【正文】 e apparatus.Key Words:AT89C51?？梢哉f,此設計所完成的電子秤很大程度上滿足了應用需求。本系統(tǒng)主要由單片機來控制，測量物體重量部分由稱重傳感器及 A/D 轉換器組成，加上顯示單元，此電子秤俱備了功能多、性能價格比高、功耗低、系統(tǒng)設計簡單、使用方便直觀、速度快、測量準確、自動化程度高等特點。 I畢業(yè)論文設計基于 51 單片機的商業(yè)用智能電子秤設計 II摘 要隨著微電子技術的應用，市場上使用的傳統(tǒng)稱重工具已經滿足不了人們的要求。為了改變傳統(tǒng)稱重工具在使用上存在的問題，在本設計中將智能化、自動化、人性化用在了電子秤重的控制系統(tǒng)中。本系統(tǒng)以 AT89C51 單片機為主控芯片，外圍附以稱重電路、顯示電路、鍵盤電路等構成智能稱重系統(tǒng)電路板，從而實現(xiàn)自動稱重系統(tǒng)的各種控制功能。關鍵詞 AT89C51 稱重傳感器 A/D 轉換器 LCD 顯示器 IIIAbstractWith the application of microelectronics technology, tradition ponderation instrument used in market has been not satisfaction with hunman requirements already. In order to make up for the traditional apparatus shorting, we improve the apparatus39。 weighing sensor。 LCD Monitor IV I目 錄摘 要 ...........................................................................................................................................................................IABSTRACT.......................................................................................................................................................................II第一章 緒論 ............................................................................................................................................................1 電子秤的概述 ................................................................................................................................................1 設計目的 .........................................................................................................................................................2第二章 系統(tǒng)方案的設計 ................................................................................................................................1 設計要求 .........................................................................................................................................................1 進度安排 .........................................................................................................................................................1 電子秤的工作原理 ......................................................................................................................................1 系統(tǒng)的整體設計思路 .................................................................................................................................2第三章 系統(tǒng)硬件電路設計 ..............................................................................................................................5 壓力傳感器 .....................................................................................................................................................5 前級放大器 .....................................................................................................................................................8 反相比例運算電路 .............................................................................................................................8 前級放大電路 ....................................................................................................................................10 A/D 轉換器 ....................................................................................................................................................11 方案比較 ..............................................................................................................................................11 ADC0832 芯片介紹 ............................................................................................................................12 采樣電路圖 .........................................................................................................................................12 控制器 ............................................................................................................................................................13 AT89C51 芯片介紹 ............................................................................................................................14 單片機最小系統(tǒng) ...............................................................................................................................16 輸入鍵盤 ........................................................................................................................................................17 矩陣鍵盤仿真及接線圖 .................................................................................................................18 矩陣鍵盤工作原理 ...........................................................................................................................18 輸出顯示 .......................................................................................................................................................18 II LCD12864 介紹 ...................................................................................................................................19 LCD 顯示電路圖 .................................................................................................................................21 LCD 的驅動 ..........................................................................................................................................21第四章 系統(tǒng)軟件的設計 .................................................................................................................................22 主程序設計 ...................................................................................................................................................22 A/D 轉換啟動及數(shù)據(jù)讀取程序設計 ....................................................................................................23 鍵盤子程序 ...................................................................................................................................................24 顯示子程序 ...................................................................................................................................................25第五章 仿真調試 .....................................................................