code: func (t *ElapsedTime) UnmarshalBinary(p []byte) error {
  	b := buffer.New(p)
  	if b.Len() != 2 {
  		return io.ErrUnexpectedEOF
  	}
  
  	// Time is reported in hundredths of seconds, so we convert it to a more
  	// manageable milliseconds
  	*t = ElapsedTime(time.Duration(b.Read16()) * 10 * time.Millisecond)
  	return nil
  }
docs: // UnmarshalBinary unmarshals a raw byte slice into a ElapsedTime.
  //
  // If the byte slice is not exactly 2 bytes in length, io.ErrUnexpectedEOF is
  // returned.