功能介绍：
0.本系统采用STC89C52作为单片机
1.采用LCD1602液晶显示当前时间和检测重量
2.按键可更改时间和设置超重报警阈值
3.采用HEX711和称重支架传感器获取物体重量信息，传入给单片机后再处理，一旦超重后，蜂鸣器报警
4.时钟芯片采用DS1302
原理图：
PCB：
主程序：
#include <reg52.h>#include "main.h"enum MODE_DF{NORMAL, SET_ALARM}dispMode;bit setFlag = 0;unsigned char setIndex=0;unsigned int alarmWeight = 5000;unsigned char alarmWeightBuf;unsigned long initialWeight = 0; //单位gfloat objectWeight = 0; //单位gbit dispFlag; //液晶刷新标志void main(){dispMode = NORMAL;// 定时器初始化Timer0_Init();DS1302_Init();// 开机显示LCD_Init();LCD_DispStr(0, 0, "Electronic Scale");LCD_DispStr(0, 1, "is initializing!");DelayS(2);initialWeight = HX711_GetInitialWeight();LCD_Clear();while(1){if (dispFlag == 1 && setFlag == 0){dispFlag = 0;DS1302_ReadTime();if (dispMode == NORMAL){DispWeight();DispTime(setIndex);}else if (dispMode == SET_ALARM){DispAlarm();}} KeyProcess();}}void DispWeight(){unsigned char dispRow[16];static unsigned char i=0;if (i == 5) //计算5次测量的平均值{objectWeight = objectWeight / 5 - initialWeight;if (objectWeight < 0){objectWeight = 0;}objectWeight = (objectWeight * 10 / GAPVALUE);if (objectWeight > alarmWeight){BUZZER = 0;}else{BUZZER = 1;}sprintf(dispRow, "Weight: %6.3fkg", objectWeight / 1000);LCD_DispStr(0, 1, dispRow);i = 0;objectWeight = 0;}else{TR0 = 0;objectWeight = objectWeight + HX711_Read();TR0 = 1;i++;}}void DispTime(unsigned char setIndex){unsigned char dispRow[16];switch (timeBufDec[7]){case 0: sprintf(dispRow, "%02d/%02d 7 %02d:%02d:%02d", (int)timeBufDec[2], (int)timeBufDec[3], (int)timeBufDec[4], (int)timeBufDec[5], (int)timeBufDec[6]); break;case 1: sprintf(dispRow, "%02d/%02d 7 %02d:%02d:%02d", (int)timeBufDec[2], (int)timeBufDec[3], (int)timeBufDec[4], (int)timeBufDec[5], (int)timeBufDec[6]); break;case 2: sprintf(dispRow, "%02d/%02d 1 %02d:%02d:%02d", (int)timeBufDec[2], (int)timeBufDec[3], (int)timeBufDec[4], (int)timeBufDec[5], (int)timeBufDec[6]); break;case 3: sprintf(dispRow, "%02d/%02d 2 %02d:%02d:%02d", (int)timeBufDec[2], (int)timeBufDec[3], (int)timeBufDec[4], (int)timeBufDec[5], (int)timeBufDec[6]); break;case 4: sprintf(dispRow, "%02d/%02d 3 %02d:%02d:%02d", (int)timeBufDec[2], (int)timeBufDec[3], (int)timeBufDec[4], (int)timeBufDec[5], (int)timeBufDec[6]); break;case 5: sprintf(dispRow, "%02d/%02d 4 %02d:%02d:%02d", (int)timeBufDec[2], (int)timeBufDec[3], (int)timeBufDec[4], (int)timeBufDec[5], (int)timeBufDec[6]); break;case 6: sprintf(dispRow, "%02d/%02d 5 %02d:%02d:%02d", (int)timeBufDec[2], (int)timeBufDec[3], (int)timeBufDec[4], (int)timeBufDec[5], (int)timeBufDec[6]); break;case 7: sprintf(dispRow, "%02d/%02d 6 %02d:%02d:%02d", (int)timeBufDec[2], (int)timeBufDec[3], (int)timeBufDec[4], (int)timeBufDec[5], (int)timeBufDec[6]); break;default: ;}LCD_DispStr(0, 0, dispRow);switch (setIndex){case 1: LCD_LocateXY(1 , 0); break;case 2: LCD_LocateXY(4 , 0); break;case 3: LCD_LocateXY(6 , 0); break;case 4: LCD_LocateXY(9 , 0); break;case 5: LCD_LocateXY(12, 0); break;case 6: LCD_LocateXY(15, 0); break;default: ;}}void DispAlarm(){unsigned char dispRow[16];sprintf(dispRow, "Alarm : %6.3fkg", (float)alarmWeight / 1000);LCD_DispStr(0, 0, dispRow);}void KeyProcess(){if (!KEY_UP) //按键加{DelayMs(180);if (!KEY_UP){if (dispMode == NORMAL && setFlag == 1){switch (setIndex){case 1:{timeBufDec[2]++;if (timeBufDec[2] >= 13){timeBufDec[2] = 1;}break;}case 2:{timeBufDec[3]++;if (timeBufDec[3] >= YDay(timeBufDec[1], timeBufDec[2]) + 1){timeBufDec[3] = 1;}break;}case 3:{timeBufDec[7]++;if (timeBufDec[7] > 7){timeBufDec[7] = 1;}break;}case 4:{timeBufDec[4]++;if (timeBufDec[4] >= 24){timeBufDec[4] = 0;}break;}case 5:{timeBufDec[5]++;if (timeBufDec[5] >= 60){timeBufDec[5] = 0;}break;}case 6:{timeBufDec[6]++;if (timeBufDec[6] >= 60){timeBufDec[6] = 0;}break;}default:;}DispTime(setIndex);} if (dispMode == SET_ALARM){alarmWeight = alarmWeight + 10;if (alarmWeight > 5000){alarmWeight = 5000;}}}//while (!KEY_UP);}if (!KEY_DOWN) //按键减{DelayMs(180);if (!KEY_DOWN){if (dispMode == NORMAL && setFlag == 1){switch (setIndex){case 1:{timeBufDec[2]--;if (timeBufDec[2] < 1){timeBufDec[2] = 12;}break;}case 2:{timeBufDec[3]--;if (timeBufDec[3] < 1){timeBufDec[3] = YDay(timeBufDec[1], timeBufDec[2]);}break;}case 3:{timeBufDec[7]--;if (timeBufDec[7] < 1){timeBufDec[7] = 7;}break;}case 4:{if (timeBufDec[4] == 0){timeBufDec[4] = 24;}timeBufDec[4]--;break;}case 5:{if (timeBufDec[5] == 0){timeBufDec[5] = 60;}timeBufDec[5]--;break;}case 6:{if (timeBufDec[6] == 0){timeBufDec[6] = 60;}timeBufDec[6]--;break;}default:;}DispTime(setIndex);} if (dispMode == SET_ALARM){alarmWeight = alarmWeight - 10;if (alarmWeight <= 0){alarmWeight = 0;}}}//while (!KEY_DOWN);}if (!KEY_SET){DelayMs(20);if (!KEY_SET){if (dispMode == NORMAL){if (setFlag == 0){setFlag = 1; //进入时间设置setIndex = 1;}else{setIndex++;if (setIndex >= 7){setFlag = 0; //退出时间设置setIndex = 0;}}DispTime(setIndex);}}
仿真演示视频：
/video/BV16U4y1m7bc/
实物演示视频：
/video/BV13v4y1A7Wj/
