Broadcom BCM5722 - Figure 75: APM Architecture

BCM5722 Programmer’s Guide
10/15/07
Broadcom Corporation
Page 519 APM Document 5722-PG101-R
Figure 75: APM Architecture
APM manages system power consumption using six managed states (see Figure 76):
• Full On—System is running at full power. Devices do not implement power conservation measures.
• APM Enabled—System is running under full power. The system does implement power management.
• APM Standby—System running at reduced power. Power managed devices reduce their power consumption to low-
power. The processor and/or system clock may be slowed.
• APM Suspend—System is at maximum power conservation. The microprocessor stops clock. CPU core is in low-power
mode. Power managed devices are turned off.
• Hibernation—System is completely switched off. Before shutdown, memory is stored to non-volatile storage (i.e., hard
drive). Memory modules are turned off.
• Off—No power to system.
APM-Aware Device Drivers APM-Aware Device Drivers APM-Aware Device Drivers...
O/S APM Driver
APM BIOS
APM interface Protected Mode APM interface Real Mode
Operating System
BIOS
APM Device
System