EEPW论坛

#include "stm32f10x.h"    
#include "stm32_eval.h"    
#include <stdio.h>    
volatile int flag;    
                                                      //板子已将PC12脚接到18B20    
#define Set_B20()    GPIO_SetBits(GPIOC, GPIO_Pin_12)    //关上PC12    
#define Reset_B20()  GPIO_ResetBits(GPIOC, GPIO_Pin_12)   //打开PC12    
#define Read_B20()   GPIO_ReadInputDataBit(GPIOC,GPIO_Pin_12)   //读PC12    
unsigned char Error_Flag=0;    
unsigned char zf=0;      
    
/*延时函数 微秒*/      
void delay_us(u32 n)       
{       
    u8 j;       
    while(n--)       
    for(j=0;j<10;j++);       
}       
/*延时函数 毫秒*/      
void  delay_ms(u32 n)       
{       
   while(n--)       
    delay_us(1000);       
}    
    
void SysTick_Configuration(void)    
{    
    /*==========此次作业的部分===========*/    
  if (SysTick_Config(48000))                //SysTick配置。48000/48ms=1ms    
    /*===================================*/    
  {     
    while (1);    
  }      
  NVIC_SetPriority(SysTick_IRQn, 0x0);                       //SysTick中断优先级    
}    
    
GPIO_InitTypeDef   GPIO_InitStructure;    
USART_InitTypeDef USART_InitStructure;    
USART_ClockInitTypeDef USART_ClockInitStructure;    
    
void RCC_Configuration(void)    
{    
  RCC_DeInit();    
        
  RCC_HSICmd(ENABLE);    
  while(RCC_GetFlagStatus(RCC_FLAG_HSIRDY) == RESET);    
      
  RCC_SYSCLKConfig(RCC_SYSCLKSource_HSI);    
      
  RCC_HSEConfig(RCC_HSE_OFF);    
  RCC_LSEConfig(RCC_LSE_OFF);    
    /*==========此次作业的部分===========*/    
  RCC_PLLConfig(RCC_PLLSource_HSI_Div2,RCC_PLLMul_6);     //  PLLMul_X就是X的倍数，即8*6=48HMz    
    /*===================================*/    
  RCC_PLLCmd(ENABLE);    
  while(RCC_GetFlagStatus(RCC_FLAG_PLLRDY) == RESET);    
  RCC_ADCCLKConfig(RCC_PCLK2_Div4);    
  RCC_PCLK2Config(RCC_HCLK_Div1);    
  RCC_PCLK1Config(RCC_HCLK_Div2);    
  RCC_HCLKConfig(RCC_SYSCLK_Div1);    
  RCC_SYSCLKConfig(RCC_SYSCLKSource_PLLCLK);    
  while(RCC_GetSYSCLKSource() != 0x08);     
//  SystemInit();    
        
    RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOD|RCC_APB2Periph_AFIO, ENABLE);    
  GPIO_PinRemapConfig(GPIO_Remap_SWJ_JTAGDisable,ENABLE);//disable JTAG    
  RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOD|RCC_APB2Periph_AFIO, ENABLE);    
  GPIO_PinRemapConfig(GPIO_Remap_SWJ_JTAGDisable,ENABLE);//disable JTAG    
  GPIO_InitStructure.GPIO_Pin = GPIO_Pin_2;    
  GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;    
  GPIO_InitStructure.GPIO_Mode = GPIO_Mode_Out_PP;    
  GPIO_Init(GPIOD, &GPIO_InitStructure);    
    GPIO_ResetBits(GPIOD,GPIO_Pin_2);    
    RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOC|RCC_APB2Periph_AFIO, ENABLE);    
  GPIO_PinRemapConfig(GPIO_Remap_SWJ_JTAGDisable,ENABLE);//disable JTAG    
  GPIO_InitStructure.GPIO_Pin = GPIO_Pin_0|GPIO_Pin_1|GPIO_Pin_2|GPIO_Pin_3|GPIO_Pin_4|GPIO_Pin_5|GPIO_Pin_6|GPIO_Pin_7;    
  GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;    
  GPIO_InitStructure.GPIO_Mode = GPIO_Mode_Out_PP;    
  GPIO_Init(GPIOC, &GPIO_InitStructure);    
    GPIO_SetBits(GPIOC,GPIO_Pin_0|GPIO_Pin_1|GPIO_Pin_2|GPIO_Pin_3|GPIO_Pin_4|GPIO_Pin_5|GPIO_Pin_6|GPIO_Pin_7);    
    RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM2, ENABLE);    
}     
    
