[Front]
[Next Chapter]
About This Guide
This reference guide is intended for programmers or system builders
who want to implement power saving features into devices using
DR-DOS and the patented (No. 5,355,501) BatteryMAX dynamic idle
detection system.
What is Power Management?
In todays market place, where portability of data is even more
important, there has been a huge increase in the number of portable
devices being manufactured such as laptops, hand-held terminals, and
personal databanks. All of these are required to run on battery
power for as long as possible so the user does not run out of
battery life too quickly and have to keep recharging the battery.
DR-DOS has built in dynamic idle detection which works in
conjunction with a machine dependent loadable device driver
to control the specific hardware you want to power down. Most
modern ROM BIOS software now has a generic interface called the
APM API (Advanced Power Management) which can power down all the
hardware to save battery life. However, you need software to be
able to detect when the system is idle before the APM system can
control the hardware. DR-DOS provides this inthe form of the
BatteryMAX dynamic idle detection and all you need to include
is the separate APM aware device driver that can pass the
messages from DR-DOS to the APM-aware ROM BIOS.
The System Builder Kit provides the necessary device drivers
and tools required to implement either of these solutions in
your devices.
The APM Specification
The Microsoft and Intel specification introduced a hardware
independent interface to a ROM BIOS interface that allows the
operating system, applications and other APM aware drivers to
control the power management hardware. The APM aware drivers
can also be linked to hardware that is not part of the laptop
itself. The interface allows the current power state to be
examined and then to be changed. The ROM BIOS interface can be
used in both real (virtual 86) mode and 16-bit or 32-bit protected mode.
It is important to note that if another operating system is
installed such as Windows, it may extend or even take over the
power management functions of DR-DOS.
Why Use BatteryMAX?
BatteryMAX(TM) uses the technique of dynamic idle detection to
benefit any computer manufacturer who supplies hardware running
off batteries. It can provide significant power savings by detecting
what the software is doing, therefore extending the battery life of
the product. Power saving is achieved by slowing down the CPU or
turning off power to associated hardware, for example.
The extension of battery life provided by BatteryMAX means that
battery-powered hardware can be used away from a mains power
supply for much longer times, and therefore reduces the instances
when the user has to carry a mains power pack.
BatteryMAX can take account of the hardware on which it runs,
which enables OEMs to combine the benefits of BatteryMAX with
the superiority of a particular hardware platform.
What is Involved to Implement Power Saving?
To implement Power Management into your particular device with
Caldera DR-DOS, you can do one of the following:
If you have this type of environment, you need to read the section
APM IDLE DEVICE DRIVER for specific information relating to this driver.
[Front]
[Next Chapter]
info@caldera.com
Copyright © 1976, 1982, 1988, 1990, 1991, 1992 and 1997 Caldera, Inc. All rights
reserved.