HP Compaq dc71 Series, Technical Reference Manual

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Technical Reference Guide 361834-002 4-21
System Support
4.4.3 Standard CMOS Locations
Table 4-12 describes standard configuration memory locations 0Ah-3Fh. These locations are
accessible through using OUT/IN assembly language instructions using port 70/71h or BIOS
function INT15, AX=E823h.
NOTES:
Assume unmarked gaps are reserved.
Higher locations (>3Fh) contain information that should be accessed using the INT15, AX=E845h
BIOS function (refer to Chapter 8 for BIOS function descriptions).
4.5 System Management
This section describes functions having to do with security, power management, temperature,
and overall status. These functions are handled by hardware and firmware (BIOS) and generally
configured through the Setup utility.
4.5.1 Security Functions
These systems include various features that provide different levels of security. Note that this
subsection describes only the hardware functionality (including that supported by Setup) and
does not describe security features that may be provided by the operating system and application
software.
Table 4-12.
Configuration Memory (CMOS) Map
Location Function Location Function
00-0Dh Real-time clock 24h System board ID
0Eh Diagnostic status 25h System architecture data
0Fh System reset code 26h Auxiliary peripheral configuration
10h Diskette drive type 27h Speed control external drive
11h Reserved 28h Expanded/base mem. size, IRQ12
12h Hard drive type 29h Miscellaneous configuration
13h Security functions 2Ah Hard drive timeout
14h Equipment installed 2Bh System inactivity timeout
15h Base memory size, low byte/KB 2Ch Monitor timeout, Num Lock Cntrl
16h Base memory size, high byte/KB 2Dh Additional flags
17h Extended memory, low byte/KB 2Eh-2Fh Checksum of locations 10h-2Dh
18h Extended memory, high byte/KB 30h-31h Total extended memory tested
19h Hard drive 1, primary controller 32h Century
1Ah Hard drive 2, primary controller 33h Miscellaneous flags set by BIOS
1Bh Hard drive 1, secondary controller 34h International language
1Ch Hard drive 2, secondary controller 35h APM status flags
1Dh Enhanced hard drive support 36h ECC POST test single bit
1Eh Reserved 37h-3Fh Power-on password
1Fh Power management functions 40-FFh Feature Control/Status