DEFINE_DEVICE_TYPE:  Decrement
  PORT_LIST( in, out );
  /* Local shared variables. */
  int xxxx;

  DEFINE_THREAD:   start_up
   {
    int value, len;

    while (1)
     {
      RECEIVE( "in", &value, &len );
      value = value - 1;
      SEND( "out", value, 1 );
     }
   }
  END_DEFINE_THREAD.

END_DEFINE_DEVICE_TYPE.