taglinefilesource code
track_shift972drivers/block/floppy.cint count,head_shift,track_shift,total_shift;
track_shift977drivers/block/floppy.ctrack_shift = 2 * head_shift + 1; 
track_shift980drivers/block/floppy.c((track_shift * track + head_shift * head) % floppy->sect);