anchor.diff:  
     \ For FAT32:
     sectors/fat @ 0= IF data @ 24 + 4c@ bljoin sectors/fat ! THEN
  +  #root-entries @ 0= IF data @ 2c + 4c@ bljoin ELSE 0 THEN fat32-root-cluster !
   
     \ XXX add other FAT32 stuff (offsets 28, 2c, 30)
   
  
positive.code: : read-cluster ( cluster# -- )
    dup bytes/cluster @ * cluster-offset @ + bytes/cluster @ read-data
    read-fat dup #clusters @ >= IF drop 0 THEN next-cluster ! ;
  : read-dir ( cluster# -- )
    ?dup 0= IF root-offset @ #root-entries @ 20 * read-data 0 next-cluster !
    ELSE read-cluster THEN ;
  
  : .time ( x -- )
    base @ >r decimal
  
negative.code: INSTANCE VARIABLE #reserved-sectors
  INSTANCE VARIABLE #fats
  INSTANCE VARIABLE #root-entries
  INSTANCE VARIABLE fat32-root-cluster
  INSTANCE VARIABLE total-#sectors
  INSTANCE VARIABLE media-descriptor
  INSTANCE VARIABLE sectors/fat
  