2023電子競賽簡易頻率測試儀

簡易頻率特性測試儀〔E題〕摘要：該簡易頻率特性測試儀采用STM32F103ZET6核心板，主要由自制正交掃描信號源、RLC被測網(wǎng)絡(luò)、乘法器、低通濾波等功能模塊組成；測試數(shù)據(jù)包含信號的幅頻特性及相頻特性，于彩屏TFT上顯示。本系統(tǒng)利用高速DDS〔AD9854〕模塊實(shí)現(xiàn)信號發(fā)生電路，能輸出雙端口的正交信號，并可控制設(shè)置其幅值與頻率。被測網(wǎng)絡(luò)采用RLC串聯(lián)諧振電路，到達(dá)要求的網(wǎng)絡(luò)通帶中心頻率。將DDS產(chǎn)生的正交信號和被測網(wǎng)絡(luò)信號通過乘法器AD835模塊，經(jīng)LTC1564低通濾波，利用單片機(jī)上的片上AD進(jìn)行采樣，最終在彩屏上顯示輸出，完成對信號的幅頻和相頻的簡單測試。關(guān)鍵詞：STM32；DDS；乘法器；濾波；TFTAbstract:Thesimplefrequencytesterisbasedonhigh-performanceSTM32F103ZET6controller,anditmainlyconsistsofself-maidsignalgenerator,RLCnetwork,multipliers,low-passfilterandotherfunctionblocks.Thetestdatacontainsamplitude-frequencycharacteristicsandphase-frequencycharacteristics,andwillbedisplayedonTFT.Thesystemuseshigh-speedDDS(AD9854)blockassignalcircuit,generatingthedual-portquadraturesignals,whoseamplitudeandfrequencycanbecontrolledandset.ThetestnetworkismadeofRLCcircuit,whichisabletoachievethestandardizedcenterfrequency.ThequadraturesignalsgeneratedbyDDSandthesignalsundertestpassthroughthemultiplierAD835andtheLTC1564low-passfilter,andwillbesampledbythe12-biton-chipADC.ThefinaloutputisdisplayedontheTFTtocompletethetestofamplitude-frequencyandphase-frequency.Keyword:STM32;DDS;multiplier;filter;TFT一、方案選擇與論證·······································31.1正交掃頻信號源的設(shè)計(jì)與選擇·································31.2乘法器模塊的設(shè)計(jì)與選擇·····································31.3低通濾波器的設(shè)計(jì)與選擇·····································31.4ADC模塊的設(shè)計(jì)與選擇·······································31.5被測網(wǎng)絡(luò)的設(shè)計(jì)與選擇·······································4二、電路設(shè)計(jì)·············································42.1正交掃描信號源設(shè)計(jì)電路·····································42.2模擬乘法器設(shè)計(jì)電路·········································42.3低通濾波器設(shè)計(jì)電路·········································42.4末級電壓抬升設(shè)計(jì)電路·······································5三、系統(tǒng)設(shè)計(jì)·············································53.1方案總體設(shè)計(jì)描述···········································53.2理論分析與計(jì)算·············································63.2.1正交掃描信號發(fā)生器的設(shè)計(jì)·······························63.2.2低通濾波器的設(shè)計(jì)·······································63.2.3RLC被測網(wǎng)絡(luò)的設(shè)計(jì)·····································63.2.4特性曲線顯示···········································7四、軟件設(shè)計(jì)·············································7五、系統(tǒng)測試·············································85.1測試方法··················································85.2測試工具··················································85.3各模塊測試過程············································85.3.1掃頻信號發(fā)生器的測試··································85.3.2乘法器模塊的測試······································95.3.3輸入輸出阻抗的測試····································95.3.4RLC被測網(wǎng)絡(luò)的測試····································9六、結(jié)論················································10參考文獻(xiàn)·················································10附錄·····················································10附錄一：元件清單··················································10附錄二：AD9854掃描信號發(fā)生器設(shè)計(jì)電路······························11附錄三：系統(tǒng)總體設(shè)計(jì)電路···········································11附錄四：主要程序清單···············································12方案選擇與論證1.1正交掃頻信號源的設(shè)計(jì)與選擇方案一：采用程控鎖相環(huán)頻率合成方案。方案說明：鎖相環(huán)頻率合成是將高穩(wěn)定度和高精度的標(biāo)準(zhǔn)頻率經(jīng)過算術(shù)運(yùn)算產(chǎn)生同樣穩(wěn)定度和精確度的大量離散頻率，在一定程度上解決了既要頻率穩(wěn)定精確，又要頻率在較大范圍內(nèi)可變的問題。但該方案采用屢次積分電路，這種具有惰性特性的電路誤差大，不能滿足幅頻曲線和相頻曲線的輸出要求。方案二：采用AD9854芯片搭建DDS模塊電路，通過控制AD9854存放器可產(chǎn)生編程控制的、高精度的頻率信號。方案說明：AD9854是AD公司生產(chǎn)的DDS專用芯片，其擁有300MHz的內(nèi)部時(shí)鐘頻率，可以進(jìn)行FSK、BPSK、PSK、chirp、AM等的操作。AD9854數(shù)字合成器是一個(gè)利用DDS技術(shù)、兩個(gè)內(nèi)部高速高性能正交DACs控制數(shù)字可編程輸入輸出的綜合器件。當(dāng)給AD9854加上一個(gè)確定時(shí)鐘時(shí)，它可以生成高度穩(wěn)定、頻率-相位-幅度可編程的正弦信號，頻率分辨率很高、抗干擾能力強(qiáng)、靈敏度高、實(shí)用性強(qiáng)。綜上論證比較，我們選用方案二作為正交掃頻信號源的實(shí)現(xiàn)方式。1.2乘法器模塊的設(shè)計(jì)與選擇方案一：采用晶體管等分立元件搭建差分對模擬乘法器電路，通過兩個(gè)晶體管輸出的電壓乘積項(xiàng)到達(dá)頻率變換作用。方案說明：電路結(jié)構(gòu)冗繁復(fù)雜，穩(wěn)定性差，不易調(diào)節(jié)。方案二：直接采用模擬乘法器AD835芯片。方案說明：AD835是一款電壓輸出型四象限模擬乘法器，帶寬高達(dá)250MHz，很適合寬帶調(diào)制和解調(diào)應(yīng)用。且AD835需要的外圍電路非常少，配置方便。綜上論證比較，我們選用方案二作為模擬乘法器的實(shí)現(xiàn)方法。