Chapter 8 System BIOS

8.5.3 TEMPERATURE STATUS

The BIOS includes a function (INT15, AX=E816h) to retrieve the status of a system’s interior temperature. This function allows an application to check whether the temperature situation is at a Normal, Caution, or Critical condition.

8.5.4 DRIVE FAULT PREDICTION

The Compaq BIOS directly supports Drive Fault Prediction for IDE-type hard drives. This feature is provided through two Client Management BIOS calls. Function INT 15, AX=E817h is used to retrieve a 512-byte block of drive attribute data while the INT 15, AX=E81Bh is used to retrieve the drive’s warranty threshold data. If data is returned indicating possible failure then the following message is displayed:

“1720-SMART Hard Drive detects imminent failure”

8.6POWER MANAGEMENT FUNCTIONS

The BIOS provides two types of power management support: independent PM support ACPI support.

NOTE: The D315 models support both the independent PM (aka “APM”) and the ACPI Modes. The d325 models support only the ACPI mode.

8.6.1 INDEPENDENT PM SUPPORT (D315 only)

The BIOS can provide power management (PM) of the system independently from an operating system that doesn’t support APM (including DOS, Unix, NT & older versions of OS/2). In the Independent PM environment the BIOS and hardware timers determine when to switch the system to a different power state. State switching is not reported to the OS.

8.6.1.1 Staying Awake In Independent PM

There are two "Time-out to Standy" timers used in independent PM: the System Timer and the IDE Hard Drive Timer.

8-14Compaq D315 and hp d325 Personal Computers

Featuring the AMD Athlon XP Processor

Second Edition - April 2003

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HP manual Temperature Status, Drive Fault Prediction, Power Management Functions, Independent PM Support D315 only