【正文】 件電路包括鍵控制模塊、顯示模塊、輸入信號整形模塊以及單片機(jī)和 CPLD 主控模塊。利用單片機(jī)完成整個(gè)測量電路的測試控制、數(shù)據(jù)處理和顯示輸出。等精度的測量方法不但具有較高的測量精度，而且在整個(gè)頻率區(qū)域保持恒定的測試精度。中文題目：基于 CPLD和單片機(jī)的頻率測量計(jì)的設(shè)計(jì)外文題目：THE DESIGN OF FREQUENCY MEASUREMENT BASED ON CPLD AND SINGLE CHIP MICYOCO 畢業(yè)設(shè)計(jì)（論文）共 70 頁 圖紙共 2 張完成日期 20221 年 6 月 答辯日期 20221 年 6 月摘要本文主要論述了利用 CPLD 進(jìn)行測頻計(jì)數(shù)，單片機(jī)實(shí)施控制實(shí)現(xiàn)等精度頻率計(jì)的設(shè)計(jì)過程。該頻率計(jì)利用等精度的設(shè)計(jì)方法，克服了基于傳統(tǒng)測頻原理的頻率計(jì)的測量精度隨被測信號頻率的下降而降低的缺點(diǎn)。該頻率計(jì)利用 CPLD 來實(shí)現(xiàn)頻率的測量計(jì)數(shù)。本文詳細(xì)論述了硬件電路的組成和單片機(jī)的軟件控制流程。設(shè)計(jì)器件采用Atmel 公司的單片機(jī) AT89C51 和 Altera 公司的 FPGA 芯片 MAX7000 系列EPM7128SLC8415。關(guān)鍵詞：單片機(jī)；CPLD；頻率計(jì)；測頻；等精度AbstractThe reach pape rmainly discusses the design process of equalaccuracy frequency meter that uses CPLD to count the frequency measurement and frequency meter is also controled by single chip puter. The frequency meter makes use of equalaccuracy design that can overe the disadvantage of traditional measuring principle, which precision declines as measured signal frequency does. The equalaccuracy measurement not only has higher measuring precision, but also can keep invariable measuring precision in whole area of frequency.This frequency meter uses CPLD to realize the measuring count of frequency. Single chip puter pletes the test control、data processing and display output of the system.This essay discusses the pose of hardware circuit and software control flow of single chip puter in detail. Hardware circuit includes key control module、display module, plastic module of input signal、single chip puter control module and CPLD main control module.The frequency meter adopts single chip puter AT89C51 of Atmel pany and EPM7128SLC8415 of Altera pany. Key control module has 1 function key and 3 time selection key. A chip 74LS165 pletes the key value input. Display module uses eight 74LS165s to realize the serial display of LED. First, the measuring signal amplitude is limited. Second, the single is amplified by two class direct coupling amplifier. Finally, the signal inputs CPLD after it is trimed by Smitter trigger. Standard frequency is 40MHZ. Software program of single chip puter is writed by assembly language. Some of software program is corresponded to every hardware part, the others includ data count and transform.Key Words：SCM。 Frequency meter。 Equalprecision目錄摘要 .............................................................IABSTRACT ........................................................II1 緒論 ..........................................................1 頻率計(jì)基礎(chǔ)知識 ...............................................1 對靈敏度和準(zhǔn)確度的要求 .............................................................................1 測量儀器的準(zhǔn)確度的選擇 .............................................................................2 微波計(jì)數(shù)器的使用 .........................................................................................2 技術(shù)背景及發(fā)展趨勢 ...........................................3 EDA 技術(shù)的發(fā)展及其應(yīng)用 .......................................4 單片機(jī)概論 ...................................................5 頻率計(jì)的設(shè)計(jì)內(nèi)容和意義 .......................................62 設(shè)計(jì)理論基礎(chǔ) ..................................................8 CPLD/FPGA 設(shè)計(jì)意義 ...........................................8 EDA..................................................................................................................8 CPLD(復(fù)雜可編程邏輯器件) .......................................................................8 FPGA（現(xiàn)場可編程門陣列） ......................................................................9 FPGA 和 CPLD 的選擇 .................................................................................9 頻率測量原理 .................................................9 頻率測量 .......................................................................................................10 周期測量 .......................................................................................................10 等精度測頻法 ...............................................................................................11 方案設(shè)計(jì) ....................................................13 基于單片機(jī)的方案 .......................................................................................13 基于 CPLD/FPGA 和單片機(jī)相結(jié)合的方案 .............................................14 方案論證與選擇 ...........................................................................................153 單元模塊設(shè)計(jì) .................................................16 系統(tǒng)組成 ....................................................16 鍵控制模塊 ..................................................17 串行輸出移位寄存器（74LS165 ） .........................................................17 鍵盤電路 .......................................................................................................18 顯示模塊 ....................................................19 顯示電路設(shè)計(jì) ...............................................................................................19 74LS164(串入并出移位寄存器) ...............................................................21 電源模塊 ....................................................21 輸入信號整形模塊 ............................................22 信號整形電路 ...............................................................................................22 施密特觸發(fā)器 ...............................................................................................23 單片機(jī)主控模塊 ..............................................24 AT89C51 單片機(jī)性能 ................................................................................24 單片機(jī)控制電路 ...........................................................................................31 測頻模塊的工作原理及設(shè)計(jì) ....................................32 CPLD 的結(jié)構(gòu)與功能介紹 ...........................................................................32 CPLD 引腳分布 ............................................................................................33 CPLD 模塊邏輯設(shè)計(jì) ...................................................................................3438 其它電路 ......