蓝桥杯单片机第七届省赛

前言

这套题不难，相对于第六套题这一套比较简单了，但是还是有些小细节要抓

题目

在这里插入图片描述

OK，以上就是全部的题目了，这套题目相对来说逻辑比较简单，四个按键，S4控制pwm占空比，S5控制计时时间，S6控制开关，S7控制界面的切换，用到了定时器，按键，数码管，led（代码中未体现），DS18B20温度采集，逻辑相对简单，下面看看代码

代码

main.c

#include <REGX52.H>
#include "intrins.h"
#include <onewire.h>
sbit S7 = P3^0;
sbit S6 = P3^1;
sbit S5 = P3^2;
sbit S4 = P3^3;unsigned char code SMG_duanma[18]=
{0xc0,0xf9,0xa4,0xb0,0x99,0x92,0x82,0xf8,0x80,0x90,0x88,0x80,0xc6,0xc0,0x86,0x8e,0xbf,0xff};void Chushi()//初始化
{P2 = 0XA0;P0 = 0X00;P2 = 0X80;P0 = 0XFF;P2 = 0XC0;P0 = 0XFF;P2 = 0XFF;P0 = 0XFF;
}void HC138(unsigned char n)//138译码器
{switch(n){case 4:P2 = (P2 & 0X1F) | 0X80;break;case 5:P2 = (P2 & 0X1F) | 0Xa0;break;case 6:P2 = (P2 & 0X1F) | 0Xc0;break;case 7:P2 = (P2 & 0X1F) | 0Xe0;break;}
}void display(unsigned int pos,m)//数码管基础显示
{HC138(6);P0 = 0X01 << pos;HC138(7);P0 = SMG_duanma[m];
}void delay(unsigned int t)//延时1ms
{unsigned char data i, j;while(t--){_nop_();_nop_();_nop_();i = 11;j = 190;do{while (--j);} while (--i);		}}
unsigned int temp;
void wendu()//温度采集
{int LSB,MSB;Init_DS18B20();Write_DS18B20(0xcc);Write_DS18B20(0x44);delay(100);Init_DS18B20();Write_DS18B20(0xcc);Write_DS18B20(0xbe);LSB=Read_DS18B20();MSB=Read_DS18B20();Init_DS18B20();temp=MSB;temp=(temp<<8)|LSB;if((temp&0xf800)==0x0000){temp>>=4;temp=temp+(LSB&0x0f)*0.0625;}
}unsigned int count_pwm,count_time;
unsigned int K4 = 1,K5 = 1,K7;unsigned int pwm,time = 60;
void key()//按键控制
{if(S7 == 0){delay(20);if(S7 == 0){K7++;}while(!S7);}if(S6 == 0){delay(20);if(S6 == 0){time = 0;K5 = 1;}while(!S6);}if(S5 == 0){delay(20);if(S5 == 0){K5++;switch(K5){case 1:time = 60;break;case 2:time = 120;break;case 3:time = 0;break;case 4:K5 = 1;break;}	}while(!S5);}if(S4 == 0){delay(20);if(S4 == 0){K4++;}while(!S4);}switch(K4){case 1:pwm = 20;break;case 2:pwm = 30;break;case 3:pwm = 70;break;case 4:K4 = 1;break;
}
}void Timer0_Init(void)		//5毫秒@11.0592MHz
{TMOD &= 0xF0;		//设置定时器模式TMOD |= 0x01;			//设置定时器模式TL0 = 10240/256;		//设置定时初始值TH0 = 10240%256;		//设置定时初始值TF0 = 0;		//清除TF0标志TR0 = 1;		//定时器0开始计时ET0=1;EA=1;
}void Timer0_Isr(void) interrupt 1
{TL0 = 10240/256;		//设置定时初始值TH0 = 10240%256;		//设置定时初始值count_time++;count_pwm++;if(time != 0){if(count_time >= 20){time--;count_time = 0;}else {if(count_pwm < pwm)P3_4 = 1;else if(count_pwm>=pwm&&count_pwm <100)P3_4 = 0;else if(count_pwm >= 100)count_pwm = 0;}}else if(time == 0){P3_4 = 0;}
}
void display_f()//显示模块1 
{display(0,16);delay(1);display(1,K4);delay(1);display(2,16);delay(1);display(3,17);delay(1);display(4,0);delay(1);display(5,time/100);delay(1);display(6,time%100/10);delay(1);display(7,time%10);delay(1);
}void display_wd()//温度显示模块
{		display(0,16);delay(1);display(1,4);delay(1);display(2,16);delay(1);display(3,17);delay(1);display(4,17);delay(1);display(5,temp/10);delay(1);display(6,temp%10);delay(1);display(7,12);delay(1);
}void main()	
{Chushi();Timer0_Init();while(1){	key();wendu();switch(K7){case 0:display_f();break;case 1:display_wd();break;case 2:K7 = 0;break;}}
}

onewire.h

#ifndef _ONEWIRE_H
#define _ONEWIRE_H#include "regx52.h"#define OW_SKIP_ROM 0xcc
#define DS18B20_CONVERT 0x44
#define DS18B20_READ 0xbe//IC引脚定义
sbit DQ = P1^4;//函数声明
void Delay_OneWire(unsigned int t);
void Write_DS18B20(unsigned char dat);
bit Init_DS18B20(void);
unsigned char Read_DS18B20(void);#endif

onewire.c

#include "onewire.h"//单总线延时函数
void Delay_OneWire(unsigned int t)
{while(t--);
}//DS18B20芯片初始化
bit Init_DS18B20(void)
{bit initflag = 0;DQ = 1;Delay_OneWire(120);DQ = 0;Delay_OneWire(800); DQ = 1;Delay_OneWire(100); initflag = DQ;    Delay_OneWire(50);return initflag;
}//通过单总线向DS18B20写一个字节
void Write_DS18B20(unsigned char dat)
{unsigned char i;for(i=0;i<8;i++){DQ = 0;DQ = dat&0x01;Delay_OneWire(50);DQ = 1;dat >>= 1;}Delay_OneWire(50);
}//从DS18B20读取一个字节
unsigned char Read_DS18B20(void)
{unsigned char i;unsigned char dat;for(i=0;i<8;i++){DQ = 0;dat >>= 1;DQ = 1;if(DQ){dat |= 0x80;}	    Delay_OneWire(50);}return dat;
}