FIC a440 服务手册

 

Hardware Functional Overview 

 

 

FIC A440 Series Service Manual                                                                  4-24 

 
 

The S1 sleeping state is a low wake-up latency sleeping state. In this state, no system context is lost (CPU or chip set) and 
hardware maintains all system context. 

The S2 sleeping state is a low wake-up latency sleeping state. This state is similar to the S1 sleeping state except the CPU 
and system cache context is lost (the OS is responsible for maintaining the caches and CPU context). Control starts from 
the processor’s reset vector after the wake-up event. 

S3 Sleeping State: 

The S3 sleeping state is a low wake-up latency sleeping state where all system context is lost except system memory. 
CPU, cache, and chip set context are lost in this state. Hardware maintains memory context and restores some CPU and L2 
configuration context. Control starts from the processor’s reset vector after the wake-up event. 

The S4 sleeping state is the lowest power, longest wake-up latency sleeping state supported by ACPI. In order to reduce 
power to a minimum, it is assumed that the hardware platform has powered off all devices. Platform context is saved in 
disk. 

The S5 state is similar to the S4 state except the OS does not save any context nor enable any devices to wake the system. 
The system is in the “SOFF” off state and requires a complete boot when awakened.  Software uses a different state value 
to distinguish between the S5 state and the S4 state to allow for initial boot operations within the BIOS to distinguish 
whether or not the boot is going to wake from a saved memory image.  

 

From a user-visible level, the system can be thought of as being one of the states in the following diagram: 

BIOS

Routine