Default Cmos Ram Setup Values; Real Time Clock; Setting The Clock; Acpi Power Management - VersaLogic Ocelot Reference Manual

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Datasheet of VL-CBR-2012 - 20" 24-BIT LVDS CABLE
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D CMOS RAM S
EFAULT
After CMOS RAM is cleared, the system will load default CMOS RAM parameters the next time
the board is powered on. The default CMOS RAM setup values will be used in order to boot the
system whenever the main CMOS RAM values are blank, or when the system battery is dead or
has been removed from the board.

Real Time Clock

The VL-EPMs-21 features a year 2000-compliant, battery-backed 146818-compatible real-time
clock/calendar chip. Under normal battery conditions, the clock maintains accurate timekeeping
functions when the board is powered off.
S C
ETTING THE LOCK
The CMOS Setup utility (accessed by pressing the Delete key during the early boot cycle) can be
used to set the time and date of the real-time clock.

ACPI Power Management

The VL-EPMs-21 supports the Advanced Configuration and Power Interface (ACPI) via a
LVCMOS-level input or pushbutton (or relay attached to the pushbutton interface). Power
consumption in standby mode is approximately 1 watt. Wakeup typically occurs in 1 to 6
seconds.
Standby mode functionality has been tested under Windows XP and Linux.
S3 S S
LEEP TATE
The ACPI Specification defines the S3 sleeping state as a low wake latency sleeping state where
all system context is lost except system memory. CPU, cache, and chipset context are lost in this
state. The hardware maintains memory context and restores some CPU configuration context.
Control starts from the processor's reset vector after the wake event.
Since the state of the OS and all applications (including open documents) is sustained in main
memory, the system can resume work exactly where it left off. The contents of main memory
when the computer wakes from standby are the same as when it was put into standby.
S
ETUP
To setup the VL-EPMs-21 to use ACPI power management:
1. Verify that the CMOS Setup ACPI setting is set to Enabled. This is the default setting.
2. Install the most current drivers for all system devices. If a driver is not installed in
Windows correctly, an exclamation point will appear before the device name in Device
Manager. Incorrectly installed or older drivers may prevent the system from entering
standby mode.
VL-EPMs-21 Reference Manual
V
ETUP ALUES
System Features
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