HP KAYAK XU800 manual Bxt½rz, Ists Xt Qt¼t ‘tp bxt K½rz, For these three counters

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The Input/Output Controller Hub (82801AA)

bx•t½rz	The timer/counter block contains three counters that are equivalent in
	function to those found in one 82C54 programmable interval counter/timer.
	These three counters are combined to provide the system timer function,
	and speaker tone. The 14.318 MHz oscillator input provides the clock source
	for these three counters.

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Incorporated in the ICH, the APIC can be used in either single-processor or multi-processor systems, while the standard interrupt controller supports only single-processor systems.

The RTC is 146818A-compatible, with 256 bytes of CMOS. The RTC performs two key functions: keeping track of the time of day and storing system data.

The RTC operates on a 32.768 kHz crystal and a separate 3V lithium battery that provides up to 7 years of protection for an unplugged system. It also supports two lockable memory ranges. By setting bits in the configuration space, two 8-byte ranges can be locked to read and write accesses. This prevents unauthorized reading of passwords or other security information. Another feature is a date alarm allowing for a schedule wake-up event up to 30 days in advance.

The ICH’s power management functions include enhanced clock control, local and global monitoring support for 14 individual devices, and various low-power (suspend) states. A hardware-based thermal management circuit permits software-independent entry points for low-power states.

The ICH includes full support for the Advanced Configuration and Power Interface (ACPI) specifications.

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