Function 0Eh (14)        Select Default Drive

Sets the default drive and returns the number of logical drives in the
system.

On entry:      AH         0Eh
DL         Drive number (0=A, 1=B, etc.)

Returns:       AL         Number of logical drives in system

                                                                          

Notes:         The floppy disk on a single floppy system is counted
as two logical drives, A: and B:.

DOS 3 and later versions report a minimum of 5
logical drives, unless the CONFIG.SYS file contains
a LASTDRIVE statement.

To determine the number of physical floppy drives on
the system, use Interrupt 11h (17). To determine the
number of physical hard drives, use Interrupt 13h,
Function 8.

See also: INT 11h
See also: INT 13h, 08h

0Eh (14) Select Default Drive