【正文】 指導(dǎo)教師： 胡敏 二〇 一五 年月 HAOJING COLLEGESHAANXI UNIVERSITY OFSCIENCE＆ TECHNOLOGY I Electronic music box based on MCU ABSTRACT The ease of use and versatility make SCM widely used in variousmicrocontrol system. This paper introduces a SCMbased electronic music box design, which is based on AT89C2051 single chip microputer as control core, supplemented by some peripheral elements, using assembly language programming to realize music playing functions. Utilizing the residuary port P1 on the SCM, it extends the function of this music box, which could make LED lattice shift display. The electric circuit construction of the whole system is simple, the function has high reliability and the experiment test results satisfy the request. This paper emphasize introduces the design principle of the system, hardware design and software programming ideas. Key words:SCM,AT89C2051,music box,LED shift display II 基于單片機(jī)的電子音樂(lè)盒 摘 要 單片機(jī)的易用性與多功能性使它廣泛應(yīng)用于各種微控制系統(tǒng)。本文介紹了一種基于單片機(jī)的電子音樂(lè)盒的設(shè)計(jì)，它是以 AT89C2051 單片機(jī)為控制核心，輔以一些外圍器件，采用匯編語(yǔ)言編寫(xiě)程序，實(shí)現(xiàn)音樂(lè)播放功能。整個(gè)系統(tǒng)電路結(jié)構(gòu)簡(jiǎn)單，可靠性能高，測(cè)試結(jié)果滿足設(shè)計(jì)要求。 關(guān)鍵字 ：?jiǎn)纹瑱C(jī)、 AT89C205音樂(lè)盒、 LED 移位顯示 III 目 錄 第 1 章 前 言 ............................................................................................................................ 1 單片機(jī)介紹 ........................................................................................................ 1 單片機(jī)音樂(lè) ........................................................................................................ 2 第 2 章 設(shè)計(jì)要求及理論基礎(chǔ) ................................................................................................. 3 設(shè)計(jì)要求 ............................................................................................................ 3 基本要求 ................................................................................................. 3 創(chuàng)新部分 ................................................................................................. 3 成果形式 ................................................................................................. 3 相關(guān)音樂(lè)知識(shí) .................................................................................................... 3 單片機(jī)產(chǎn)生音頻脈沖原理 ................................................................................ 4 音符頻率 ................................................................................................. 4 定時(shí) /計(jì)數(shù)器 0 產(chǎn)生音符頻率 ............................................................... 5 單片機(jī)實(shí)現(xiàn)音樂(lè)的節(jié)拍 .................................................................................... 6 音頻功放 ............................................................................................................ 7 小結(jié) .................................................................................................................... 7 第 3 章 硬件設(shè)計(jì) ...................................................................................................................... 8 方案選取 ............................................................................................................ 8 單片機(jī)的選取 ......................................................................................... 8 音頻放大電路的選擇 ............................................................................. 9 中斷方式 ............................................................................................... 11 LED 顯示方式 ....................................................................................... 11 LED 驅(qū)動(dòng)電路 ....................................................................................... 12 硬件電路的實(shí)現(xiàn) .............................................................................................. 12 AT89C2051 單片機(jī)硬件結(jié)構(gòu) ............................................................... 12 時(shí)鐘與復(fù)位電路 ................................................................................... 16 選擇按鍵輸入電路 ............................................................................... 17 音頻發(fā)生器 ........................................................................................... 18 音頻放大器 ........................................................................................... 18 小結(jié) .................................................................................................................. 26 第 4 章 軟件設(shè)計(jì) .................................................................................................................... 27 LED 移位顯示程序 .......................................................................................... 27 IV 音樂(lè)盒功能程序 .............................................................................................. 32 小結(jié) .................................................................................................................. 35 第 5 章 軟硬件調(diào)試 ............................................................................................................... 36 硬件調(diào)試 .......................................................................................................... 36 軟件調(diào)試 .......................................................................................................... 36 性能 測(cè)試 .......................................................................................................... 37 LED 顯示畫(huà)面 ....................................................................................... 37 單片機(jī)輸出樂(lè)曲音頻圖 ...................................................................... 37 可靠性分析 ........................................................................................... 38 小結(jié) .................................................................................................................. 39 第 6 章 結(jié)語(yǔ) ............................................................................................................................ 40 致謝 .................................................................