HelpPC 2.10 Quick Reference Utility Copyright 1991 David Jurgens

            INT 21,44,D / IOCTL,D - Generic I/O for Block Devices

       AH = 44h
       AL = 0D
       BL = drive number (0=default, 1=A:, 2=B:, 3=C:, ...)
       CH = device type
          = 08 for disk drive  (block device)
       CL = minor function code
          = 40  set device parameters
          = 41  write track on logical device
          = 42  format/verify track on logical drive
          = 47  set access flag  (DOS 4.x)
          = 60  get device parameters
          = 61  read track on logical device
          = 62  verify track on logical drive
          = 67  get access flag  (DOS 4.x)
       DS:DX = pointer to parameter block


       on return
       AX = error code if CF set  (see DOS ERROR CODES)


       - provides device independent primitive control operations
       - implemented from DOS 3.2
       - see IBM DOS Technical Reference Manual for more details

Esc or Alt-X to exit int 21,44,d Home/PgUp/PgDn/End ←↑↓→