#include "PID.h"
#include "Relays.h"
extern u16 tem;
float cold_tem=0;
float red_tem=0;
float ti;
float ki=0.001;
float kd=340;
extern u8 hot_clod_flag;
extern u8 gpio_state;
PID pid;

void PID_Init()
{
  //pid.set_tem=tem;//用户设定温度
	pid.Kp=170;
	pid.t=500;//PID计算周期
  //pid.Ti=5000000;//积分时间
	//pid.Td=1000;//微分时间
	pid.pwmcycle=200;//pwm周期200
	pid.OUT0=1;
	pid.C1ms=0;
}

void PID_Calc()  //pid计算
{
 	float DelEk;//最近两次偏差之差
	
	//float td;
	
	float out;
 	if(pid.C1ms<(pid.t))  //计算周期未到
		{
				return ;
		}
	if(pid.set_tem>pid.now_tem+1)
		{
			//得到当前的偏差值，设置温度大于实际温度，加热，关闭四通阀
			//GPIO_ResetBits(GPIOA,GPIO_Pin_1);//关闭四通阀
			HC595_Send_Byte(gpio_state&=0xFB);//关闭四通阀		&=1111 1011	    0xFB
			hot_clod_flag=2;	
			//pid.Iout=0;
		}	
	if(pid.now_tem>pid.set_tem+1)
		{
			//得到当前的偏差值，设置温度小于实际温度
			//GPIO_SetBits(GPIOA,GPIO_Pin_1);//打开四通阀，制冷
			HC595_Send_Byte(gpio_state|=0x04);//打开四通阀，制冷 |=0000 0100
			hot_clod_flag=1;
			//pid.Iout=0;
		}
		
	if(pid.set_tem>pid.now_tem)
	{
		pid.Ek=pid.set_tem-pid.now_tem;	
	}
	else
	{
		pid.Ek=pid.now_tem-pid.set_tem;	
	}
 	pid.Pout=pid.Kp*pid.Ek;      //比例输出
 
 	pid.SEk+=pid.Ek;        //历史偏差总和
 
 	DelEk=pid.Ek-pid.Ek_1;  //最近两次偏差之差
 
 	//ti=pid.t/pid.Ti;
 	//ki=ti*pid.Kp;
	
   pid.Iout=ki*pid.SEk;  //积分输出

// 	td=pid.Td/pid.t;
// 
// 	kd=pid.Kp*td;
 
   pid.Dout=kd*DelEk;    //微分输出
	if(pid.Dout<0)
	{
		pid.Dout=0-pid.Dout;
	}
	
 	//out= pid.Pout+ pid.Iout+ pid.Dout;
	out= pid.Pout+pid.Iout+ pid.Dout;
 
 	if(out>pid.pwmcycle)
 	{
  		pid.OUT=pid.pwmcycle;
 	}
 	else if(out<=0)
 	{
		pid.OUT=pid.OUT0; 
 	}
 	else 
 	{
  	pid.OUT=out;
 	}
 	pid.Ek_1=pid.Ek;  //更新偏差
 	pid.C1ms=0;
}