摘  要

　　　

　　　該設計以51系列單片機AT89S52為控制核心，實現(xiàn)電子秤的基本控制功能。在設計系統(tǒng)時，為了更好利用AT89S52的資源，系統(tǒng)擴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、人機交互界面和系統(tǒng)電源、時鐘、溫度檢測和語言報數(shù)六大部分。最小系統(tǒng)部分主要包括AT89S52和經(jīng)典復位電路；數(shù)據(jù)采集部分由稱重傳感器、信號放大和A/D轉換部分組成，信號放大和A/D轉換部分主要由專用型高精度24位AD轉換芯片HX711實現(xiàn)；人機交互界面為鍵盤輸入和點陣式液晶顯示，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計電路以提供系統(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實現(xiàn)；語音報數(shù)模塊可語音報讀時間和電子秤系統(tǒng)的重量、單價、金額等語音內(nèi)容，主要由SC1010B實現(xiàn)。軟件部分應用單片機C語言進行編程，實現(xiàn)了該設計的全部控制功能。該電子秤可以實現(xiàn)基本的稱重功能（稱重范圍為0～5Kg，重量誤差不大于±0.005Kg）,并擴展了時鐘、溫度檢測和語音報數(shù)的功能，時鐘模塊還可設置鬧鐘功能。系統(tǒng)在稱量時還具有超量程報警功能。整個系統(tǒng)結構簡單，使用方便，功能齊全，精度高，具有一定的開發(fā)價值。

　　

關鍵詞：單片機；稱重傳感器；高精度高增益A/D轉換器；1602液晶；矩陣鍵盤；DS1302；DS18B20；語音報數(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)方案的設計 4

2.1  電子秤的設計要求 4

2.1.1 基本要求 4

2.1.2 特色與創(chuàng)新 4

2.2  實驗原理及設計基本思路 4

2.2.1系統(tǒng)工作原理 4

2.2.2 系統(tǒng)設計基本思路 5

2.3  系統(tǒng)總體設計方案比較與論證 5

2.4  單片機的選型 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 運放與A/D轉換器部分 10

2.6人機交互部分 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  具體實施方案簡介 14

第三章 系統(tǒng)設計實現(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 信號處理轉換采用24位A/D 轉換器HX711 21

3.3 人機交互界面 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)擴展與創(chuàng)新部分 30

3.4.1語音報數(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  論 ..