crc.c

ASC 信号机控制程序,国内最先进的信号机控制程序

#include <reg51.h>
#include <absacc.h>
sbit   WatchDog = P1^3;       //看门狗
//#define Begin
extern unsigned int comm_state;
unsigned char xdata  RX_BUF[512];
unsigned int xdata  head=0;
unsigned int xdata  tail=0;
unsigned char transparence=0;
unsigned char testbit=0;
unsigned char REVSTATUS=0;
unsigned char xdata checkdata[512];
unsigned short checktemp=0;
unsigned int transparence_valid=0;
unsigned int data_num=4;
unsigned int check_write=0;
unsigned int check_temp=0;
unsigned char beginbit=0;
unsigned char valid_data=0;
unsigned char valid_data_num=0;
unsigned char receive_flag;
unsigned char xdata second_flag;

extern unsigned char xdata h_address;
extern unsigned char xdata l_address;

sbit   watch_dog=P1^3;
void  com_receive_deal();
void check_transparence()
{
   switch(transparence){
      case 0:if(testbit==1){
                  transparence =1;
                  transparence_valid=0;
                            }else {
                            transparence =0;
                            transparence_valid=0;
                                  }
             break;
      case 1:if(testbit==1){
                  transparence =2;
                  transparence_valid=0;
                            }else {
                            transparence =0;
                            transparence_valid=0;
                                  }
             break;
      case 2:if(testbit==1){
                  transparence =3;
                  transparence_valid=0;
                            }else {
                            transparence =0;
                            transparence_valid=0;
                                  }
             break;
      case 3:if(testbit==1){
                  transparence =4;
                  transparence_valid=0;
                            }else {
                            transparence =0;
                            transparence_valid=0;
                                  }
             break;
      case 4:if(testbit==1){
                  transparence =5;
                  transparence_valid=0;
                            }else {
                            transparence =0;
                            transparence_valid=0;
                                  }
             break;
      case 5:if(testbit==0){
                  transparence =0;
                  transparence_valid=1;
                            }else {
                            transparence =6;
                            transparence_valid=1;
                                  }
             break;
      case 6:if(testbit==0){
                  transparence =0;
                  transparence_valid=1;
                  REVSTATUS=0;
                            }else {
                            REVSTATUS=0X55;
                            transparence_valid=0;
                                  }
             break;
      default:break;
           }
}

check_frame()
{
     switch(beginbit){
       case 0:if(testbit==0){
                   beginbit=1;
                   REVSTATUS=0;
                             }else{
                         beginbit=0;
                                   }
              break;
       case 1:if(testbit==1){
                   beginbit=2;
                   REVSTATUS=0;
                             }else{
                         beginbit=1;
                         REVSTATUS=0;
                                   }
              break;
       case 2:if(testbit==1){
                   beginbit=3;
                   REVSTATUS=0;
                             }else{
                         beginbit=1;
                         REVSTATUS=0;
                                   }
              break;
       case 3:if(testbit==1){
                   beginbit=4;
                   REVSTATUS=0;
                             }else{
                         beginbit=1;
                         REVSTATUS=0;
                                   }
              break;
       case 4:if(testbit==1){
                   beginbit=5;
                   REVSTATUS=0;
                             }else{
                         beginbit=1;
                         REVSTATUS=0;
                                   }
              break;
       case 5:if(testbit==1){
                   beginbit=6;
                   REVSTATUS=0;
                             }else{
                         beginbit=1;
                         REVSTATUS=0;
                                   }
              break;
       case 6:if(testbit==1){
                   beginbit=7;
                   REVSTATUS=0;
                             }else{
                         beginbit=1;
                         REVSTATUS=0;
                                   }
              break;
       case 7:if(testbit==0){
                   beginbit=0;
                   REVSTATUS=1;
                             }else{
                         beginbit=0;
                         REVSTATUS=0;
                                   }
              break;
       default:beginbit=0;
               REVSTATUS=0;
               break;
                     }
}
unsigned short cal_crc(unsigned char *ptr,unsigned int len)
{
 unsigned char i;
 unsigned short  crc=0;

 while(len--!=0){
	for(i=0x80;i!=0;i/=2){
		if((crc&0x8000)!=0){
			crc*=2;
			crc^=0x1021;
			               }
		else
		  crc*=2;
	    if((*ptr&i)!=0)
	      crc^=0x1021;
		                }
		ptr++;
	            }
  	return(crc);
}
void crc_main()
{
  unsigned char i;
  unsigned char *p;
 WatchDog =!WatchDog;
 check_write=0;
 check_temp=0;
   /////////////////////////////////////////////////////////////////