【正文】 浙江科技學(xué)院信息與電子工程學(xué)院 2021 屆本科畢業(yè)設(shè)計（論文） I 摘要 設(shè)計一個 基于單片機(jī)的電子秤。 這個系統(tǒng)的核心部件是 STC89C52 單片機(jī) 。 這個電子 秤 的主要分硬件和軟件部分，硬件 電路構(gòu)成有測量電路 模塊 ，差放電路 模塊 ， A/D 轉(zhuǎn)換模塊 ，單片機(jī) 模塊 、顯示 模塊 。測量電路利用 傳感器 將物體的重量信號 轉(zhuǎn)換 成相應(yīng)大小的電信號 ， 之后這個電信號會經(jīng)過差動放大電路使這個電信號的電壓值放大到可以被 AD 轉(zhuǎn)換模塊正確而且快速的識別處理，放大之后經(jīng)過AD 轉(zhuǎn)換變成數(shù)字信號每個信號對應(yīng)一個物體的重量，最后這個信號流經(jīng)單片機(jī)進(jìn)行信息處理再從顯示屏顯示輸出 。 系統(tǒng)通過 讀取矩陣鍵盤輸入的數(shù)字顯示總價和單價，并 可以儲存 5 次稱重的數(shù)據(jù)。這些硬件電路配合軟件部分 經(jīng) 過 調(diào)試 外加 測試， 這 系統(tǒng)各 個 性能 目標(biāo)已 達(dá)到設(shè)計 要求，可以投放使用。 關(guān)鍵詞 ： 單片機(jī)； 傳感器 ；液晶顯示屏 浙江科技學(xué)院信息與電子工程學(xué)院 2021 屆本科畢業(yè)設(shè)計（論文） II ABSTRACT Design a microcontroller based electronic ponents of this system is STC89C52 main points of this electronics hardware and software ponents,measuring circuit has a circuit configuration of hardware modules,differential amplifier circuit module, A / D converter module, microcontroller module, display by a sensor circuit to convert the weight signal into an electrical signal corresponding to the object size,after this the electrical signal through the differential amplifier circuit so that the voltage value of the electrical signal is amplified to the AD converter module can be correctly and fast recognition process,then amplification through the AD converter into a digital signal for each signal corresponds to the weight of an object,this signal flow through the microcontroller for information processing and then output from the by reading the digital display matrix keyboard input price and the price,and can store five times the weighing hardware with the software part of the circuit after missioning additional testing,this system has various performance goals to meet the design requirements,able to put to use. Keywords: microcontroller； Sensor； Display 浙江科技學(xué)院信息與電子工程學(xué)院 2021 屆本科畢業(yè)設(shè)計（論文） III 目錄 摘要 .................................................................................................................................... I ABSTRACT ...................................................................................................................... II 目錄 .................................................................................................................................. III 第 1 張 引言 ..................................................................................................................... 1 背景 ........................................................................................................................ 1 設(shè)計指標(biāo) ................................................................................................................ 2 電子秤原理 ............................................................................................................ 2 設(shè)計思路 ................................................................................................................ 3 第 2 章 系統(tǒng)方案分析與選型 ......................................................................................... 4 傳感器選擇 ............................................................................................................ 4 放大和 A/D 轉(zhuǎn)換電路選擇 .................................................................................... 4 顯示電路選擇 ........................................................................................................ 4 第 3 章 電子秤系統(tǒng)的硬件設(shè)計 ..................................................................................... 6 單片機(jī)模塊 ............................................................................................................ 6 功能特點(diǎn) .......................................................................................................... 6 單片機(jī)引腳定義 .............................................................................................. 6 傳感器模塊 ............................................................................................................ 8 AD 轉(zhuǎn)換模塊 ......................................................................................................... 10 HX711 介紹 .................................................................................................... 10 AD 采樣電路 .................................................................................................. 12 鍵盤輸入模塊 ...................................................................................................... 12 顯示模塊 .............................................................................................................. 13 聲光報警模塊 ...................................................................................................... 14 第 4