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Aptiva - 2140/2142 Power management

Applicable to: World-Wide

Document Objectives:

• Describe Intrepid/Defiant power management function.
• Describe potential field problems with power management design and implementation.

New Concepts:

• Intrepid/Defiant power management attempts to follow the industry standard implementation and no longer uses Rapid Resume.

• Previously used features of Wake Up from off are now used only by Home Director option.

System Information

Online Help:

• Under Access Aptiva Discover & Help: What is...
• Topics can be found under Energy Saving Features in What is...

Hardware Requirements:
- No longer requires a unique Wake Up on Ring cable for the modem.

Software Requirements:
- Operating system Advanced Power Management (APM) support is required for full power management function. This is enabled by default in Windows.

Specifications:

Introduction

This document describes the power management function for Intrepid and Defiant systems. The document is divided into the following sections:

System Power States
APM Capabilities
Activity Detection
APM Wake Up Functions
Power State Transitions
Home Director Support
Non-APM Power Management

System Power States

The defined system power states for Intrepid/Defiant systems are as follows:

OFF: the CPU, power supply, fan, etc. are not running and the power LED is blank. If the monitor is powered on, its LED is amber.

SUSPEND: the CPU and internal fan are halted, but the power supply and its fan are still running. The hard disk(s) are spun down and the monitor screen is blank. The system power LED is illuminated (green) and the monitor LED blinks between amber and green.

STANDBY: the CPU, internal fan, and power supply are still running. The hard disk(s) are spun down and the monitor screen is blank. The LEDs are the same as in SUSPEND, but the hard disk LED may periodically be illuminated if the hard disk(s) are accessed while still in STANDBY.

NOTE: Only Suspend is presented to the customer as a low power state because it is difficult for most people to distinguish between Standby and Suspend.

ON: all parts of the system, including the hard disk(s) and monitor, are fully operating. The system and monitor LEDs are green.

APM Capabilities

Intrepid/Defiant BIOS supports the following APM capabilities, which are reported through the APM Get Capabilities (10H) function call:

System can enter global Standby state. Indicates BIOS will post Standby and Standby Resume events.

NOTE: BIOS only supports Standby as a backup to Suspend, or as a non-APM lower power state. If a driver or application rejects a Suspend request in Windows, the APM driver may issue a Standby call to BIOS but will not broadcast Standby messages.

System can enter global Suspend state. Indicates BIOS will post Suspend and Suspend Resume events.

• Resume timer will wake up from Suspend.
• Resume on ring indicator will wake up from Suspend.

The following APM capabilities are NOT supported:

• Resume timer will wake up from Standby.
• Resume on ring indicator will wake up from Standby.
• PCMCIA ring indicator will wake up from Standby.
• PCMCIA ring indicator will wake up from Suspend.

The BIOS implementation of Suspend under APM is as follows:

1. If the Suspend Timer expires, BIOS returns a Suspend Request to the operating system. If the operator initiates the Suspend via the Start Menu or the Suspend button the keyboard, BIOS does not issue a Suspend Request.

2. The operating system APM driver issues a Set Power State function call for BIOS to put the system into Suspend.

3. BIOS puts the graphics controller in a low power state via a VESA DPMS function call. The priority of low power states is Standby, Suspend, and Off. BIOS will issue the INT 10H call to VESA BIOS based on the first supported low power graphics mode.

4. BIOS issues a Standby Immediate command to all ATA drives (i.e. hard disks) in the system.

5. BIOS turns off the internal fan via a command to the on-board power management processor.

6. BIOS arms the chip set to generate an SMI based on hardware activity for a Wake Up on Alarm (if enabled), a Wake Up on Ring (if enabled), and for the activity checking options in Setup.

7. BIOS disables interrupts and halts the CPU.

8. Upon hardware activity, an SMI occurs and BIOS restarts the internal fan and returns the graphics controller to the On state. BIOS does NOT bring the ATA drives out of Standby mode, but allows the drive(s) to spin up automatically when they need to process other ATA commands.

9. At the next Get Event function call, BIOS returns a Suspend Resume notification to the APM driver.

Activity Detection

Intrepid/Defiant BIOS detects activity based on the capabilities of the chip set for each planar. The chip sets use combinations of I/O ports, interrupts, and other signals to detect activity. Activity detection provides two functions: keeping the system from entering SUSPEND or STANDBY, and bringing the system back to ON from SUSPEND or STANDBY. Normally I/O port activity prevents the system from entering SUSPEND or STANDBY and interrupt activity is required to bring the system back to ON.