1.3低通濾波器的設(shè)計(jì)與選擇方案一：采用分立元件，搭建LC低通濾波器。方案說明：雖然電路結(jié)構(gòu)簡單，但精度不高，穩(wěn)定性差。方案二：采用高精低噪運(yùn)算放大器OP07搭建截止頻率為5KHz的二階有源低通濾波器。方案說明：可利用濾波器專用設(shè)計(jì)軟件FilterSolutions設(shè)計(jì)，得到二階低通有源濾波器電路的連接圖和頻率響應(yīng)曲線。方案三：采用LTC1564芯片搭建截止頻率為10KHz的十階低通濾波器。方案說明：LTC1564是凌力爾特公司的數(shù)控濾波器芯片，可采用經(jīng)典10KHz的十階低通濾波器電路結(jié)構(gòu)，設(shè)計(jì)簡單，濾波效果非常好，穩(wěn)定性高。綜上論證比較，我們選用方案三作為低通濾波器的實(shí)現(xiàn)方法。1.4ADC模塊的設(shè)計(jì)與選擇方案一：采用ADC芯片搭建模數(shù)轉(zhuǎn)換電路。方案說明：可選取適宜的ADC芯片，采用經(jīng)典模塊電路搭建。方案二：直接利用STM32片上的12位高速ADC模塊。方案說明：本系統(tǒng)選用的核心板STM32F103ZET6上，自帶3個(gè)12位模數(shù)轉(zhuǎn)換器，且轉(zhuǎn)換時(shí)間可達(dá)1us，多達(dá)21個(gè)輸入通道。由于單片機(jī)上的ADC已可以到達(dá)實(shí)驗(yàn)采樣要求，故我們選用方案二作為ADC模塊的設(shè)計(jì)方法，可減少外部電路的焊接。1.5被測網(wǎng)絡(luò)的設(shè)計(jì)與選擇被測網(wǎng)絡(luò)按照實(shí)驗(yàn)要求采用RLC串聯(lián)諧振網(wǎng)絡(luò)設(shè)計(jì)，圖示如下：圖1.1 RLC被測網(wǎng)絡(luò)電路圖RLC被測網(wǎng)絡(luò)的元器件值詳見電路理論分析。電路設(shè)計(jì)2.1正交掃描信號源設(shè)計(jì)電路正交掃描信號源采用AD9854芯片設(shè)計(jì)，電路詳見附圖。2.2模擬乘法器設(shè)計(jì)電路模擬乘法器采用AD835芯片設(shè)計(jì)，電路如下：圖2.1 乘法器電路2.3低通濾波器設(shè)計(jì)電路低通濾波器采用LTC1564芯片設(shè)計(jì)，搭建構(gòu)成十階的可達(dá)10KHz截止頻率的電路，圖示如下：圖2.2 低通濾波器電路2.4末級電壓抬升設(shè)計(jì)電路由于本系統(tǒng)設(shè)計(jì)檢測被測網(wǎng)絡(luò)信號為正弦波形，電壓有負(fù)值，接入ADC采樣前設(shè)計(jì)一電壓抬升電路，圖示如下：圖2.3 末級電壓抬升電路系統(tǒng)設(shè)計(jì)3.1方案總體設(shè)計(jì)描述本方案首先設(shè)計(jì)一個(gè)正交掃描信號源，可產(chǎn)生相位互為正交的雙端口正弦信號，可設(shè)置信號頻率的步進(jìn)單位。制作一個(gè)RLC串聯(lián)諧振電路作為被測網(wǎng)絡(luò)，且網(wǎng)絡(luò)通帶中心頻率為20Mhz。自制信號源產(chǎn)生的兩路正弦信號和被測網(wǎng)絡(luò)信號通過乘法器模塊，由低通濾波模塊濾除高頻分量，得到被測網(wǎng)絡(luò)的頻率，由ADC采樣信號并輸出顯示。圖3.1簡易頻率特性測試儀系統(tǒng)原理示意圖該方案在硬件電路設(shè)計(jì)上主要包含了AD9854正交掃描信號發(fā)生器、AD835模擬乘法器、LTC1564低通濾波器、末級抬升電壓電路及RLC串聯(lián)諧振被測網(wǎng)絡(luò)五個(gè)模塊，通過逐個(gè)模塊調(diào)試至整個(gè)系統(tǒng)電路連貫調(diào)試，完成根本測試實(shí)驗(yàn)要求。在軟件設(shè)計(jì)上利用了ARM編程工具和STM32核心開發(fā)板，軟件主要包含了對AD9854、串口通信、片上ADC采樣及彩屏控制局部。其中，ADC模塊采用STM32板上自帶12位高速ADC，減少了局部硬件電路的設(shè)計(jì)，容易實(shí)現(xiàn)。3.2理論分析與計(jì)算3.2.1正交掃描信號發(fā)生器的設(shè)計(jì)本設(shè)計(jì)的掃描信號發(fā)生器以AD9854芯片采用DDS技術(shù)，結(jié)合單片機(jī)程控，以產(chǎn)生兩路正交正弦信號。設(shè)計(jì)中設(shè)置AD9854為單音模式，不僅可以調(diào)制所需頻率的頻率源信號，而且可根據(jù)需要設(shè)置輸出信號的幅度、頻率和相位等，即通過改變ROM表輸出的幅度控制字實(shí)現(xiàn)幅度控制，通過改變相位累加器輸入端的頻率控制字實(shí)現(xiàn)頻率控制，通過改變相位累加器輸出端的相位控制字實(shí)現(xiàn)相位控制，從而完成相應(yīng)的幅度、頻率和相位的調(diào)制。