【正文】 31 附錄一 源程 序 ............................................................................................................................. 32 附錄二 電路原理圖 ..................................................................................................................... 40 附錄三 硬件實物圖 ....................................................................................... 錯誤 !未定義書簽。 AT89S52 摘要 2 目錄 摘要 ................................................................................................................................................. 0 第一章 緒論 ................................................................................................................................... 3 課題背景、目的及意義 ................................................................................................... 3 設計要求和任務 ............................................................................................................... 3 單片機概述 ....................................................................................................................... 3 單片機的發(fā)展 ......................................................................................................... 4 單片機的應用 ......................................................................................................... 5 AT89S52 單片機 ................................................................................................................ 6 信號發(fā)生器概述 ............................................................................................................... 8 本論文主要研究的內(nèi)容 ................................................................................................... 9 第二章 系統(tǒng)設計方案 ............................................................................................................... 11 系統(tǒng)分析 ......................................................................................................................... 11 問題定義 ............................................................................................................... 11 系統(tǒng)可行性分析 ................................................................................................... 11 系統(tǒng)需求分析 ................................................................................................................. 12 總體方案設計 ................................................................................................................. 13 第三章 硬件設計 ....................................................................................................................... 13 總體硬件設計 ................................................................................................................. 14 系統(tǒng)模塊設計 ................................................................................................................. 14 電源設計 ............................................................................................................... 14 顯示器接口設計 ..................................................................... 錯誤 !未定義書簽。 SCM。 [關鍵詞 ]：函數(shù)信號發(fā)生器；單片機； DAC0832； AT89S52 摘要 1 Abstract Signal generator is a mon signal source, can produce an analog voltage waveform， widely used in electronic circuits, automatic control systems, and teaching experiments and other fields. waveform generator and a special price of expensive . Currently used mostly function signal generator signal generator。此電路清晰，出現(xiàn)故障容易查 找錯誤，操作簡單、方便。外圍電路實現(xiàn)數(shù)模轉換和信號波形放大。在單片機的輸出端口接 DAC0832進行 D/A轉換，再通過運算放大器進行波形幅度調(diào)整，最后輸出波形接在示波器上顯示。輸出波形的頻率和種類可用程序控制改變。設計采用 AT89S52單片機和一片 DAC0832數(shù)模轉換器以及一些外圍電路組成低頻信號發(fā) 生器。目前使用的信號發(fā)生器大部分是函數(shù)信號發(fā)生器，它具有價格低、性能高和在低頻范圍內(nèi)穩(wěn)定性好、操作方便、體積小、耗電少等特點。 摘要 多功能 信號發(fā)生器 是 是一種常用的信號源 ，能產(chǎn)生模擬電壓波形 ，廣泛地應用于電子電路、自動控制系統(tǒng)和教學實驗等領域。且特殊波形發(fā)生器的價格昂貴。 本設計 信號 發(fā)生器采用 AT89S52單片機作為控制核心，外圍采用 了包括電源模塊、數(shù)字 /模擬 轉換電路（ DAC0832）、運放電路（ LM324）、 鍵盤模塊 等。此發(fā)生器能產(chǎn)生從 1HZ1MHZ的低失真 正弦波，三角波，方波，矩形波，鋸齒波 等 信號 。在單片機上加外圍按鍵，通過按鍵控制波形頻率的增減以及波形的選擇。 本設計根據(jù)要求主要研究了軟件編程實現(xiàn)波形和頻率的可調(diào)。由于采用了 LM324運算放大器和穩(wěn)壓電路，使其電路更加具有較高的穩(wěn)定性能，性能比高。具有典型性。 it has low cost, high performance and good stability at low frequency within the range, easy operation, small size, power consumption and so on. The design generator using AT89S52 microcontroller as the control, external analog / digital conversion circuit (DAC0832), operational amplifiers circuit (LM324), buttons and LCD liquid crystal display circuit.， etc..Design using AT89S52 microcontroller and a DAC0832 DAC as well as some peripheral circuit a low period of wave. The generator can produce from the 10100HZ ,2002020HZ, lowdistortion sine wave, triangle wave, square wave signal, etc.. 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. The major design required study a software programming waveform and frequency adjustable. External digitalanalog conversion circuit and signal waveforms to enlarge. Because use the LM324 operational amplifier and voltage regulator circuit, so the circuit is with higher performance, the high performance. The circuit clear, easy to find failure error, simple and convenient. Is a typical circuit . Key words： signal generator。 DAC0832。 復位與時鐘電路設計 ........................................................................................... 15