ds1820-lcd.c

AVR单片机编程

/* 
  本程序为采用mega8 和18b20的温度采集程序 
  选用mega8内部8M RC震荡，18b20 数据线接pd6,数据线和vcc间接一4.7k上拉电阻 
*/ 

#include <iom8v.h> //和单片机类型相对应的头文件，选择Atmega8做实验； 
#include <macros.h> 
#define uchar unsigned char 
#define uint unsigned int 
#define osccal 0xAC//内部RC校正常数
#define WR      0B00100000//时钟线 
#define DATA    0B00001000//数据线 
#define CS      0b00010000//片选线 
#define word_long   8 
 
unsigned char seg_table[ ] ={0XFB,0X60,0XC7,0XE5,0X6C,0XAD,0XAF,0XE0,0XEF,0XED};
unsigned char count,con; 
/*****************************************************************/ 
   /*LCD系统命令（可选)*/ 
const char TAB_REST[10]={0b00000001,/*打开系统振荡器命令*/ 
                         0b00000011,/*打开LCD 偏压发生器命令*/ 
                         0b00000101,/*WDT 溢出标志输出失效命令*/ 
                         0b00000110,/*时基输出使能命令*/ 
                         0b00011000,/*系统时钟源片内RC振荡器命令*/ 
                         0b00101001,/*LCD1/3偏压选项4个公共口命令*/ 
                         0b01000000,/*声音频率4KHz命令*/ 
                         0b00001001,/*打开声音输出命令*/ 
                         0b10100000,/*时基/WDT 时钟输出1Hz命令*/ 
                         0b10001000};/*使/IRQ 输出有效命令*/                                                                         
void send_data(unsigned char data_bus,unsigned char loop);
void lcd_display(void);
void delay_us(uint time);
void init_1820(void); 
void write_1820(uchar x); 
uchar read_1820(void); 
 
void delay_us(uint x)  //1.5us左右 
{ 
  do
       x--; 
  while (x>1);
} 

void init_1820() 
{ 
     DDRD|=(1<<6);    
     PORTD&=~(1<<6); 
     delay_us(500);   
     PORTD|=(1<<6); 
     DDRD&=~(1<<6); 
     delay_us(30);    
    while(PIND&(1<<6)) 
    { 
     ; 
    } 
    delay_us(200);   
} 

void write_1820(uchar cmd) 
{    
   uchar i,j; 
   DDRD|=(1<<6); 
 for(j=0;j<=7;j++) 
    { 
    	 i=cmd&0x01;
       if (i==0x01)
    	 {   	   	 
           PORTD&=~(1<<6); 
           delay_us(10);    
           PORTD|=(1<<6);
           delay_us(100);  
         } 
     else
         {
           PORTD&=~(1<<6); 
           delay_us(100);    
           PORTD|=(1<<6);
           delay_us(10);
         } 
      cmd=cmd>>1;
     }
}

uchar read_1820() 
{     
   uchar temp=0,tmp,i; 
   for(i=0;i<8;i++) 
     { 
      DDRD|=(1<<6);
      PORTD&=~(1<<6); 
      delay_us(3);       
      PORTD|=(1<<6);     
      DDRD&=~(1<<6); 
      delay_us(10); 
      tmp=(PIND&(1<<6));    
      if(tmp!=0x00)  temp|=0x80; 
      if(i<7) temp=temp>>1;        
      delay_us(100);    
      //DDRD|=(1<<6); 
      //delay_us(5);
    } 
   return (temp); 
}  
 	 
void ht1621_int(void) 
{ 
  uchar t; 
  PORTB &=~CS;
  PORTB |=WR; 
  asm("nop");
  PORTB &=~WR;
  asm("nop");
  send_data(0b10000000,3);/*送3位命令模式代码100*/ 
  for(t=0;t<=9;t++) 
  { 
   send_data(TAB_REST[t],9);/*送9位命令代码*/  
  } 
  PORTB |=CS; 
  PORTB |=WR;
  PORTB |=DATA; 
} 

void lcd_display() 
 { 
  uchar temp[3];
  uchar t;
  PORTB &=~CS;
  PORTB |=WR; 
  asm("nop");
  PORTB &=~WR;
  asm("nop");
  send_data(0b10100000,3);    /*送3位WRITE 模式命令代码101*/ 
  send_data(0,6);             /*送6位首地址00h*/ 
  //temp[2] =count / 100;							//转换百位值		
  temp[3] =(count-temp[2]*100)/10; 
  temp[6] =(count-temp[2]*100-temp[3]*10)%10;
  //temp[3] =0;  
  temp[7] =con;
   for(t=0;t<16;t++) 
    { 
	if (t<3)  send_data(0,word_long);
	//if (t==2) send_data(seg_table[temp[t]],word_long);
	if (t==3) send_data(seg_table[temp[t]],word_long);
	if (t==4) send_data(0,word_long);
	if (t==5) send_data(0,word_long);
	if (t==6) send_data(seg_table[temp[t]]|0x10,word_long);
	if (t==7) send_data(seg_table[temp[t]],word_long);
	if (t>7) send_data(0,word_long);
      } 	 
  PORTB |=CS; 
  PORTB |=WR; 
  PORTB |=DATA;
 } 
 
void send_data(uchar data_bus,uchar loop) 
 { 
  for(;loop!=0;loop--) 
  { 
   delay_us(5); 
   PORTB &=~WR; 
   if((data_bus&0b10000000)==0) 
    { 
     PORTB &=~DATA; 
    } 
   else 
    { 
     PORTB |=DATA; 
    } 
   data_bus=data_bus<<1; 
   PORTB |=WR; 
  }    
 }
 
void main(void) //主函数 
{ 
	
  DDRB =0XFF; 
  PORTB =0XFF;   
  DDRD=0XFF; 
  PORTD=0XFF;
  OSCCAL=0xac;//系统时钟校准，不同的芯片和不同的频率，    
  ht1621_int();
  //lcd_display();   
  delay_us(100);
  while(1) 
   { 
      uchar i,temh,teml; 
      uint temp;
      init_1820();        //复位18b20 
      write_1820(0xcc);   // 发出转换命令 
      write_1820(0x44); 
      for(i=0;i<200;i++)   //每次转换需要延时400ms以上 
      delay_us(2000);  
      init_1820(); 
      write_1820(0xcc);   //发出读命令 
      write_1820(0xbe); 
      teml=read_1820();  //读数据 
      temh=read_1820();
	  temp=temh<<8;
      temp=((temp+teml) & 0x7ff) ;
      count=((temp>>4)& 0x7f);
	  con=(teml&0xf0)? 5:0;  
      lcd_display();        //显示温度       
    } 
}