51单片机-温度控制-PID算法-DS18B20-C语言

#include

#include

#include

struct PID {

unsigned int SetPoint; // 设定目标 Desired Value

unsigned int Proportion; // 比例常数 Proportional Const

unsigned int Integral; // 积分常数 Integral Const

unsigned int Derivative; // 微分常数 Derivative Const

unsigned int LastError; // Error[-1]

unsigned int PrevError; // Error[-2]

unsigned int SumError; // Sums of Errors

};

struct PID spid; // PID Control Structure

unsigned int rout; // PID Response (Output)

unsigned int rin; // PID Feedback (Input)

sbit data1=P1^0;

sbit clk=P1^1;

sbit plus=P2^0;

sbit subs=P2^1;

sbit stop=P2^2;

sbit output=P3^4;

sbit DQ=P3^3;

unsigned char flag,flag_1=0;

unsigned char high_time,low_time,count=0;//占空比调节参数

unsigned char set_temper=35;  

unsigned char temper;       

unsigned char i;

unsigned char j=0;

unsigned int s;

/***********************************************************

延时子程序,延时时间以12M晶振为准,延时时间为30us×time

***********************************************************/

void delay(unsigned char time)

  {

   unsigned char m,n;

     for(n=0;n

       for(m=0;m<2;m++){}

  }

/***********************************************************

写一位数据子程序

***********************************************************/

void write_bit(unsigned char bitval)

  {

    EA=0;

      DQ=0;  /*拉低DQ以开始一个写时序*/

    if(bitval==1)

       {

        _nop_();

        DQ=1;   /*如要写1，则将总线置高*/

        }

      delay(5);   /*延时90us供DS18B20采样*/

    DQ=1;  /*释放DQ总线*/

    _nop_();

    _nop_();

   EA=1;

   }

/***********************************************************

写一字节数据子程序

***********************************************************/

void write_byte(unsigned char val)

{

  unsigned char i;

  unsigned char temp;

  EA=0;

  TR0=0;

  for(i=0;i<8;i++)  /*写一字节数据，一次写一位*/

      {

       temp=val>>i;  /*移位操作，将本次要写的位移到最低位*/

       temp=temp&1;

       write_bit(temp);  /*向总线写该位*/

       }

   delay(7);   /*延时120us后*/

// TR0=1;

  EA=1;

  }

/***********************************************************

读一位数据子程序

***********************************************************/

unsigned char read_bit()

{

  unsigned char i,value_bit;

  EA=0;

  DQ=0;   /*拉低DQ，开始读时序*/

  _nop_();

  _nop_();

  DQ=1;   /*释放总线*/

  for(i=0;i<2;i++){}

  value_bit=DQ;

  EA=1;

  return(value_bit);

  }

/***********************************************************

读一字节数据子程序

***********************************************************/

unsigned char read_byte()

  {

   unsigned char i,value=0;

   EA=0;

   for(i=0;i<8;i++)

      {

       if(read_bit())  /*读一字节数据，一个时序中读一次，并作移位处理*/

         value|=0x01<

       delay(4);  /*延时80us以完成此次都时序，之后再读下一数据*/

       }

   EA=1;

   return(value);

  }

/***********************************************************

复位子程序

***********************************************************/

unsigned char reset()

  {

   unsigned char presence;

   EA=0;

   DQ=0;   /*拉低DQ总线开始复位*/

   delay(30);   /*保持低电平480us*/

   DQ=1;   /*释放总线*/

   delay(3);  

   presence=DQ;   /*获取应答信号*/

   delay(28);   /*延时以完成整个时序*/

   EA=1;

   return(presence);  /*返回应答信号，有芯片应答返回0,无芯片则返回1*/

  }

/***********************************************************

获取温度子程序

***********************************************************/

void get_temper()

{

  unsigned char i,j;

  do

  {

    i=reset();  /*复位*/

  }while(i!=0);  /*1为无反馈信号*/

  i=0xcc;  /*发送设备定位命令*/

  write_byte(i);

  i=0x44;  /*发送开始转换命令*/

  write_byte(i);

  delay(180);  /*延时*/

  do

  {

  i=reset();  /*复位*/

  }while(i!=0); 

  i=0xcc;  /*设备定位*/

  write_byte(i);

  i=0xbe;  /*读出缓冲区内容*/

  write_byte(i);

  j=read_byte();

  i=read_byte();  

  i=(i<<4)&0x7f;

  s=(unsigned int)(j&0x0f);

  s=(s*100)/16;

  j=j>>4;

  temper=i|j;                                      /*获取的温度放在temper中

*/

  }

/*=========================================================================

===========================

Initialize PID Structure

===========================================================================

==========================*/

void PIDInit (struct PID *pp)

{

memset ( pp,0,sizeof(struct PID));

}

/*=========================================================================

===========================

PID计算部分

===========================================================================

==========================*/

unsigned int PIDCalc( struct PID *pp, unsigned int NextPoint )

{

unsigned int dError,Error;

Error = pp->SetPoint - NextPoint; // 偏差

pp->SumError += Error; // 积分

dError = pp->LastError - pp->PrevError; // 当前微分

pp->PrevError = pp->LastError;

pp->LastError = Error;

return (pp->Proportion * Error // 比例项

+ pp->Integral * pp->SumEror // 积分项

+ pp->Derivative * dError); // 微分项

}

/***********************************************************

温度比较处理子程序

***********************************************************/

compare_temper()

