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;
}