Bitfields for flags describing drive: Bit(s) Description ) 0 fixed media 1 door lock ("changeline") supported 2 current BPB locked 3 all sectors in a track are the same size 4 physical drive has multiple logical units 5 current logical drive for shared physical drive 6 disk change detected 7 device parameters were changed (set DASD before formatting) (see #01560 at INT 21/AX=440Dh"DOS 3.2+") 8 disk reformatted (BPB of current media was changed) 9 access flag (fixed media only, disables reads and writes) (see #01566 at INT 21/AX=440Dh"DOS 3.2+")