crc.vhd

用汇编语言编写得TD中使用得CC和CRC代码

entity crc is
  port (CRC_inPortmes:in integer32@8;
        CRC_inPortsl:in integer32@8;
        CRC_outPort:out integer32@8);
end entity crc;
  
architecture C of crc is
begin STAN2 "-O2"   
   CODE

int main() 
{
   unsigned int store_data,ai,li,temp;            
   unsigned int judge,buffer_state,res_state,buffer_state1,res_state1;
   integer32 out;                   
   integer32 sigling;
   
  while(1)
  {
    sigling = getCRC_inPortsl();
    ai = sigling;                   // ai is the length of the messages bits 
    sigling = getCRC_inPortsl();
    li = sigling;  		    //  li is the length of the CRC.
    
    if(ai==0)                      
    {
	for(temp=0;temp<li;temp++)
	{
	    out=0;			// if ai==0, then all the CRC bits equal to zero.
            putCRC_outPort(out);
	}
    }
    else
    {   
       
        buffer_state=0; buffer_state1=0;
	if(li==8)  res_state=435;
	if(li==12) res_state=7683;
	if(li==16) res_state=2065; 
	if(li==24) { res_state=3; res_state1=396;}
	for(temp=0;temp<ai;temp++)
	{
		out=getCRC_inPortmes();
		putCRC_outPort(out);
		store_data=(int)out;
		judge=(store_data)^(buffer_state&1); 
		if(judge==1)
		{
			buffer_state^=res_state;
			buffer_state>>=1;
			if(li==16)
				buffer_state|=32768;
			if(li==24)
			{	
				buffer_state1^=res_state1;
				if((buffer_state1&1)==1)
			         	{buffer_state|=32768;}
				buffer_state1>>=1;
			}

		}
		else
		{
			buffer_state>>=1;
			if(li==24)
			{	
				if((buffer_state1&1)==1)
			    	       { buffer_state|=32768;}
				buffer_state1>>=1;
			}
		}
			
	}          
		
	if(li<17)	
	for(temp=0;temp<li;temp++)            
	{
		 out=(buffer_state>>temp)&1;
		 putCRC_outPort(out);
	}
	else
	{
	     for(temp=0;temp<16;temp++)
  		 {out=(buffer_state>>temp)&1;
		  putCRC_outPort(out);}
	     for(temp=0;temp<8;temp++)
		 {out=(buffer_state1>>temp)&1;
		  putCRC_outPort(out);}	
	}
      
       
    }         // the end of "else"

 }           // the end of "while"
  return 0;
}
  ENDCODE;
end crc;