局變量的位選標(biāo)志。這樣可以降低一些硬件設(shè)計(jì)的難度，初次設(shè)計(jì)應(yīng)切合自己的水平。 uchar code tosin[256]={0x80,0x83,0x86,0x89,0x8d,0x90,0x93,0x96,0x99,0x9c,0x9f,0xa2,0xa5,0xa8,0xab,0xae,0xb1,0xb4,0xb7,0xba,0xbc,0xbf,0xc2,0xc5 ,0xc7,0xca,0xcc,0xcf,0xd1,0xd4,0xd6,0xd8,0xda,0xdd,0xdf,0xe1,0xe3,0xe5,0xe7,0xe9,0xea,0xec,0xee,0xef,0xf1,0xf2,0xf4,0xf5 ,0xf6,0xf7,0xf8,0xf9,0xfa,0xfb,0xfc,0xfd,0xfd,0xfe,0xff,0xff,0xff,0xff,0xff,0xff,0xff,0xff,0xff,0xff,0xff,0xff,0xfe,0xfd ,0xfd,0xfc,0xfb,0xfa,0xf9,0xf8,0xf7,0xf6,0xf5,0xf4,0xf2,0xf1,0xef,0xee,0xec,0xea,0xe9,0xe7,0xe5,0xe3,0xe1,0xde,0xdd,0xda ,0xd8,0xd6,0xd4,0xd1,0xcf,0xcc,0xca,0xc7,0xc5,0xc2,0xbf,0xbc,0xba,0xb7,0xb4,0xb1,0xae,0xab,0xa8,0xa5,0xa2,0x9f,0x9c,0x99 河南城建學(xué)院本科畢業(yè)設(shè)計(jì)論文 附錄 A：系統(tǒng)程序 25 ,0x96,0x93,0x90,0x8d,0x89,0x86,0x83,0x80,0x80,0x7c,0x79,0x76,0x72,0x6f,0x6c,0x69,0x66,0x63,0x60,0x5d,0x5a,0x57,0x55,0x51 ,0x4e,0x4c,0x48,0x45,0x43,0x40,0x3d,0x3a,0x38,0x35,0x33,0x30,0x2e,0x2b,0x29,0x27,0x25,0x22,0x20,0x1e,0x1c,0x1a,0x18,0x16 ,0x15,0x13,0x11,0x10,0x0e,0x0d,0x0b,0x0a,0x09,0x08,0x07,0x06,0x05,0x04,0x03,0x02,0x02,0x01,0x00,0x00,0x00,0x00,0x00,0x00 ,0x00,0x00,0x00,0x00,0x00,0x00,0x01,0x02 ,0x02,0x03,0x04,0x05,0x06,0x07,0x08,0x09,0x0a,0x0b,0x0d,0x0e,0x10,0x11,0x13,0x15 ,0x16,0x18,0x1a,0x1c,0x1e,0x20,0x22,0x25,0x27,0x29,0x2b,0x2e,0x30,0x33,0x35,0x38,0x3a,0x3d,0x40,0x43,0x45,0x48,0x4c,0x4e ,0x51,0x55,0x57,0x5a,0x5d,0x60,0x63,0x66 ,0x69,0x6c,0x6f,0x72,0x76,0x79,0x7c,0x80 }。z3。 } void keyscan()//按鍵掃描程序 { uchar temp。 } while(temp!0xf8)//松手檢測 { P2=0xf8。 EA=1。 TH0=(655365000)/256。t charge you more than 35% of your pensation if you win the case. If you are thinking about signing up for a damagesbased agreement, you should make sure you39。t really grow up, it seems is not so important?？傆X得自己自己似乎應(yīng)該去做點(diǎn)什么，或者寫點(diǎn)什么。 } TR1=1。 DAC0832(temp)。 TH1=(655365000)/256。 case 0xb8:key4()。 } } void key4()//頻率 +位操作 { if(chuzhi==3900) chuzhi=3900。 } void key2()//幅值 +位操作 { uchar z。//定義模式位和幅值位 uint chuzhi。 通過兩個(gè)月的畢業(yè)設(shè)計(jì)，進(jìn)一步的加深了我對專業(yè)課的理解和認(rèn)識，畢業(yè)設(shè)計(jì)是我在大學(xué)四年的最后一堂課，也是對我大學(xué)四年所學(xué)的知識的一個(gè)最好的評估。 /ASE：自動(dòng)存儲(chǔ)使此控制端接 Vl時(shí)， AUTOSTORE 被使能，接 VDD 時(shí)被禁止，用戶可動(dòng)過將其置低電平，存儲(chǔ)當(dāng)前的電阻值，在下次復(fù)位的時(shí) 候直接使用當(dāng)前河南城建學(xué)院本科畢業(yè)設(shè)計(jì)論文 各部分功能模塊 17 的阻值。 河南城建學(xué)院本科畢業(yè)設(shè)計(jì)論文 各部分功能模塊 14 V R E F8R F B9GND10I O U T 111I O U T 212D I 713D I 614D I 515D I 416D I 07CS1W R 12GND3D I 34D I 25D I 16X F E R17W R 218I L E19VDD20D A C 0 8 3 2814321L M 3 5 8 D814321L M 3 5 8 DR2R1R3OUTV R E F 圖 如圖為常用的雙極性轉(zhuǎn)化電路，第一個(gè)運(yùn)算放大器將電流信號轉(zhuǎn)變?yōu)殡妷盒盘?，第二個(gè)運(yùn)算放大器和電阻 R1,R2共同組成方向加法器，由于電流輸出接的是第一個(gè)運(yùn)算放大器的反相輸出端，所以當(dāng)滿足 2*R2=R1且 R2=R3的時(shí)候輸出電壓為 Vout=Vi（ Vref/2） 當(dāng)要實(shí)現(xiàn)雙極性輸出的時(shí)候幅值的二進(jìn)制碼要轉(zhuǎn)為偏移二進(jìn)制碼，即 將二進(jìn)制碼對應(yīng)的零值偏移到 80H，在偏移之后，只有幅值二進(jìn)制碼大于 128 的輸出才為正，后則為負(fù)。 