Spear Planar (Pentium II processor)

The Setup Utility activity checking options include the following devices for Spear. The chip set detection information is also listed.

• Keyboard and Mouse: IRQs 1 and 12
• Disk Drives 1 and 2: I/O ports 1F0-1F7H, 3F6H; PDDACK#
• Disk Drives 3 and 4: I/O ports 170-177H, 376H; SDDACK#
• Diskette Drive(s): I/O ports 3F0-3F5H, 3F7H; DACK2#
• Serial Port: I/O ports 2F8-2FFH, 3E8-3EFH, or 2E8-2EFH (active setting); Ring Indicate signal
• Parallel Port: I/O ports 378-37FH, 778-77AH; 278-27FH, 678-67AH; or 3BC-3BFH, 7BC-7BEH (active setting)
• Modem: I/O ports 3F8-3FFH; IRQ 4

Wake Up on Alarm activity shall be generated by the Real-time Clock Alarm interrupt (IRQ 8). Wake Up on Ring activity shall be generated by the modem interrupt (IRQ 4), which is wired to the LID status signal on the chip set. Serial port Wake Up (for Home Director) shall be generated by the serial port Ring Indicate signal, which is tied to the RI# status signal on the chip set.

Sword Planar (Pentium MMX processor)

The Setup Utility activity checking options include the following devices for Sword. The chip set detection information is also listed.

• Keyboard and Mouse: I/O ports 60H, 64H; IRQs 1 and 12
• Disk Drives 1 and 2: I/O ports 1F0-1F7H, 3F6H; IRQ 14
• Disk Drives 3 and 4: I/O ports 170-177H, 376H; IRQ 15
• Diskette Drive(s): I/O ports 3F0-3F3H; IRQ 6
• Serial Port: I/O ports 2F8-2FFH and 2E8-2EFH or 3F8-3FFH and 3E8-3EFH; IRQ 3 or 4 (the active IRQ)
• Parallel Port: I/O ports 278-27FH, 378-37FH, and 3BC-3BEH; IRQ 7 (the active IRQ)
• Modem: I/O ports 3F8-3FFH and 3E8-3EFH; IRQ 4

Wake Up on Alarm activity shall be generated by the Real-time Clock Alarm interrupt (IRQ 8). Wake Up on Ring activity shall be generated by the modem interrupt (IRQ 4). Serial port Wake Up (for Home Director) shall be generated by the active serial port interrupt (normally IRQ 3).

APM Wake Up Functions

Intrepid/Defiant APM BIOS supports Wake Up on Ring ("Wake up the computer when the phone rings" in Windows) and Wake Up on Alarm ("Resume from Suspend" in Scheduler) under APM. (There are also other Wake Up events reserved for Home Director described in "Home Director Support".)

Wake Up on Ring

The system behaves as follows when Wake Up on Ring is enabled and the system is in the SUSPEND state:

• The modem detects the ring indication and generates an interrupt.
• As a result of the modem interrupt, the system comes out of SUSPEND and returns to ON.
• The telephony application answers the call and receives a fax or records a voice message. After the call completes, the telephony application turns on the system "message waiting" indicator.

Conversely the system behaves as follows when Wake Up on Ring is disabled and the system is in the SUSPEND state:

• The modem ignores the ring indication.
• There is no hardware activity to bring the system out of SUSPEND.

Wake Up on Alarm

The system behaves as follows when Wake Up on Alarm is enabled and the system is in the SUSPEND state:

• The Real-time Clock generates an interrupt at the specified time.
• As a result of the RTC interrupt, the system comes out of SUSPEND and returns to ON.
• The scheduled events are able to execute.

Power State Transitions

OFF to ON

The system will transit from OFF to ON under the following conditions:

• When power is first provided to the planar or power supply. (If the CMOS information indicates the system was last OFF, power will be removed early in POST.)
• When the power supply and planar are already plugged in and the power switch is pressed.
• When the on-board power management processor generates a Wake Up on Alarm event (not the same as the APM Wake Up on Alarm).
• When the on-board power management processor generates a Wake Up on Ring event (not the same as the APM Wake Up on Ring).

