in addition to loading RapidLok files, they do a complicated check 
      on certain sync lengths, header lengths, and track to track 
      alignment.
      
      RAPIDLOK FORMAT
      
      Like Commodore DOS, RapidLok formats its tracks by first writing
      a header block, and then a $0255 byte long data block. The method 
      through which RapidLok converts this data into REAL bytes is much 
      too confusing to explain in this overview. The following is how 
      RapidLok would format one track:
      
      1) The Reference Header:
      
      The first header on a RapidLok track is the track reference
      header. It is actually a normal Commodore DOS header for that 
      track, sector 0 in GCR format. It is written with a SYNC LENGTH of 
      $0029 bytes. If RapidLok DOS detects a reference header without the 
      correct sync length, the load will abort.
      
      Example:
      
      SYNC: $0029 Bytes: 52 57 35 29 6B 74 DC B5 = track 19, sector 0
      
      2) The LONG-SYNC RapidLok Header:
      
      The second header on a RapidLok track is actually the header for
      RapidLok sector 0. All RapidLok headers begin with a $75, and 
      contain 7 important bytes that the RapidLok loader needs to detect. 
      These bytes are followed by 3 or 4 GAP BYTES that are written out 
      as #$00's. (Any attempt to read these bytes will return a different 
      byte value each time.)  The RapidLok header block for sector 0 (1st 
      header block) has a SYNC LENGTH of $003C bytes, though. The 
      RapidLok loader will fail if this sync length is not found.
      
      Example:
      
      SYNC: $003C BYTES: 75 93 59 25 D6 ED 7A 4C 00 00 00 00 = sector 0
      
      The remaining headers for sectors 1 through the maximum have SYNC 
      LENGTHS of $0005, and are not checked by the loader.
      
      3) The RapidLok Data block:
      
      Each data block begins with a $6B value and follows the header
      for that particular sector. Each data block contains approximately 
      $0255 bytes of data, which is converted into normal DATA and sent 
      from the drive to the computer. Each data block has a sync-length 
      of $0005 bytes, and is not checked by the loader. Sometimes a 
      RapidLok sector will be blank. The data block will then begin with
      
            K.J. REVEALED TRILOGY    PAGE [88]     (C)1990 K.J.P.B.