設(shè)相位累加器的位數(shù)為N，相位控制字的值為FN，頻率控制字的位數(shù)為M，頻率控制字的值為FM，AD9854內(nèi)部工作時(shí)鐘為FC，那么最終合成信號的頻率可由式〔3-1〕來決定，合成信號的相位由式〔3-2〕來決定。F=FMFθ=2πF當(dāng)AD9854的參考時(shí)鐘頻率為270MHz時(shí)，其頻率分辨率計(jì)算：270×相位控制精度計(jì)算：360幅度控制范圍計(jì)算：20得到頻率分辨率接近10-6，相位控制精度達(dá)0.022，幅度控制范圍為72dB，完全可3.2.2低通濾波器的設(shè)計(jì)設(shè)計(jì)中為得到被測網(wǎng)絡(luò)信號的頻率特性，需要將經(jīng)過乘法器后的高頻分量濾除，由于被測網(wǎng)絡(luò)中心頻率在20MHz，故我們選用凌力爾特公司的LTC1564芯片，采用經(jīng)典電路，通過Multisim軟件搭建電路并進(jìn)行仿真調(diào)試，設(shè)計(jì)截止頻率為10KHz的低通濾波器。3.2.3RLC被測網(wǎng)絡(luò)的設(shè)計(jì)RLC串聯(lián)電路由電阻R、電感L及電容C串聯(lián)構(gòu)成，利用Multisim軟件設(shè)計(jì)被測網(wǎng)絡(luò)電路。反映RLC電路頻率特性的參數(shù)有諧振頻率f0、通頻帶寬BW和品質(zhì)因數(shù)Q，其定義如下：f0=12πBW=fH-fQ=ω其中，計(jì)算通頻帶式〔3-4〕中的fH和fL分別是回路電流由最大值增加和減少3dB時(shí)所對應(yīng)的上限頻率和下限頻率；計(jì)算品質(zhì)因數(shù)式〔3-5〕中的ω0=3.2.4特性曲線顯示1〕幅頻特性曲線采用STM32片上ADC芯片，通過DMA通道測量信號電壓值，當(dāng)ADC轉(zhuǎn)換結(jié)束以后，讀取ADC_DR存放器中的結(jié)果，通過下面的公式轉(zhuǎn)換電壓：Vtempsensor=ADC設(shè)系統(tǒng)輸出的兩路正交信號為：Ua=UUb=U經(jīng)ADC雙通道采樣后，電壓幅值計(jì)算：U=|U1據(jù)經(jīng)電壓轉(zhuǎn)換后，計(jì)算電壓增益，公式如下：AV=20lg?|在彩屏上顯示幅頻特性曲線，以線性頻率〔Hz〕為橫坐標(biāo)，以電壓增益〔dB〕為縱坐標(biāo)，顯示出被測信號的幅頻特性曲線。2〕相頻特性曲線兩路正交信號經(jīng)ADC雙通道采樣后，相位計(jì)算：Arg=arctan|U1由于信號相位計(jì)算需要函數(shù)算法，比較復(fù)雜，故采用查表法程序。在彩屏上顯示相頻特性曲線，以線性頻率〔Hz〕為橫坐標(biāo)，以相移〔℃〕為縱坐標(biāo)，顯示出被測信號的相頻特性曲線。軟件設(shè)計(jì)在本設(shè)計(jì)中，由STM32F103ZET6核心板實(shí)現(xiàn)程序的控制。其中，軟件主要完成了AD9854的信號發(fā)生控制、Usart串口通信、ADC雙通道采樣、彩屏TFT顯示的功能。系統(tǒng)框圖及流程如下：開始開始STM2初始化STM2初始化STM1初始化彩屏初始化顯示開機(jī)界面控制AD9854掃描信號發(fā)生器彩屏初始化顯示開機(jī)界面控制AD9854掃描信號發(fā)生器UasrtUasrt串口通信ADCADC雙通道采樣結(jié)束彩屏TFT結(jié)束彩屏TFT顯示特性曲線圖4.1 系統(tǒng)軟件流程框圖系統(tǒng)測試5.1測試方法本系統(tǒng)的測試過程中，模擬電路采用由前端到后端，數(shù)字電路采用先仿真再調(diào)試的方法，從逐個(gè)模塊測試完成再到模塊連接調(diào)試，直至整個(gè)系統(tǒng)電路完成測試要求。5.2測試工具1〕直流穩(wěn)壓源2)安捷倫數(shù)字示波器3〕函數(shù)信號發(fā)生器4〕數(shù)字頻譜儀5〕數(shù)字萬用表5.3各模塊測試過程5.3.1掃頻信號發(fā)生器的測試使用直流穩(wěn)壓源對AD9854制成的掃描信號發(fā)生器進(jìn)行正負(fù)5V供電，可承載電流不超過1A，將掃描信號發(fā)生器連接單片機(jī)，下載控制程序，通過數(shù)字示波器顯示輸出的I路及Q路信號，現(xiàn)列出一組典型實(shí)驗(yàn)數(shù)據(jù)。表5.1 掃描信號發(fā)生器測試結(jié)果