void USART_int(long BaudRate)    
{    
      RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA|RCC_APB2Periph_USART1,ENABLE);    
    GPIO_InitStructure.GPIO_Pin = GPIO_Pin_9;    
    GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;    
    GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;     
    GPIO_Init(GPIOA, &GPIO_InitStructure);    
    /* PA10 USART1_Rx  */    
    GPIO_InitStructure.GPIO_Pin = GPIO_Pin_10;    
    GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IN_FLOATING;    
    GPIO_Init(GPIOA, &GPIO_InitStructure);    
    
        USART_InitStructure.USART_BaudRate = BaudRate;//??????    
        USART_InitStructure.USART_WordLength = USART_WordLength_8b;//???????8bit    
        USART_InitStructure.USART_StopBits = USART_StopBits_1;//????1    
        USART_InitStructure.USART_Parity = USART_Parity_No;//????    
        USART_InitStructure.USART_HardwareFlowControl = USART_HardwareFlowControl_None;//??????none    
        USART_InitStructure.USART_Mode = USART_Mode_Rx | USART_Mode_Tx;//??????????    
        USART_ClockInitStructure.USART_Clock = USART_Clock_Disable;         
        USART_ClockInitStructure.USART_CPOL = USART_CPOL_Low;          
        USART_ClockInitStructure.USART_CPHA = USART_CPHA_2Edge;          
        USART_ClockInitStructure.USART_LastBit = USART_LastBit_Disable;    
        USART_ClockInit(USART1, &USART_ClockInitStructure);    
        USART_Init(USART1, &USART_InitStructure);    
        USART_Cmd(USART1, ENABLE);    
        USART_ITConfig(USART1, USART_IT_RXNE, ENABLE);    
        USART_Cmd(USART1, ENABLE);    
}    
    
void delay_18b20(u32 nus)  //18B20时序要求严格精确，为18B20写的延时函数    
{    
    u16 i;                               //这个函数写的貌似是1us    
    while(nus--)             //nus每减一次，i减12次    
        for(i=12;i>0;i--);    
}    
    
void Init18B20(void)    
{    
   u8 aa=0;    
   u8 count =0;    
     RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOC, ENABLE);  //打开PC时钟    
   GPIO_InitStructure.GPIO_Pin = GPIO_Pin_12;         //选中管脚12    
   GPIO_InitStructure.GPIO_Mode = GPIO_Mode_Out_OD;   //开漏输出    
   GPIO_Init(GPIOC, &GPIO_InitStructure);    
   Set_B20() ;         //拉高    
   delay_18b20(1);    
        
     //一、复位：至少480us的低电平信号，当18b20接收到此信号后会回发芯片一个存在脉冲    
   Reset_B20();        //拉低    
   delay_18b20(480);    
        
     //二、存在脉冲：将数据单总线拉高，接收存在脉冲，通信双方达成基本协议，双方开始数据通信    
   Set_B20();     //拉高    
   delay_18b20(480);    
    
    count=0;    
    aa=Read_B20();   //aa为读得的温度、    
        
/*=====我觉得下面这几句用来统计18B20出现错误的次数，次数到99次的时候报错======*/    
    while(!aa && count<100)   //如果温度值和count数都大于100时    
   {    
    aa=Read_B20();           //再次读温度值    
      count++;                 //发生错误了，数值+1    
   }    
         
   if(count>=99)             //如果发生错误的次数大于99次，那么报错，标志位为1    
        Error_Flag=1;    
     else    
          Error_Flag=0;          //报错次数未达到99次，正常工作      
}    
                             //读一个字节    
unsigned char Read18B20(void)//读18b20里的数据，由于是单数据总线，需要一位一位地读    
{      
unsigned char i=0;    
unsigned char date=0;    
u8 tempp;    
   for(i=8;i>0;i--)//循环8次    
   {    
    
