蓝桥杯ds18b20显示小数和整数

Posted 2022-04-05 一心向月

main.c文件

#include "stc15f2k60s2.h"
#include "onewire.h"
typedef unsigned char u8;
typedef unsigned int u16;
u8 code duan[12]=0xc0,0xf9,0xa4,0xb0,0x99,0x92,
				  0x82,0xf8,0x80,0x90,0xff,0xbf;
u16 temp=0;

void delay(u16 i)

	while(i--);


void Chan_hc573(chose)

	switch(chose)
	
		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;
	
	P2 = ( P2 & 0x1f ) | 0x00;


void Smg_display(u8 com,u8 dat)

	P0=0xff;
	Chan_hc573(7);
	P0=0x01<<com;
	Chan_hc573(6);
	P0=dat;
	Chan_hc573(7);


void Close_smg()

	P0=0x00;
	Chan_hc573(6);
	P0=0xff;
	Chan_hc573(7);


void Display_temp()

	Smg_display(0,duan[temp/1000%10]); delay(500);
	Smg_display(1,duan[temp/100%10]+0x80); delay(500);
	Smg_display(2,duan[temp/10%10]); delay(500);
	Smg_display(3,duan[temp%10]); delay(500);
	Smg_display(4,duan[10]); delay(500);
	Smg_display(5,duan[10]); delay(500);
	Smg_display(6,duan[temp/1000%10]); delay(500);
	Smg_display(7,duan[temp/100%10]); delay(500);
	Close_smg();


void Init_system()

	P0=0x00;
	Chan_hc573(5);
	P0=0xff;
	Chan_hc573(4);


void main()

	Init_system();
	while(1)
	
		temp=ds18b20_read();
		Display_temp();
	

显示小数和整数的区别就是
整数：乘0.0625
保留一位小数：乘0.625
保留两位小数：乘6.25
注意我的底层文件是用于STC89C52RC的，所以延迟函数要扩大10~12倍。
ds18b20.c文件

#include "reg52.h"
#include "onewire.h"

sbit DQ = P1^4;  //µ¥×ÜÏß½Ó¿Ú

//µ¥×ÜÏßÑÓʱº¯Êý
void Delay_OneWire(unsigned int t)  //STC89C52RC

	t *= 12;
	while(t--);


//ͨ¹ýµ¥×ÜÏßÏòDS18B20дһ¸ö×Ö½Ú
void Write_DS18B20(unsigned char dat)

	unsigned char i;
	for(i=0;i<8;i++)
	
		DQ = 0;
		DQ = dat&0x01;
		Delay_OneWire(5);
		DQ = 1;
		dat >>= 1;
	
	Delay_OneWire(5);


//´ÓDS18B20¶ÁÈ¡Ò»¸ö×Ö½Ú
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(5);
	
	return dat;


//DS18B20É豸³õʼ»¯
bit init_ds18b20(void)

  	bit initflag = 0;
  	
  	DQ = 1;
  	Delay_OneWire(12);
  	DQ = 0;
  	Delay_OneWire(80);
  	DQ = 1;
  	Delay_OneWire(10); 
    initflag = DQ;     
  	Delay_OneWire(5);
  
  	return initflag;


float ds18b20_read()

	unsigned char low,hig;
	unsigned int temp;
	init_ds18b20();
	Write_DS18B20(0xcc);
	Write_DS18B20(0x44);
	Delay_OneWire(400);
	
	init_ds18b20();
	Write_DS18B20(0xcc);
	Write_DS18B20(0xbe);
	low=Read_DS18B20();
	hig=Read_DS18B20();
	temp=(hig<<8)|low;
	temp=temp*6.25;
	return temp;

ds18b20.h头文件

#ifndef __ONEWIRE_H
#define __ONEWIRE_H

float ds18b20_read();

#endif