/* CRC16
  -------------------------------------
  This  macro  transmits a message from
  the send dialog and appends two bytes 
  with CRC at the end
*/
var CRCValue;

main()
{
  var i,s;
  for(i = 0; i < get_message_count(); i=i+1) 
  {
   sleep(get_delay_before_message());
   inner_cycle(i);
   CRCValue = not(CRCValue);
   putx(CRCValue&0xFF);
   putx(shr(CRCValue,8)&0xFF);
   flush();
  }
}

inner_cycle(i)
{
   var j,t;
   CRCValue=0xFFFF;	
   for(j=0; j<get_message_length(i);j=j+1)
   {
    t = get_message_at(i,j);
    putx(t);
    add2crc(t);
   }
}

add2crc(b)
{
	var acc,i,a,c;
	acc = b;
	for (i = 0; i < 8; i=i+1) {
		a = acc^CRCValue;
		c = a & 0x0001;
		if (c==0x0001) 
		{
		 CRCValue = CRCValue ^ 0x0810;
		} 
		CRCValue = shr(CRCValue,1);
		if (c==0x0001) 
		{
		 CRCValue = CRCValue | 0x8000;
		} 
		c = acc & 0x0001;
		acc = shr (acc,1);
		if (c==0x0001) 
		{
		 acc = acc | 0x8000;
		} 
	};
}