sub format {
  return [
           [ID           => [10, 'C[10]', '%02X%02X%02X%02X%02X%02X%02X%02X%02X%02X']],
           [MajorVersion => [1,  'C',     '%u']],
           [MinorVersion => [1,  'C',     '%u']],
           [SubVersion   => [1,  'C',     '%u']],
         ];
}