Expects: AX    5302H
BX    0000H (power device ID = System BIOS)
Returns: AH    APM error code (if CF=CY) else...
AX:BX Protected mode entry address
CX    protected mode data segment
Info: This function informs the BIOS that you intend to cooperate with
the BIOS in power management while the CPU is in 16-bit protected
mode. (see INT 15H 5301H for related info).

AX:BX On return, this is a real-mode segment:offset address that can be
used as the entry point for accessing APM services while the CPU
is in 16-bit protected mode (see notes).

CX On return, this is a real-mode segment of a data area that APM
will use later on.

Notes: On return, you must prepare selectors in either the LDT or GDT so
that CS and DS will be valid while APM is operating.  See
DPMI API  for info on preparing selectors.

After making this connection (and preparing the selectors), you
can access power management fns while in 16-bit protected mode by
preparing AX (et al.) and issuing a FAR CALL to the address
returned in AX:BX.

See Also: APM API
- -

INT 15H 5302H: Interface Connect (Prot. Mode/16-bit)