INT 15H 5300H: Installation Check
Expects: AX 5300H
BX 0000H (power device ID = System BIOS)
Returns: AH 86H = APM not installed (and CF=CY)
APM major version number, in BCD (if CF=NC)
AL APM minor version number, in BCD
BX 504dH (BH='P' and BL='M')
CX flags: bit 0: 1 = 16-bit protected-mode interface supported
bit 1: 1 = 32-bit protected-mode interface supported
bit 2: 1 = CPU Idle calls slow the CPU clock speed
bit 3: 1 = BIOS power management is disabled
Info: This function checks to see whether the BIOS supports APM and
obtains the version of the APM spec that is supported.
AX the version number is in BCD; e.g., 0312H is version 3.12
BX See INT 15H 5305H (CPU Busy) for info on bit 3.
See Also: APM API