摘  要

　　　

　　　該設(shè)計(jì)以51系列單片機(jī)AT89S52為控制核心，實(shí)現(xiàn)電子秤的基本控制功能。在設(shè)計(jì)系統(tǒng)時，為了更好利用AT89S52的資源，系統(tǒng)擴(kuò)展了電子日歷時鐘與溫度檢測模塊，系統(tǒng)可以分為最小系統(tǒng)、數(shù)據(jù)采集、人機(jī)交互界面和系統(tǒng)電源、時鐘、溫度檢測和語言報(bào)數(shù)六大部分。最小系統(tǒng)部分主要包括AT89S52和經(jīng)典復(fù)位電路；數(shù)據(jù)采集部分由稱重傳感器、信號放大和A/D轉(zhuǎn)換部分組成，信號放大和A/D轉(zhuǎn)換部分主要由專用型高精度24位AD轉(zhuǎn)換芯片HX711實(shí)現(xiàn)；人機(jī)交互界面為鍵盤輸入和點(diǎn)陣式液晶顯示，主要使用4*4矩陣鍵盤和太陽人公司的1602液晶顯示器，可以方便的輸入數(shù)據(jù)和直觀的顯示數(shù)據(jù)；系統(tǒng)電源以外接9V電源和板上電源電路為核心設(shè)計(jì)電路以提供系統(tǒng)正常工作電源；時鐘模塊主要由時鐘芯片DS1302和時鐘電路組成；溫度檢測主要由DS18B20實(shí)現(xiàn)；語音報(bào)數(shù)模塊可語音報(bào)讀時間和電子秤系統(tǒng)的重量、單價(jià)、金額等語音內(nèi)容，主要由SC1010B實(shí)現(xiàn)。軟件部分應(yīng)用單片機(jī)C語言進(jìn)行編程，實(shí)現(xiàn)了該設(shè)計(jì)的全部控制功能。該電子秤可以實(shí)現(xiàn)基本的稱重功能（稱重范圍為0～5Kg，重量誤差不大于±0.005Kg）,并擴(kuò)展了時鐘、溫度檢測和語音報(bào)數(shù)的功能，時鐘模塊還可設(shè)置鬧鐘功能。系統(tǒng)在稱量時還具有超量程報(bào)警功能。整個系統(tǒng)結(jié)構(gòu)簡單，使用方便，功能齊全，精度高，具有一定的開發(fā)價(jià)值。

　　

關(guān)鍵詞：單片機(jī)；稱重傳感器；高精度高增益A/D轉(zhuǎn)換器；1602液晶；矩陣鍵盤；DS1302；DS18B20；語音報(bào)數(shù)


 


 


 




ABSTRACT


　　　The design for the control of 51 computers AT89S52 core, to achieve the basic control functions of electronic scales. In the design of systems, to better use AT89S52 the resources, systems expand the electronic calendar clock with temperature detection module, the system can be defined as Least systems, data acquisition, man-machine interactive interface and the system power supply, clock ,the number of temperature measurement and number of languages reported  six parts . Minimum System includes some AT89S52 and classic reset. Data acquisition is achieved by the load cell, signal amplification and A / D conversion components, signal amplification and A / D converter, which consists of specialized high precision 24-bit AD converter chip HX711; Interactive interface for the keyboard input and dot-matrix liquid crystal display, the main use of 4 * 4 matrix keyboard and LCD display 1602 Sun were public, you can easily input data and visual display of data; System power is an external 9V power supply and power supply circuit board designing for the core circuit to provide normal power supply system; Clock module is composed of clock chip DS1302 and the clock circuit; Temperature detection  is achieved mainly by DS18B20; Voice reported that the number of modules can enroll in time for voice and electronic weighing system, the weight, unit price, amount and other audio content, primarily achieved by the SC1010B.Software part applies microcontroller C programming language to realize all the control functions of the design. The electronic weighing scales can realize the basic functions (weighing range of 0 ~ 5Kg, the weight of the error is not greater than ± 0.005Kg), and extended the clock, temperature monitoring and reporting the number of voice features, the module can also set the alarm clock function. The system at weighing has also super-range alarm. The whole system is simple, easy to use, fully functional, high precision, with some development value.

　　　Key words: SCM; load cell; precision high-gain A / D converter; 1602LCD; matrix keyboard; DS1302; DS18B20; Voice Number.


目  錄


第一章  緒  論 1

1.1   引言 1

1.2  選題背景與意義 1

1.3  研究現(xiàn)狀 2

1.3.1 影響因素 2

1.3.2 產(chǎn)品質(zhì)量 2

1.3.3 發(fā)展方向 3

1.3.4 電子秤的智能化 3

第二章 系統(tǒng)方案的設(shè)計(jì) 4

2.1  電子秤的設(shè)計(jì)要求 4

2.1.1 基本要求 4

2.1.2 特色與創(chuàng)新 4

2.2  實(shí)驗(yàn)原理及設(shè)計(jì)基本思路 4

2.2.1系統(tǒng)工作原理 4

2.2.2 系統(tǒng)設(shè)計(jì)基本思路 5

2.3  系統(tǒng)總體設(shè)計(jì)方案比較與論證 5

2.4  單片機(jī)的選型 6

2.5  數(shù)據(jù)采集部分的方案確定 7

2.5.1 傳感器 7

2.5.2 運(yùn)放與A/D轉(zhuǎn)換器部分 10

2.6人機(jī)交互部分 13

2.6.1 鍵盤輸入 13

2.6.2 輸出顯示 13

2.7  系統(tǒng)電源 13

2.8  具體實(shí)施方案簡介 14

第三章 系統(tǒng)設(shè)計(jì)實(shí)現(xiàn) 17

3.1 基于AT89S52的主控電路 17

3.1.2 主控電路 20

3.2數(shù)據(jù)采集與信號處理轉(zhuǎn)換電路 21

3.2.1 數(shù)據(jù)采集采用HL-8型稱重傳感器 21

3.2.2 信號處理轉(zhuǎn)換采用24位A/D 轉(zhuǎn)換器HX711 21

3.3 人機(jī)交互界面 25

3.3.1 鍵盤控制電路 25

3.3.2 液晶顯示電路 26

3.4系統(tǒng)擴(kuò)展與創(chuàng)新部分 30

3.4.1語音報(bào)數(shù) 30

3.4.2時鐘部分 32

3.4.3溫度檢測部分 36

第四章  軟件流程 42

4.1  主程序流程圖 42

4.2  主要中斷程序流程圖 44

第五章  結(jié)  論 ..