INT 15 - Advanced Power Management Specification - CONNECT REAL-MODE INTERFACE
AX = 5301h
BX = 0000h (device ID of system BIOS)
Return: CF clear if successful
CF set on error
AH = error code (02h,09h) (see AX=5300h)
SeeAlso: AX=5303h,AX=5304h

See also: 155302

155301BX0000 - Advanced Power Management Specification - CONNECT REAL-MODE INTERFACE