INT 15 - Advanced Power Management Specification - SET POWER STATE
AX = 5307h
BX = device ID (see below)
CX = system state ID
0000h ready (not supported for device ID 0001h)
0001h stand-by
0002h suspend
0003h off (not supported for device ID 0001h)
0004h-FFFFh reserved
Return: CF clear if successful
CF set on error
AH = error code (01h,09h,0Ah,60h) (see AX=5300h)
Note:   should not be called from within a hardware interrupt handler to avoid
reentrance problems

Values for device IDs:
0000h  system BIOS
0001h  all devices for which the system BIOS manages power
01xxh  display (01FFh for all attached display devices)
02xxh  secondary storage (02FFh for all attached secondary storage devices)
03xxh  parallel ports (03FFh for all attached parallel ports)
04xxh  serial ports (04FFh for all attached serial ports)
0500h-FFFFh reserved


155307 - Advanced Power Management Specification - SET POWER STATE