Int 67 Fn 5C  - Lim Ems 4.0 - Prepare Expanded Memory Hardware For Warm B  [m]

   AH = 5Ch

Return: AH = status (see #3334)

Note:  when MS-DOS v6.xx EMM386 is loaded and the keyboard driver supports
     INT 15/AH=4Fh (keyboard intercept) calls, the system may hang
     instead of booting if this function is called just prior to a jump
     to F000h:FFF0h

(Table 3334)
Values for EMS function status:
 00h   successful
 80h   internal error
 81h   hardware malfunction
 84h   undefined function requested