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3 global system state definitions, G0/s0 – working, G1 - sleeping – FIC A360 User Manual

Page 77: G2/s5 – soft off, G3 – mechanical off, 4 device power state definitions, Software functional overview

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Software Functional Overview


3-20

FIC A360 Service Manual

Fan

+3VS SUSB#

VT82C686B (ISA I/F Power ), Clock Generator
& Buffer (W137)

+RTCVCCS Nil

VT82C686B (RTC)

3.5.3 Global System State Definitions

Global system states (Gx states) apply to the entire system and are visible to the user.

Following is a list of the system states:

G0/S0 – Working
A computer state where the system dispatches user mode (application) threads and they
execute. In this state, devices (peripherals) are dynamically having their power state changed.
The user will be able to select (through some user interface) various performance/power
characteristics of the system to have the software optimize for performance or battery life.
The system responds to external events in real time. It is not safe to disassemble the machine
in this state.

G1 - Sleeping
A computer state where the computer consumes a small amount of power, user mode threads
are not being executed, and the system “appears” to be off(from an end user’s perspective, the
display is off, etc). Latency for returning to the Working state varies on the wakeup
environment selected prior to entry of this state (for example, should the system context are
saved by the hardware and the rest by system software. It is not safe to disassemble the
machine in this state.

G2/S5 – Soft Off

A computer state where the computer consumes a minimal amount of power. No user mode
or system mode code is running. This state requires a large latency in order to return to the
Working state. The system’s context will not be preserved by the hardware. The system must
be restarted to return to the Working state. It is not safe to disassemble the machine.

G3 – Mechanical Off
A computer state that is entered and left by a mechanical means. It is implied by the entry of
this off state through a mechanical means that the no electrical current is running through the
circuitry and it can be worked on without damaging the hardware or endangering the service
personnel. The OS must be restarted to return to the Working state. No hardware context is
retained. Except for the real time clock, power consumption is zero.

3.5.4 Device Power State Definitions

Device # CPU K+

C0 Power State

-CPU executes instruction

C1 Power State

-CPU is in Auto Halt State

C2 Power State

-CPU is in Stop Clock mode

C3 Power State

-CPU is in Stop Clock mode