理論電壓〔Vpp/V〕實(shí)際電壓〔Vpp/V〕理論頻率〔f/MHz〕實(shí)際頻率〔f/MHz〕I路信號2.001.9820.020.0Q路信號2.001.9620.020.0I、Q兩路正弦信號呈正交關(guān)系，示波器上測量計(jì)算兩路信號相位呈90度。輸出電壓和頻率誤差小于5%。通過頻譜儀接入電路輸出信號，掃描信號發(fā)生器完全可產(chǎn)生1M-40MHz范圍的信號，精度可達(dá)10-4；且頻率步進(jìn)可調(diào)，達(dá)100KHz精度。5.3.2乘法器模塊的測試?yán)脭?shù)字函數(shù)發(fā)生器產(chǎn)生兩路正交正弦信號，接入乘法器模擬電路，現(xiàn)列出一組典型信號測試結(jié)果：兩路輸入電壓峰峰值均為Vp-p=2.00V，頻率均為F=20MHz。表5.2 乘法器測試結(jié)果

理論電壓〔Vpp/V〕實(shí)際電壓〔Vpp/V〕理論頻率〔f/MHz〕實(shí)際頻率〔f/MHz〕I路信號2.001.9820.020.0Q路信號2.002.0020.020.0輸出信號1.000.9840.039.9綜上數(shù)據(jù)可看出，模擬乘法器模塊工作正常，輸出信號誤差小于2%。5.3.3輸入輸出阻抗的測試?yán)脭?shù)字萬用表測試該系統(tǒng)的輸入阻抗和輸出阻抗，即測量被測網(wǎng)絡(luò)兩端的Ri和RO，可達(dá)50Ω。5.3.4RLC被測網(wǎng)絡(luò)的測試連接RLC被測網(wǎng)絡(luò)，利用調(diào)節(jié)頻率法測量電路的諧振頻率。電路輸入端接入數(shù)字函數(shù)發(fā)生器，保持信號源輸出電壓US不變，改變信號發(fā)生器的頻率，將電路輸出端接入數(shù)字頻譜儀觀察其輸出的電壓值。當(dāng)輸出電壓UR的讀數(shù)到達(dá)最大值〔即電流到達(dá)最大值〕時(shí)，其所對應(yīng)的頻率值即為諧振頻率或中心頻率。設(shè)置數(shù)字函數(shù)發(fā)生器輸出電壓為2.0V，調(diào)節(jié)信號頻率，取一組調(diào)節(jié)頻率法測試結(jié)果列示如下：表5.3RLC被測網(wǎng)絡(luò)測試結(jié)果信號源頻率〔f/MHz〕

17.018.019.020.021.022.023.0測量電壓〔U0/V〕1.321.581.801.981.781.541.30由上表數(shù)據(jù)可得，RLC網(wǎng)絡(luò)的中心頻率為20MHz，誤差小于5%；且其通頻帶寬約在17.5MHz-22.5MHz范圍內(nèi)，品質(zhì)因數(shù)約4。結(jié)論本設(shè)計(jì)很好的滿足了題目要求，對各模塊和整體系統(tǒng)的測試根本完成。在設(shè)計(jì)中對于由AD9854搭建的掃描信號發(fā)生器花費(fèi)了很多調(diào)試時(shí)間。通過本次設(shè)計(jì)，我們不僅熟練掌握各種儀器設(shè)備的使用調(diào)節(jié)，同時(shí)很大程度上提高了動(dòng)手能力和處理問題的能力，受益匪淺！參考文獻(xiàn)黃智偉全國大學(xué)生電子設(shè)計(jì)競賽制作實(shí)訓(xùn)北京航空航天大學(xué)出版社黃智偉全國大學(xué)生電子設(shè)計(jì)競賽技能訓(xùn)練北京航空航天大學(xué)出版社謝嘉奎，宣月清.電子線路〔非線性局部〕高等教育出版社童詩白，華成英.模擬電子技術(shù)根底〔第四版〕高等教育出版社附錄附錄一：元件清單本設(shè)計(jì)系統(tǒng)所用的主要元件清單如下所示：序號型號器件封裝說明1AD835DIP乘法器2LTC1564SSOP8階低通濾波器3REF3033SSOP3.3V基準(zhǔn)電壓4ua741DIP通用運(yùn)放5OPA727SSOP通用運(yùn)放6假設(shè)干電阻電容表7.1 系統(tǒng)元件清單列表附錄二：AD9854掃描信號發(fā)生器設(shè)計(jì)電路AD9854的高速DDS模塊硬件原理圖如下所示：圖7.1 AD9854掃描信號發(fā)生器硬件原理圖附錄三：系統(tǒng)總體設(shè)計(jì)電路本系統(tǒng)總體硬件設(shè)計(jì)原理圖如下所示：圖7.2 系統(tǒng)總體硬件原理圖附錄四：主要程序清單/******************************************************************************AD9854控制程序：******************************************************************************/voidSetAD9854Frequency(ucharucFreWordAdd,ulongulFreqVal){ucharFreqWord[6];ucharCount=6,Adress;ulongFreqBuf;Adress=ucFreWordAdd;FreqBuf=(ulFreqVal*FRETMP_Low);FreqWord[0]=(FreqBuf%0x100)&0xff;FreqBuf/=0x100;FreqBuf+=(ulFreqVal*FRETMP_MIDDLE);FreqWord[1]=(FreqBuf%0x100)&0xff;FreqBuf/=0x100;FreqBuf+=(ulFreqVal*FRETMP_HIGH);FreqWord[2]=(FreqBuf%0x100)&0xff;FreqBuf/=0x100;FreqWord[3]=(FreqBuf%0x100)&0xff;FreqBuf/=0x100;FreqWord[4]=(FreqBuf%0x100)&0xff;FreqWord[5]=(FreqBuf/0x100)&0xff;for(Count=6;Count;) {AD9854_WriteByte(Adress++,FreqWord[--Count]); AD9854_WR_0; AD9854_WR_1; } AD9854_UDCLK_1; AD9854_UDCLK_0;}voidSetAD9854Amplitude(ucharucChannel,uintuiAmpVal){ucharAmpWord[2];uintAmpBuf;AmpWord[0]=(u8)(((u16)(uiAmpVal*4096/5))%256);AmpWord[1]=(u8)(((u16)(uiAmpVal*4096/5))/256);if(ucChannel==I) { AD9854_WR_0; AD9854_WR_1; AD9854_WR_0; AD9854_WR_1; }if(ucChannel==Q) { AD9854_WR_0; AD9854_WR_1; AD9854_WR_0; AD9854_WR_1; } AD9854_UDCLK_1; AD9854_UDCLK_0;}voidSetAD9854Phase(ucharucPhaAdjRegAdd,uintuiPhaVal){ucharPhaWord[2];uintPhaBuf;PhaBuf=(uiPhaVal*0x2d);PhaWord[0]=(PhaBuf%0x100)&0xff;PhaWord[1]=(PhaBuf/0x100)&0xff;AD9854_WriteByte(ucPhaAdjRegAdd,PhaWord[1]); AD9854_WR_0; AD9854_WR_1;AD9854_WriteByte(ucPhaAdjRegAdd+1,PhaWord[0]); AD9854_WR_0; AD9854_WR_1; AD9854_UDCLK_1; AD9854_UDCLK_0;}/******************************************************************************Uarst串口初始化程序：******************************************************************************/voidUSART1_Configuration(void){USART_InitTypeDefUSART_InitStructure;USART_ClockInitTypeDefUSART_ClockInitStructure;USART_InitStructure.USART_BaudRate=115200;USART_InitStructure.USART_WordLength=USART_WordLength_8b;USART_InitStructure.USART_StopBits=USART_StopBits_1;USART_InitStructure.USART_Parity=USART_Parity_No;USART_InitStructure.USART_HardwareFlowControl=USART_HardwareFlowControl_None;USART_InitStructure.USART_Mode=USART_Mode_Rx|USART_Mode_Tx;/*ConfiguretheUSART1*/USART_Init(USART1,&USART_InitStructure);USART_ClockInitStructure.USART_Clock=USART_Clock_Disable;USART_ClockInitStructure.USART_CPOL=USART_CPOL_Low;USART_ClockInitStructure.USART_CPHA=USART_CPHA_2Edge;USART_ClockInitStructure.USART_LastBit=USART_LastBit_Disable;USART_ClockStructInit(&USART_ClockInitStructure);}/******************