ON to OFF

The system will transit from ON to OFF under the following conditions:

• When power is removed from the planar or power supply.
• When the power switch is pressed.
• When Shutdown is invoked from the Windows Start Menu.

When BIOS receives an INT 15H call for a power switch press or immediate off.

ON to SUSPEND

The system will transit from ON to SUSPEND under the following conditions:

• When no hardware activity has been detected for the amount of time specified in the Suspend Timer.
• When the Suspend button is pressed on the keyboard.
• When Suspend is invoked from the Windows Start Menu.

ON to STANDBY

The system will transit from ON to STANDBY under the following conditions:

• When no hardware activity has been detected for the amount of time specified in the Suspend Timer, and APM is not connected.
• When BIOS receives a Set Power State Standby call from the operating system.
• When BIOS receives an INT 15H call for immediate Standby.

SUSPEND/STANDBY to ON

The system will transit from SUSPEND or STANDBY to ON under the following conditions:

• When the user initiates hardware activity (like moving the mouse or pressing a key).
• When the power switch is pressed.
• When an APM Wake Up on Alarm event occurs.
• When an APM Wake Up on Ring event occurs.
• When a serial port Wake Up event occurs.

SUSPEND/STANDBY to OFF

The system will transit from SUSPEND or STANDBY to OFF under the following conditions:

• When an unexpected power loss occurs.
• When BIOS receives an INT 15H call for immediate off.

Home Director Support
Intrepid/Defiant BIOS supports Home Director via the following functions:

Wake Up on Alarm from SUSPEND: the Home Director scheduler function may set the Resume timer to bring the system out of SUSPEND at a specified time. This is the same function described in "APM Wake Up Functions".

Serial Port Wake Up from SUSPEND: the Home Director controller may generate a serial port Ring Indicate signal to bring the system out of SUSPEND as a result of an external event. This function is enabled when serial port activity checking is enabled in the Setup Utility.

Wake Up on Alarm from OFF: the Home Director scheduler function may set the on-board power management processor to turn ON at a specified time.

Wake Up on Ring from OFF: the Home Director controller may use the on-board power management processor to turn ON via the serial port Ring Indicate signal as a result of an external event. This function is enabled in BIOS by default.

Quick Boot: occurs when the system turns ON from OFF as a result of a Wake Up event. On a Quick Boot POST will not display the logo, will not enter the Setup Utility, will not generate a beep, will only boot from the hard disk, and boots with the keyboard controller locked. The only way to override a Quick Boot is via a diskette with the Manufacturing signature in the boot record.

Non-APM Power Management:
Intrepid/Defiant BIOS supports the STANDBY state in non-APM environments according to the setting of the Suspend Timer in the Setup Utility. When the specified amount of time expires without hardware activity, BIOS will put the graphics controller in Standby mode and spin down the hard disk. A switch press, hardware activity, or Wake Up event brings the system back to full ON.

Topics/Overview

Intrepid/Defiant Function and Terminology

• Power states: off, Suspend, on
• Suspend: halt CPU and fan, blank screen, spin down disk
• Suspend on Start Menu
• Suspend button on keyboard
• Period of inactivity
• Standby (Suspend to customer): blank screen, spin down disk
• Resume on Ring (Wake up when the phone rings)
• Resume on Alarm (Resume from Suspend)
• Home Director functions
• Wake Up on Ring from off
• Wake Up on Alarm from off
• Quick boot after Wake Up
• Resume from X-10 serial port controller

• Suspend may not be perceived as low power (50% of full power)
• Customers using Suspend are susceptible to AC power loss
• Marginal for Energy Star support (30 watts)

Technical Limitations:

• Windows generates frequent hard disk activity, therefore Disk Drive 1 and 2 activity checking are disabled by default to allow automatic Suspend.

• CD/DVD/Zip Autoplay is not compatible with activity checking for automatic Suspend. Therefore, Disk Drive 3 and 4 activity checking are disabled by default.

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	Hint Category	Power Management
	Date Created	26-02-98
	Last Updated	11-03-99
	Revision Date	10-03-2000
	Brand	IBM Aptiva
	Product Family	Aptiva
	Machine Type	2140, 2142
	Model	All
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