P 1P 2P 3P 4P 5P 6P 7P 8R S T9P 10P 11P 12P 13P 14P 15P 16P 17X T A L 218X T A L 119V S S20P 21P 22P 23P 24P 25P 26P 27P 28P S E N29A L E / P R O G30E A / V P P31P 32P 33P 34P 35P 36P 37P 38P 39V C C40 A T 89C 51V C C 圖 專用的鍵盤電路能夠?qū)崿F(xiàn)鍵盤的輸入，而且讀取數(shù)據(jù)也比較簡單，例如周立功公司的數(shù)碼管鍵盤擴(kuò)展電路 7289，能同時(shí)控制 8位 7段共陰極數(shù)碼管和 64個(gè)按鍵輸入，內(nèi)部自帶消抖設(shè)置，當(dāng)檢測按鍵輸入時(shí)能夠給單片機(jī)發(fā)送中斷信號，并直接將對應(yīng)的值發(fā)送給單片機(jī)，而不需要單片機(jī)另外程序?qū)ζ溥M(jìn)行識別，數(shù)碼管顯示部分能夠通過單片機(jī)設(shè)置各位的顯示段碼，并設(shè)置其導(dǎo)通與否和偏移方向。與微處理器完全兼容。 模塊的結(jié)構(gòu)劃分 圖 本次我選用的是單片機(jī)通過查表獲得某一時(shí)刻對用的波形幅值，經(jīng)過 DAC轉(zhuǎn)化器，轉(zhuǎn)化為對應(yīng)的模擬信號，幅值的調(diào)節(jié)主要是通過調(diào)節(jié) DAC的基準(zhǔn)電壓實(shí)現(xiàn)，頻率的調(diào)節(jié)則是 單 片 機(jī) 顯示 鍵盤 D/A 轉(zhuǎn)換 雙極性轉(zhuǎn)化電路 河南城建學(xué)院本科畢業(yè)設(shè)計(jì)論文 各部分功能模塊 5 第三章 各部分功能模塊 單片機(jī)模塊 本次設(shè)計(jì)選用的單片機(jī)芯片是 AT89C51 單片機(jī)。 實(shí)現(xiàn) 多功能信號發(fā)生器波形 種類、 波形的頻率、幅值 的狀態(tài)及數(shù)據(jù)的顯示 。 關(guān)鍵詞： 信號發(fā)生器 單片機(jī) 波形調(diào)整 II Abstract Signalgenerator is a kind of signal source in mon use, broadly applied at the electronics electric circuit, auto control system and teaching experiment etc. Currently used mostly function signal generator signal generator, waveform generator and a special price of expensive . So the dissertation is usage of the AT89s51 singlechip microputer constitute of waveform generator, which can generate triangle wave, square wave, sine wave etc variety waveform, the period of wave can be controlled by procedure, at outer circle spare part of the machine, plus independence type keyboard , which can control wave increase or decrease of formfrequency and the choice of waveform, at the same time LED display frequency size. The output of the machine connect DAC0832 to carry on a DA conversion， again pass operation amplifier to put an end exportation waveform. This design has advantage of simple circuit, tightly packed structure, cheap price, superior function etc. Based on the introduction of MAX038 , we discussed the principle and the whole frame of the digital function signal generator. We described the control of the oscillatory frequent , amplitude and the digital display in detail. Thegenerator can output three kinds of waves : sine wave , square wave , triangle wave. Keywords： signal generator MCU waveform adjustment 河南城建學(xué)院本科畢業(yè)設(shè)計(jì)論文 目錄 III 目 錄 1．緒論 ：課程背景目的及意義???????????????????? 1 ：設(shè)計(jì)任務(wù)和要求?????????????????????? 2 2．方案的研究 ：方案的提出和整論????????????????????? 3 ：模塊的結(jié)構(gòu)劃分?????????????????????? 4 3．各部分功能模塊 ：單片機(jī)模塊???????????????????????? 5 ：電源模塊???? ???????????????