************************************************************ADC采樣程序：******************************************************************************/voidDAC_Configuration(void){DAC_InitTypeDefDAC_InitStructure;DAC_Cmd(DAC_Channel_1,ENABLE);DAC_StructInit(&DAC_InitStructure);DAC_InitStructure.DAC_Trigger=DAC_Trigger_Software;DAC_InitStructure.DAC_WaveGeneration=DAC_WaveGeneration_None;DAC_InitStructure.DAC_LFSRUnmask_TriangleAmplitude=DAC_TriangleAmplitude_4095;DAC_InitStructure.DAC_OutputBuffer=DAC_OutputBuffer_Enable;DAC_Init(DAC_Channel_1,&DAC_InitStructure);DAC_Cmd(DAC_Channel_1,ENABLE);//DAC_SetChannel1Data(DAC_Align_12b_R,0x0000);DAC_SoftwareTriggerCmd(DAC_Channel_1,ENABLE);}voidADC_Configuration(void){ADC_InitTypeDefADC_InitStructure;/*ConfiguretheADC1*/ADC_InitStructure.ADC_Mode=ADC_Mode_Independent;ADC_InitStructure.ADC_ScanConvMode=ENABLE;ADC_InitStructure.ADC_ContinuousConvMode=ENABLE;ADC_InitStructure.ADC_ExternalTrigConv=ADC_ExternalTrigConv_None;ADC_InitStructure.ADC_DataAlign=ADC_DataAlign_Right;ADC_InitStructure.ADC_NbrOfChannel=1;ADC_Init(ADC1,&ADC_InitStructure);/*ADC2regularchannel5configuration*/ADC_RegularChannelConfig(ADC1,ADC_Channel_3,1,ADC_SampleTime_1Cycles5);ADC_DMACmd(ADC1,ENABLE);/*EnableADC2*/ADC_Cmd(ADC1,ENABLE);/*EnableADC2resetcalibarationregister*/ADC_ResetCalibration(ADC1);/*ChecktheendofADC2resetcalibrationregister*/while(ADC_GetResetCalibrationStatus(ADC1));/*StartADC2calibaration*/ADC_StartCalibration(ADC1);/*ChecktheendofADC2calibration*/while(ADC_GetCalibrationStatus(ADC1));/*StartADC2SoftwareConversion*/ADC_SoftwareStartConvCmd(ADC1,ENABLE);}voidDMA_Configuration(void){DMA_InitTypeDefDMA_InitStructure;DMA_DeInit(DMA1_Channel1);DMA_InitStructure.DMA_PeripheralBaseAddr=ADC1_DR_Address;DMA_InitStructure.DMA_MemoryBaseAddr=(u32)&ADCConvertedValue;DMA_InitStructure.DMA_DIR=DMA_DIR_PeripheralSRC;DMA_InitStructure.DMA_BufferSize=1024;DMA_InitStructure.DMA_PeripheralInc=DMA_PeripheralInc_Disable;DMA_InitStructure.DMA_MemoryInc=DMA_MemoryInc_Enable;DMA_InitStructure.DMA_PeripheralDataSize=DMA_PeripheralDataSize_HalfWord;DMA_InitStructure.DMA_MemoryDataSize=