Apm Bios Functions - HP Deskpro EX Technical Reference Manual

Chapter 8 BIOS ROM
Table 8-6. APM BIOS Functions
APM BIOS Function
APM Installation Check
APM Real Mode Interface
Connect
APM Protected Mode 16-bit
APM Protected Mode 32-bit
APM Interface Disconnect
CPU Idle
CPU Busy
Set Power State
Enable/Disable Power
Management
Restore Power-On Defaults
Get Power Status
Get PM Event
Get Power State
Enable/Disable Device PM
APM Driver Version
Engage/Disengage PM
Get Capabilities
Get/Set/Disable Resume
Timer
Enable/Disable Resume on
Ring
Enable/Disable Timer Based
Request
8-20 Compaq Deskpro EX Series of Personal Computers
Table 8-6.

APM BIOS Functions

Description
Allows the O/S to determine if the system's BIOS
supports the APM functionality and if so, which version of
the specification it supports. The APM version number
returned from this call is the highest level of APM
supported by the BIOS.
Establishes the cooperative interface between the O/S and the
BIOS. The BIOS provides OEM-defined power management
functionality before the interface is established. Once the interface
is established, the BIOS and the O/S Driver coordinate power
management activities. The BIOS rejects an interface connect
request if any real or protected mode connection already exists.
Initializes the 16-bit protected mode interface between the O/S and
the BIOS. This interface allows a protected mode caller to invoke
the BIOS functions without first switching into real or virtual-86
mode. This function must be invoked in real mode. This is not
currently used by any O/S.
Iinitializes the 32-bit protected mode interface between the O/S and
the BIOS. This interface allows a protected mode O/S to invoke the
BIOS functions without the need to first switch into real or virtual-86
mode. This function must be invoked in real mode.
Breaks the cooperative connection between the BIOS and the O/S,
and returns control of the power management policy to the BIOS.
Power management parameter values (timer values, enable/disable
settings, etc.) in effect at the time of the disconnect remain in
effect.
The O/S uses this call to tell BIOS that the system is idle.
Informs the BIOS that the O/S has determined that the system is
now busy. The BIOS should restore the CPU clock rate to full
speed.
Sets the system or device specified in the power device ID into the
requested power state.
Enables or disables all APM BIOS automatic power management.
When disabled, the BIOS does not automatically power manage
devices, enter the Standby State, enter the Suspend State, or take
power saving steps in response to CPU Idle calls.
Re-initializes all power-on defaults.
This call returns the system current power status.
Returns the next pending PM event, or indicates if no PM events
are pending.
Returns the device power state when a specific device ID is used.
Enables or disables APM BIOS automatic power management for a
specified device. When disabled, the APM BIOS does not
automatically power manage the device.
The O/S uses this call to indicate its level of APM support to the
BIOS. The BIOS returns the APM connection version number.
Engages or disengages cooperative power management of the
system or device.
Returns the features which this particular APM 1.2 BIOS
implementation supports.
This call gets, sets, or disables the system resume timer.
Enables or disables the system's resume on ring indicator
functionality. It also returns the enabled/disabled status.
Enables or disables the BIOS's generation of global Standby and
global Suspend requests based on inactivity timers.
First Edition - August 2000