基于51单片机的毕业论文

程序设计内容

（1）． 密码的设定，在此程序中密码是固定在程序存储器ROM中，假设预设的密码为“12345”共5位密码。

（2）． 密码的输入问题：  由于采用两个按键来完成密码的输入，那么其中一个按键为功能键，另一个按键为数字键。在输入过程中，首先输入密码的长度，接着根据密码的长度输入密码的位数，直到所有长度的密码都已经输入完毕；或者输入确认功能键之后，才能完成密码的输入过程。进入密码的判断比较处理状态并给出相应的处理过程。

（3）．按键禁止功能：初始化时，是允许按键输入密码，当有按键按下并开始进入按键识别状态时，按键禁止功能被激活，但启动的状态在3次密码输入不正确的情况下发生的。

C语言源程序

#include unsigned char code ps[]={1,2,3,4,5};

unsigned char code dispcode[]={0x3f,0x06,0x5b,0x4f,0x66,                               

0x6d,0x7d,0x07,0x7f,0x6f,0x00,0x40};

unsigned char pslen=9; unsigned char templen;

unsigned char digit; unsigned char funcount;

unsigned char digitcount;

unsigned char psbuf[9];

bit cmpflag;

bit hibitflag;

bit errorflag;

bit rightflag;

unsigned int second3;

unsigned int aa;

unsigned int bb;

bit alarmflag;

bit exchangeflag;

unsigned int cc;

unsigned int dd;

bit okflag;

unsigned char oka;

unsigned char okb;

void main(void)

{  

unsigned char i,j;  

P2=dispcode[digitcount];  

TMOD=0x01;  

TH0=(65536-500)/256;  

TL0=(65536-500)%6;  

TR0=1;  

ET0=1;  

EA=1;  

while(1)   

  {      

if(cmpflag==0)        

{          

if(P3_6==0) //function key           

  {              

for(i=10;i>0;i--)              

for(j=248;j>0;j--);      

         if(P3_6==0)                

{                

   if(hibitflag==0)       

              {     

                  funcount++;  

                     if(funcount==pslen+2)

                        {  

                         funcount=0;

                          cmpflag=1;

                         }

                       P1=dispcode[funcount];

                    }

                    else

                      {

                         second3=0;

                      }  

                 while(P3_6==0);

                }

            }

          if(P3_7==0) //digit key

            {

              for(i=10;i>0;i--)

              for(j=248;j>0;j--);

              if(P3_7==0)

                {

                  if(hibitflag==0)

                    {

                      digitcount++; 

                  if(digitcount==10)

                        {

                          digitcount=0;

                        }

                      P2=dispcode[digitcount];

                      if(funcount==1)

                        {

                          pslen=digitcount;                          

templen=pslen;

                        }

                        else if(funcount>1)

                          {  

                           psbuf[funcount-2]=digitcount;

                          }

                    }

                    else

                      {

                        second3=0;

                      }

                  while(P3_7==0);

                }

            }

        }  

       else

          {

            cmpflag=0;

            for(i=0;i

              {  

               if(ps[i]!=psbuf[i])

                  {

                    hibitflag=1;

                    i=pslen;

                    errorflag=1;

                    rightflag=0;

                    cmpflag=0;

                    second3=0;

                    goto a;  

                 }

              }   

          cc=0;  

           errorflag=0;  

           rightflag=1;

            hibitflag=0;

a:   cmpflag=0;

          }

}

}

void t0(void)

interrupt 1 using 0 {   TH0=(65536-500)/256;  

TL0=(65536-500)%6;  

if((errorflag==1) && (rightflag==0))  

{

      bb++;

      if(bb==800)

        {

          bb=0;

          alarmflag=~alarmflag;

        }

      if(alarmflag==1)

        {

          P0_0=~P0_0;

        }

      aa++;

      if(aa==800)

        {

          aa=0;

          P0_1=~P0_1;

        }

      second3++;

      if(second3==6400)

        {

          second3=0;

          hibitflag=0;

          errorflag=0;

          rightflag=0;

          cmpflag=0;

          P0_1=1;  

         alarmflag=0;

          bb=0;  

         aa=0;  

       }

    }

  if((errorflag==0) && (rightflag==1))

    {

      P0_1=0;

      cc++;

      if(cc<1000)

        {

          okflag=1;

        }

        else if(cc<2000)

          {

            okflag=0;

          }

          else

            {

              errorflag=0;

              rightflag=0;

              hibitflag=0;

              cmpflag=0;

              P0_1=1;

              cc=0;  

             oka=0;

              okb=0;

              okflag=0;  

             P0_0=1;  

           }

      if(okflag==1)

        {  

         oka++;  

         if(oka==2)

            {

              oka=0;

              P0_0=~P0_0;

            }

        }

        else

          {

            okb++;

            if(okb==3)

              {

                okb=0;

                P0_0=~P0_0;

              }  

         }

    }

}