DMA_MemoryDataSize_HalfWord;DMA_InitStructure.DMA_Mode=DMA_Mode_Circular;DMA_InitStructure.DMA_Priority=DMA_Priority_High; DMA_InitStructure.DMA_M2M=DMA_M2M_Disable;DMA_Init(DMA1_Channel1,&DMA_InitStructure);DMA_ITConfig(DMA1_Channel1,DMA_IT_TC,ENABLE); /*EnableDMA1channel1*/DMA_Cmd(DMA1_Channel1,ENABLE);}/******************************************************************************TFT彩屏局部算法程序：******************************************************************************/voidLCD_Writ_Bus(charVH,charVL)//并行數(shù)據(jù)寫入函數(shù){datah_change(VH);//LCD_DataPortH=VH;datal_change(VL);//LCD_DataPortL=VL;GPIO_ResetBits(LCD_GRP,LCD_WR);//LCD_WR=0;GPIO_SetBits(LCD_GRP,LCD_WR);//LCD_WR=1;}voidLcd_Write_Com(charVH,charVL) //發(fā)送命令-8位參數(shù){GPIO_ResetBits(LCD_RS_GRP,LCD_RS);//LCD_RS=0;LCD_Writ_Bus(VH,VL);}voidLcd_Write_Data(charVH,charVL)//發(fā)送數(shù)據(jù)-8位參數(shù){GPIO_SetBits(LCD_RS_GRP,LCD_RS);//LCD_RS=1;LCD_Writ_Bus(VH,VL);}voidLcd_Write_Com_Data(intcom,intval) //發(fā)送數(shù)據(jù)命令{Lcd_Write_Com(com>>8,com);Lcd_Write_Data(val>>8,val);}voidAddress_set(unsignedintx1,unsignedinty1,unsignedintx2,unsignedinty2){Lcd_Write_Com(0x00,0x46);Lcd_Write_Data(x2,x1);Lcd_Write_Com(0x00,0x47);Lcd_Write_Data(y2>>8,y2);Lcd_Write_Com(0x00,0x48);Lcd_Write_Data(y1>>8,y1);Lcd_Write_Com(0x00,0x20);Lcd_Write_Data(x1>>8,x1);Lcd_Write_Com(0x00,0x21);Lcd_Write_Data(y1>>8,y1);Lcd_Write_Com(0x00,0x22);}//畫點(diǎn)//POINT_COLOR:此點(diǎn)的顏色voidLCD_DrawPoint(unsignedintx,unsignedinty,unsignedintPOINT_COLOR) //把函數(shù)體內(nèi)的xy調(diào)換{if(x>319)x=319;elseif(x<0)x=0;if(y>239)y=239;elseif(y<0)y=0;Address_set(y,x,y,x);//設(shè)置光標(biāo)位置Lcd_Write_Data(POINT_COLOR>>8,POINT_COLOR);}//畫線//x1,y1:起點(diǎn)坐標(biāo)//x2,y2:終點(diǎn)坐標(biāo)voidLCD_DrawLine(unsignedintx1,unsignedinty1,unsignedintx2,unsignedinty2,iu16color){u16t;intxerr=0,yerr=0,delta_x,delta_y,distance;intincx,incy,uRow,uCol;delta_x=x2-x1;//計(jì)算坐標(biāo)增量delta_y=y2-y1;uRow=x1;uCol=y1; if(delta_x>0)incx=1;//設(shè)置單步方向 elseif(delta_x==0)incx=0;//垂直線else{incx=-1;delta_x=-delta_x;}if(delta_y>0)incy=1; elseif(delta_y==0)incy=0;//水平線else{incy=-1;delta_y=-delta_y;} if(delta_