/*********************************************************************
*文件名:crc16thr.c   
*功能： 計(jì)算CRC16循環(huán)冗余校驗(yàn)程序，所用方法為查表法2。
**********************************************************************/
#include <reg51.h>                            //單片機(jī)頭文件
#include <ctype.h>                           
#include <string.h>                          
#include <absacc.h>                        
#include <stdlib.h>                          
#include <stdio.h>                         
#include <math.h>                         
#include <Intrins.h>                          
#include <Stdarg.h>                          

#define uchar unsigned char                    //簡(jiǎn)化定義
#define uint unsigned int                     
#define lint unsigned long int                

void timedelay(uint timess);                   //函數(shù)說(shuō)明
void delay1(uint x);                          
uint crc16(uchar *str,uint num);             
uint data arc,crc1;                            //變量定義
uchar data  rbut[8];                         

uint code  crctable[]={                        //CRC計(jì)算用表
         0x0000,0xC0C1,0xC181,0x0140,0xC301,0x03C0,0x0280,0xC241,
         0xC601,0x06C0,0x0780,0xC741,0x0500,0xC5C1,0xC481,0x0440,
         0xCC01,0x0CC0,0x0D80,0xCD41,0x0F00,0xCFC1,0xCE81,0x0E40,
         0x0A00,0xCAC1,0xCB81,0x0B40,0xC901,0x09C0,0x0880,0xC841,
         0xD801,0x18C0,0x1980,0xD941,0x1B00,0xDBC1,0xDA81,0x1A40,
         0x1E00,0xDEC1,0xDF81,0x1F40,0xDD01,0x1DC0,0x1C80,0xDC41,
         0x1400,0xD4C1,0xD581,0x1540,0xD701,0x17C0,0x1680,0xD641,
         0xD201,0x12C0,0x1380,0xD341,0x1100,0xD1C1,0xD081,0x1040,
         0xF001,0x30C0,0x3180,0xF141,0x3300,0xF3C1,0xF281,0x3240,
         0x3600,0xF6C1,0xF781,0x3740,0xF501,0x35C0,0x3480,0xF441,
         0x3C00,0xFCC1,0xFD81,0x3D40,0xFF01,0x3FC0,0x3E80,0xFE41,
         0xFA01,0x3AC0,0x3B80,0xFB41,0x3900,0xF9C1,0xF881,0x3840,
         0x2800,0xE8C1,0xE981,0x2940,0xEB01,0x2BC0,0x2A80,0xEA41,
         0xEE01,0x2EC0,0x2F80,0xEF41,0x2D00,0xEDC1,0xEC81,0x2C40,
         0xE401,0x24C0,0x2580,0xE541,0x2700,0xE7C1,0xE681,0x2640,
         0x2200,0xE2C1,0xE381,0x2340,0xE101,0x21C0,0x2080,0xE041,
         0xA001,0x60C0,0x6180,0xA141,0x6300,0xA3C1,0xA281,0x6240,
         0x6600,0xA6C1,0xA781,0x6740,0xA501,0x65C0,0x6480,0xA441,
         0x6C00,0xACC1,0xAD81,0x6D40,0xAF01,0x6FC0,0x6E80,0xAE41,
         0xAA01,0x6AC0,0x6B80,0xAB41,0x6900,0xA9C1,0xA881,0x6840,
         0x7800,0xB8C1,0xB981,0x7940,0xBB01,0x7BC0,0x7A80,0xBA41,
         0xBE01,0x7EC0,0x7F80,0xBF41,0x7D00,0xBDC1,0xBC81,0x7C40,
         0xB401,0x74C0,0x7580,0xB541,0x7700,0xB7C1,0xB681,0x7640,
         0x7200,0xB2C1,0xB381,0x7340,0xB101,0x71C0,0x7080,0xB041,
         0x5000,0x90C1,0x9181,0x5140,0x9301,0x53C0,0x5280,0x9241,
         0x9601,0x56C0,0x5780,0x9741,0x5500,0x95C1,0x9481,0x5440,
         0x9C01,0x5CC0,0x5D80,0x9D41,0x5F00,0x9FC1,0x9E81,0x5E40,
         0x5A00,0x9AC1,0x9B81,0x5B40,0x9901,0x59C0,0x5880,0x9841,
         0x8801,0x48C0,0x4980,0x8941,0x4B00,0x8BC1,0x8A81,0x4A40,
         0x4E00,0x8EC1,0x8F81,0x4F40,0x8D01,0x4DC0,0x4C80,0x8C41,
         0x4400,0x84C1,0x8581,0x4540,0x8701,0x47C0,0x4680,0x8641,
         0x8201,0x42C0,0x4380,0x8341,0x4100,0x81C1,0x8081,0x4040};

uint crc16(uchar *str,uint num)          //CRC計(jì)算子程序
{
uint i, crc;
crc=0xffff;
for (i=0; i<num ;i++ )
    {
     arc= (str[i] ^ crc) & 0x00ff;
     crc=_irol_(crc,8);                  //整形循環(huán)右移指令
     crc= crc & 0x00ff;
     crc= crc ^ crctable[arc];
     }
   return(crc);
}
void main()                  //主程序
{                            //初始化
      SP   =0xcf;            //堆棧初始化
      rbut[0]=0x01;          //數(shù)據(jù)初始化
      rbut[1]=0x02;         
      rbut[2]=0x03;         
      rbut[3]=0x04;          
      rbut[4]=0x05;         
      rbut[5]=0x06;         
      rbut[6]=0x07;        
      rbut[7]=0x08;         
      crc1=crc16(rbut,8);    //調(diào)用CRC計(jì)算子程序
      while(1);
}