//51 温度PID经典算法
#include<reg51.h>
#include<intrins.h>
#include<math.h>
#include<string.h>
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=25
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=0n<timen++)
for(m=0m<2m++){}
}
/***********************************************************
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DA18B20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=0i<8i++) /*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=0i<2i++){}
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=0i<8i++)
{
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<<i
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)//得到小数部分
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)) //全部初始化为0
}
/*====================================================================================================
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->SumError // 积分项
+ pp->Derivative * dError) // 微分项
}
/***********************************************************
温度比较处理子程序
***********************************************************/
void compare_temper()
{
unsigned char i
if(set_temper>temper) //是否设置的温度大于实际温度
{
if(set_temper-temper>1) //设置的温度比实际的温度是否是大于1度
{
high_time=100 //如果是，则全速加热
low_time=0
}
else //如果是在1度范围内，则运行PID计算
{
for(i=0i<10i++)
{
get_temper() //获取温度
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=0i<10i++)
{
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=0n<6n++)
{
// k=disp_num1[n]
for(a=0a<8a++)
{
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
***********************************************************/
void 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 比例常数 Proportional Const
spid.Integral = 8 //积分常数 Integral Const
spid.Derivative =6 //微分常数 Derivative Const
spid.SetPoint = 100// Set PID Setpoint 设定目标 Desired Value
while(1)
{
if(plus==0)
{
EA=0
for(a=0a<5a++)
for(b=0b<102b++){}
if(plus==0)
{
set_temper++
flag=0
}
}
else if(subs==0)
{
for(a=0a<5a++)
for(b=0a<102b++){}
if(subs==0)
{
set_temper--
flag=0
}
}
else if(stop==0)
{
for(a=0a<5a++)
for(b=0b<102b++){}
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=0a<5a++)
for(b=0b<102b++){}
if(stop==0)
disp_1(phil)
// break
}
EA=1
}
}
看你用到什么上，如果是四旋翼，要通过四个翼的方向来判断。如果是单纯的一个pwm的PID闭环系统，比如稳压恒流，电机恒速，那就直接将P+I+D部分输出给PWM就是了。比如MSP430的：CCR1=P+I+D； 这里的CCR1就是430脉宽。PID会自己通过测量到的实际值调整CCR1的值，也就是脉宽。#include <stdio.h>#include <string.h>
#include <unistd.h>
#include <stdlib.h>
#include <sys/types.h>
#include <sys/wait.h>
int main()
{
int pipe_fds[2]
int pid
if(pipe(pipe_fds))
{
fprintf(stderr,"pipe error!\n")
return -1
}
if((pid = fork())<0)
{
fprintf(stderr, "fork error!\n")
return -1
}
if(pid == 0)
{
char buf[20] = {0}
int n,i
close(pipe_fds[1])
read(pipe_fds[0],buf,sizeof(buf))
n=atoi(buf)
for(i=1i<=ni++)
{
if(i%10 == 0)
printf("\n")
printf("%d\t",i)
}
close(pipe_fds[0])
}
else
{
int m
char bf[20] = {0}
close(pipe_fds[0])
printf("the child pid:%d\n",pid)
printf("please input number:")
scanf("%d",&m)
printf("\n")
sprintf(bf,"%d",m)
write(pipe_fds[1],bf,sizeof(bf))
wait(NULL)
printf("child complete!\n")
}
return 0
}
