CMF Header

 The header block is built up as follows :-

 ─────────┬─────────────────────────────────────────────────────────────────
   Offset │  Usage
 ─────────┼─────────────────────────────────────────────────────────────────
   00-03  │  File ID - 'CTMF'
   04-05  │  File format version, Major version in MSB, minor in LSB
   06-07  │  Offset of instrument block from start of file
   08-09  │  Offset of music block from start of file
   0A-0B  │  Number of timer ticks per beat (quarter note). Default 48
   0C-0D  │  Clock ticks per second. Default 96
   0E-0F  │  Offset of music title from start of file. Null terminated
          │  ASCII string
   10-11  │  Offset of composer name from start of file
   12-13  │  Offset of remarks string from start of file. (Max 32 bytes)
   14-23  │  Channel-in-use table. Indicates which of 16 FM channels are
          │  used. Corresponding byte set to 1 if channel is used
   24-25  │  Number of instruments used
   26-27  │  Music tempo
   28-    │  Title, Composer and Remark strings (if any)
 ─────────┴─────────────────────────────────────────────────────────────────