單片機(jī)PID控制

1、經(jīng)典 PID 調(diào)節(jié)，恒溫控制。2009-08-11 20:37#include #include #include#include struct PID unsigned int SetPoint; / 設(shè)定目標(biāo) Desired Value unsigned int Proportion; / 比例常數(shù) Proportional Const unsigned int Integral; / 積分常數(shù) Integral Const unsigned int Derivative; / 微分常數(shù) Derivative Const unsigned int LastError; / Error-1

2、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 data 仁 P1A0;sbit clk=P1Ai； sbit plus=P2A0;sbit subs=P2A1； sbit stop=P2A2； sbit output=P3A4； sbit

3、 DQ=P3A3； unsigned char flag,flag_1=0； unsigned char high_time,low_time,count=0；/ 占空比調(diào)節(jié)參數(shù) unsigned char set_temper=35；unsigned char temper； unsigned char i； unsigned char j=0； unsigned int s；/*延時(shí)子程序，延時(shí)時(shí)間以12M晶振為準(zhǔn),延時(shí)時(shí)間為30usX time*/void delay(unsigned char time)unsigned char m，n； for(n=0；ntime；n+) for(

4、m=0；m2；m+)/*寫一位數(shù)據(jù)子程序*/void write_bit(unsigned char bitval)EA=0;DQ=0; /* 拉低 DQ 以開始一個(gè)寫時(shí)序 */ if(bitval=1)_nop_();DQ=1; /* 如要寫 1，則將總線置高 */delay(5); /* 延時(shí) 90us 供 DA18B20 采樣 */DQ=1;/*釋放 DQ 總線 */_nop_();_nop_();EA=1;/* 寫一字節(jié)數(shù)據(jù)子程序*/void write_byte(unsigned char val)unsigned char i;unsigned char temp;EA=0;TR0

5、=0;for(i=0;ii; /*移位操作，將本次要寫的位移到最低位 */ temp=temp&1;write_bit(temp); /* 向總線寫該位 */ delay(7); /* 延時(shí) 120us 后 */ TR0=1;EA=1;/* 讀一位數(shù)據(jù)子程序*/unsigned char read_bit()unsigned char i,value_bit;EA=0;DQ=0;/*拉低 DQ ，開始讀時(shí)序 */_nop_();_nop_();DQ=1; /* 釋放總線 */for(i=0;i2;i+) value_bit=DQ;EA=1;return(value_bit);/* 讀一字節(jié)數(shù)據(jù)

6、子程序*/unsigned char read_byte()unsigned char i,value=0;EA=0;for(i=0;i8;i+)if(read_bit() /* 讀一字節(jié)數(shù)據(jù)，一個(gè)時(shí)序中讀一次，并作移位處理 */ value|=0x01i;delay(4);/*延時(shí) 80us 以完成此次都時(shí)序，之后再讀下一數(shù)據(jù)*/EA=1;return(value);/*復(fù)位子程序* unsigned char reset()unsigned char presence;EA=0;DQ=0; /* 拉低 DQ 總線開始復(fù)位 */ delay(30); /* 保持低電平 480us*/DQ=1

7、; /* 釋放總線 */delay(3);presence=DQ;/* 獲取應(yīng)答信號(hào) */delay(28); /* 延時(shí)以完成整個(gè)時(shí)序 */EA=1;return(presence);/* 返回應(yīng)答信號(hào)，有芯片應(yīng)答返回0,無芯片則返回 1*/* 獲取溫度子程序* void get_temper()unsigned char i,j;doi=reset(); /* 復(fù)位 */while(i!=0); /*1 為無反饋信號(hào) */i=0xcc; /* 發(fā)送設(shè)備定位命令 */ write_byte(i);i=0x44; /* 發(fā)送開始轉(zhuǎn)換命令 */ write_byte(i);delay(180);

8、 /*延時(shí) */doi=reset(); /* 復(fù)位 */while(i!=0);i=0xcc; /* 設(shè)備定位 */ write_byte(i);i=0xbe; /* 讀出緩沖區(qū)內(nèi)容 */ write_byte(i);j=read_byte();i=read_byte();i=(i4;temper=i|j; /* 獲取的溫度放在 temper 中 */ /*=Initialize PID Structure =*/ void PIDInit (struct PID *pp)memset ( pp,0,sizeof(struct PID);/*=PID 計(jì)算部分=*/ unsigned int

9、 PIDCalc( struct PID *pp, unsigned int NextPoint ) unsigned int dError,Error;Error = pp-SetPoint - NextPoint; / 偏差 pp-SumError += Error; / 積分 dError = pp-LastError - pp-PrevError; / 當(dāng)前微分 pp-PrevError = pp-LastError; pp-LastError = Error;return (pp-Proportion * Error / 比例項(xiàng) + pp-Integral * pp-SumEror

10、/ 積分項(xiàng) + pp-Derivative * dError); / 微分項(xiàng) /* 溫度比較處理子程序*/ compare_temper() unsigned char i;if(set_tempertemper) if(set_temper-temper1) high_time=100; low_time=0; else for(i=0;i10;i+) get_temper(); rin = s; / Read Input rout = PIDCalc ( &spid,rin ); / Perform PID Interation if (high_time=100) high_time=(

11、unsigned char)(rout/800);else high_time=100;low_time= (100-high_time);else if(set_temper0) high_time=0; low_time=100;else for(i=0;i10;i+) get_temper();rin = s; / Read Inputrout = PIDCalc ( &spid,rin ); / Perform PID Interation if (high_time100)high_time=(unsigned char)(rout/10000);else high_time=0;l

12、ow_time= (100-high_time);/ else/ /*T0 中斷服務(wù)子程序，用于控制電平的翻轉(zhuǎn) ,40us*100=4ms 周期 */ void serve_T0() interrupt 1 using 1if(+count=(high_time) output=1;else if(count=100)output=0;elsecount=0;TH0=0x2f;TL0=0xe0;/* 串行口中斷服務(wù)程序，用于上位機(jī)通訊 */ 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)