{

  unsigned char i;

     if(set_temper>temper)

         {

          if(set_temper-temper>1)  

             {

              high_time=100;

              low_time=0;

             }

          else

             {

               for(i=0;i<10;i++)

                 {  get_temper();

                    rin = s; // Read Input

                    rout = PIDCalc ( &spid,rin ); // Perform PID Interation

                 }

               if (high_time<=100)

                 high_time=(unsigned char)(rout/800);

               else

                 high_time=100;

               low_time= (100-high_time);

             }

         }

      else if(set_temper<=temper)

             {

               if(temper-set_temper>0)

                 {

                   high_time=0;

                   low_time=100;

                 }

               else

               {

                 for(i=0;i<10;i++)

                 {  get_temper();

                    rin = s; // Read Input

                    rout = PIDCalc ( &spid,rin ); // Perform PID Interation

                 }

                 if (high_time<100)

                   high_time=(unsigned char)(rout/10000);

                 else

                   high_time=0;

                 low_time= (100-high_time);

               }

             }

     //  else

     //      {}

    }

/*****************************************************

T0中断服务子程序，用于控制电平的翻转 ,40us*100=4ms周期

******************************************************/

void serve_T0() interrupt 1 using 1

  {

   if(++count<=(high_time))

     output=1;

   else if(count<=100)

     {

      output=0;

      }

   else

      count=0;

   TH0=0x2f;

   TL0=0xe0;

   }

/*****************************************************

串行口中断服务程序，用于上位机通讯

******************************************************/

void serve_sio() interrupt 4 using 2

  {

/*   EA=0;

   RI=0; 

   i=SBUF;

   if(i==2)

      {

       while(RI==0){} 

       RI=0;

       set_temper=SBUF; 

       SBUF=0x02; 

       while(TI==0){}

       TI=0;

       }

    else if(i==3) 

       {

        TI=0;

       SBUF=temper;

        while(TI==0){}

        TI=0;

        }

     EA=1;   */

   }

void disp_1(unsigned char disp_num1[6])

{

     unsigned char n,a,m;

     for(n=0;n<6;n++)

      {

     //  k=disp_num1[n];

       for(a=0;a<8;a++)

         {

          clk=0;

           m=(disp_num1[n]&1);

            disp_num1[n]=disp_num1[n]>>1;

          if(m==1)

             data1=1;

          else

             data1=0;

          _nop_();

          clk=1;

          _nop_();

          }

       }

}

/*****************************************************

显示子程序

功能：将占空比温度转化为单个字符，显示占空比和测得到的温度

******************************************************/

void display()

{

unsigned char code number[]=

{0xfc,0x60,0xda,0xf2,0x66,0xb6,0xbe,0xe0,0xfe,0xf6};

unsigned char disp_num[6];

unsigned int k,k1;

k=high_time;

k=k%1000;

k1=k/100;

if(k1==0)

    disp_num[0]=0;

else

    disp_num[0]=0x60;

k=k%100;

disp_num[1]=number[k/10];

disp_num[2]=number[k%10];

k=temper;

k=k%100;

disp_num[3]=number[k/10];

disp_num[4]=number[k%10]+1;

disp_num[5]=number[s/10];

disp_1(disp_num);

}

/***********************************************************

主程序

***********************************************************/

main()

{

  unsigned char z;

  unsigned char a,b,flag_2=1,count1=0;

  unsigned char phil[]={2,0xce,0x6e,0x60,0x1c,2};;

  TMOD=0x21;  

  TH0=0x2f;  

  TL0=0x40;

  SCON=0x50;  

  PCON=0x00;            

  TH1=0xfd;  

  TL1=0xfd;

  PS=1;          

  EA=1;   

  EX1=0;  

  ET0=1;  

  ES=1;   

  TR0=1; 

  TR1=1;

  high_time=50;                

  low_time=50;

  PIDInit ( &spid ); // Initialize Structure

  spid.Proportion = 10; // Set PID Coefficients

  spid.Integral = 8;

  spid.Derivative =6;

  spid.SetPoint = 100; // Set PID Setpoint

  while(1)

       {

           if(plus==0)

             {

              EA=0;

              for(a=0;a<5;a++)

                for(b=0;b<102;b++){} 

                if(plus==0)

                  {

                  set_temper++;

                  flag=0;

                  }

              }

            else if(subs==0)

              {

               for(a=0;a<5;a++)

                  for(b=0;a<102;b++){} 

                  if(subs==0)

                  {

                    set_temper--;

                    flag=0;

                   }

               }

            else if(stop==0)

               {

                for(a=0;a<5;a++)

                   for(b=0;b<102;b++){} 

                   if(stop==0)

                   {

                   flag=0;         

                   break;

                   }

             EA=1;

             }

      get_temper();

      b=temper;

      if(flag_2==1)

         a=b;

      if((abs(a-b))>5)

        temper=a;

      else

        temper=b;

      a=temper;

      flag_2=0;

      if(++count1>30)

         {

          display();

          count1=0;

          }

      compare_temper();  

       }

    TR0=0;

    z=1;

while(1)

      {

       EA=0;

       if(stop==0)

        {

         for(a=0;a<5;a++)

           for(b=0;b<102;b++){}

         if(stop==0)

           disp_1(phil);

        //        break;

           }

      EA=1;

         }

}