此系統(tǒng)是基于PID的單片機(jī)溫度控制系統(tǒng)，我在網(wǎng)上搜到一段完整的程序，并按他的程序做出了相應(yīng)的proteus硬件仿真，但是并沒(méi)有達(dá)到預(yù)期的效果.待提高。程序如下：#include＜reg51.h>#include＜intrins.h>#include＜math.h>#include＜string.h>structPID{unsignedintSetPoint;//設(shè)定目標(biāo)DesiredValueunsignedintProportion;//比例常數(shù)ProportionalConstunsignedintIntegral;//積分常數(shù)IntegralConstunsignedintDerivative;//微分常數(shù)DerivativeConstunsignedintLastError;//Error[-1]unsignedintPrevError;//Error[-2]unsignedintSumError;//SumsofErrors};structPIDspid;//PIDControlStructureunsignedintrout;//PIDResponse(Output)unsignedintrin;//PIDFeedback(Input)sbitdata1=P1^0;sbitclk=P1^1;sbitplus=P2^0;sbitsubs=P2^1;sbitstop=P2^2;sbitoutput=P3^4;sbitDQ=P3^3;unsignedcharflag,flag_1=0;unsignedcharhigh_time,low_time,count=0;//占空比調(diào)節(jié)參數(shù)unsignedcharset_temper=35;unsignedchartemper;unsignedchari;unsignedcharj=0;unsignedints;/***********************************************************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30us×time***********************************************************/voiddelay(unsignedchartime){unsignedcharm,n;for(n=0;n＜time;n++)for(m=0;m＜2;m++){}}/***********************************************************寫(xiě)一位數(shù)據(jù)子程序***********************************************************/voidwrite_bit(unsignedcharbitval){EA=0;DQ=0;/*拉低DQ以開(kāi)始一個(gè)寫(xiě)時(shí)序*/if(bitval==1){_nop_();DQ=1;/*如要寫(xiě)1，則將總線(xiàn)置高*/}delay(5);/*延時(shí)90us供DA18B20采樣*/DQ=1;/*釋放DQ總線(xiàn)*/_nop_();_nop_();EA=1;}/***********************************************************寫(xiě)一字節(jié)數(shù)據(jù)子程序***********************************************************/voidwrite_byte(unsignedcharval){unsignedchari;unsignedchartemp;EA=0;TR0=0;for(i=0;i＜8;i++)/*寫(xiě)一字節(jié)數(shù)據(jù)，一次寫(xiě)一位*/{temp=val>>i;/*移位操作，將本次要寫(xiě)的位移到最低位*/temp=temp&1;write_bit(temp);/*向總線(xiàn)寫(xiě)該位*/}delay(7);/*延時(shí)120us后*///TR0=1;EA=1;}/***********************************************************讀一位數(shù)據(jù)子程序***********************************************************/unsignedcharread_bit(){unsignedchari,value_bit;EA=0;DQ=0;/*拉低DQ，開(kāi)始讀時(shí)序*/_nop_();_nop_();DQ=1;/*釋放總線(xiàn)*/for(i=0;i＜2;i++){}value_bit=DQ;EA=1;return(value_bit);}/***********************************************************讀一字節(jié)數(shù)據(jù)子程序***********************************************************/unsignedcharread_byte(){unsignedchari,value=0;EA=0;for(i=0;i＜8;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|=0x01＜＜i;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***********************************************************/unsignedcharreset(){unsignedcharpresence;EA=0;DQ=0;/*拉低DQ總線(xiàn)開(kāi)始復(fù)位*/delay(30);/*保持低電平480us*/DQ=1;/*釋放總線(xiàn)*/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(wú)芯片則返回1*/}/***********************************************************獲取溫度子程序***********************************************************/voidget_temper(){unsignedchari,j;do{i=reset();/*復(fù)位*/}while(i!=0);/*1為無(wú)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(kāi)始轉(zhuǎn)換命令*/write_byte(i);delay(180);/*延時(shí)*/do{i=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=(i＜＜4)&0x7f;s=(unsignedint)(j&0x0f);s=(s*100)/16;j=j>>4;temper=i|j;/*獲取的溫度放在temper中*/}/*====================================================================================================InitializePIDStructure=====================================================================================================*/voidPIDInit(structPID*pp){memset(pp,0,sizeof(structPID));}/*====================================================================================================PID計(jì)算部分=====================================================================================================*/unsignedintPIDCalc(structPID*pp,unsignedintNextPoint){unsignedintdError,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->SumError//積分項(xiàng)+pp->Derivative*dError);//微分項(xiàng)}/***********************************************************溫度比較處理子程序***********************************************************/compare_temper(){unsignedchari;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;//ReadInputrout=PIDCalc(&spid,rin);//PerformPIDInteration}if(high_time＜=100){high_time=(unsignedchar)(rout/800);}else{high_time=100;}low_time=(100-high_time);}}elseif(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;//ReadInputrout=PIDCalc(&spid,rin);//PerformPIDInteration}if(high_time＜100){high_time=(unsignedchar)(rout/10000);}else{high_time=0;}low_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******************************************************/voidserve_T0()interrupt1using1{if(++count＜=(high_time))output=1;elseif(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******************************************************/voidserve_sio()interrupt4using2{/*EA=0;RI=0;i=SBUF;if(i==2){while(RI==0){}RI=0;set_temper=SBUF;SBUF=0x02;while(TI==0){}TI=0;}elseif(i==3){TI=0;SBUF=temper;while(TI==0){}TI=0;}EA=1;*/}voiddisp_1(unsignedchardisp_num1[6]){unsignedcharn,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;elsedata1=0;_nop_();clk=1;_nop_();}}}/*****************************************************顯示子程序功能：將占空比溫度轉(zhuǎn)化為單個(gè)字符，顯示占空比和測(cè)得到的溫度******************************************************/voiddisplay(){unsignedcharcodenumber[]={0xfc,0x60,0xda,0xf2,0x66,0xb6,0xbe,0xe0,0xfe,0xf6};unsignedchardisp_num[6];unsignedintk,k1;k=high_time;k=k%1000;k1=k/100;if(k1==0)disp_num[0]=0;elsedisp_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(){unsignedcharz;unsignedchara,b,flag_2=1,count1=0;unsignedcharphil[]={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);//InitializeStructurespid.Proportion=10;//SetPIDCoefficientsspid.Integral=8;spid.Derivative=6;spid.SetPoint=100;//SetPIDSetpointwhile(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;}}elseif(subs==0){for(a=0;a＜5;a++)for(b=0;a＜102;b++){}if(subs==0){set_temper--;flag=0;}}elseif(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;}}