   Reset_B20();   //拉低读数    
   date>>=1;      //右移一位    
   delay_18b20(1);    
   Set_B20();      //拉高    
   delay_18b20(1);    
   tempp=Read_B20();  // tempp为读得的温度    
   if(tempp)    
        date|=0x80;        
        delay_18b20(60);    
    }    
    return(date);    
}    
    
void Write18B20(unsigned char date)   //写一个字节    
{    
    unsigned char i=0;    
    for (i=8; i>0; i--)    
    {    
        Reset_B20();     
        delay_18b20(1);             
        if(date & 0x01)             
        {       
            Set_B20();    
        }    
        else    
        {   Reset_B20();}    
        delay_18b20(60);    
        date>>=1;          
        Set_B20();    
        delay_18b20(1);             
    }    
    delay_18b20(15);    
}    
    
 float Read_T()//    
{       
    unsigned char TUp,TDown;    
    unsigned char fTemp;    
    u8 TT=0;    
    float Temp = 0;    
    Init18B20();    
    Write18B20(0xcc);    // 跳过读取序列号    
    Write18B20(0x44);   //    
    Init18B20();    
    Write18B20(0xcc);   //    
    Write18B20(0xbe);   //      
    TDown = Read18B20();    //低8位    
    TUp = Read18B20();      //高8位       
    if(TUp>0x7f)          
    {    
        TDown=~TDown;      
        TUp=~TUp+1;     
        TUp/=8;              
        zf=1;             
    }    
    else    
    zf=0;         
    fTemp=TDown&0x0f;           
    TUp<<=4;    
    TDown>>=4;    
    TT=TUp|TDown;    
    Temp=TT+(float)fTemp/16;            
    return(Temp);    
}    
                                     
int main(void)    
{    
    int i;    
    unsigned char ID1[8];     //定义一个用于18b20id读取和存放的数组    
  RCC_Configuration();    
  USART_int(115200);    
    SysTick_Configuration();    
        
/*==========此次作业的部分===========*/    
  Init18B20 ();        //初始化DS18B20    
    Write18B20(0x33);     //写入“读取序列号”命令     
  delay_18b20 (15);     
      for(i=0;i<8;i++)    
  {    
        ID1[i]=Read18B20();   //读取18b20发回的64位地址    
  }    
/*===================================*/    
        
    printf(" config done...\r\n");    
    delay_ms(1000);    
        
    while(1)    
    {    
    /*==========此次作业的部分===========*/    
        if(flag == 300){         //300us读一次id    
              printf("The id is:");    
                for(i=0;i<8;i++)            
          {         
                printf("%u",ID1[i]);        
                    if(i==7){printf("\r\n");    }    
        }     
      }    
    /*===================================*/    
                
        if(flag == 500){         //500us读一次温度    
            printf("The Temperature is:%f\r\n",Read_T());    
      }    
    }    
}    
    
#ifdef  USE_FULL_ASSERT    
    
void assert_failed(uint8_t* file, uint32_t line)    
{     
  while (1)    
  {    
  }    
}    
    
#endif    
    
#ifdef __GNUC__    
    
  #define PUTCHAR_PROTOTYPE int __io_putchar(int ch)    
#else    
  #define PUTCHAR_PROTOTYPE int fputc(int ch, FILE *f)    
#endif /* __GNUC__ */    
    
PUTCHAR_PROTOTYPE    
{    
  USART_SendData(EVAL_COM1, (uint8_t) ch);    
    
  /* Loop until the end of transmission */    
  while (USART_GetFlagStatus(EVAL_COM1, USART_FLAG_TC) == RESET)    
  {}    
    
  return ch;    
}    
    
#ifdef  USE_FULL_ASSERT    
    
void assert_failed(uint8_t* file, uint32_t line)    
{     
  while (1)    
  {    
  }    
}    
    
#endif