Keyboard And Mouse Interface; Real-Time Clock, Cmos Ram, And Battery - Intel VS440FX Technical Specification

VS440FX Motherboard Technical Product Specification

1.8.4 Keyboard and Mouse Interface

PS/2 keyboard and mouse connectors are located on the back panel of the motherboard. The 5 volt
lines to these connectors are protected with a PolySwitch
reestablishes the connection after an over-current condition is removed. While this device
eliminates the possibility of having to replace a fuse, power to the computer should be turned off
before connecting or disconnecting a keyboard or mouse.
NOTE
You can plug the mouse and keyboard into either connector.
The keyboard controller contains the AMI Megakey keyboard and mouse controller code, which
provides the traditional keyboard and mouse control functions, and also supports Power On/Reset
password protection. A Power On/Reset password can be specified in the Setup program.
The keyboard controller also supports the following hot-key sequences:
<CTRL><ALT><DEL> Software reset. This key sequence resets the computer's software by
jumping to the beginning of the BIOS code and running the Power On Self Test (POST).
<CTRL><ALT><+> and <CTRL><ALT><-> Turbo mode. Note that Turbo mode could be
affected by the operating system, or whether the processor is in protected mode or virtual
x86 mode.
<CTRL><ALT><-> For Deturbo mode (emulates a 23 MHz AT)
<CTRL><ALT><+> For Turbo mode
<CTRL><ALT><defined in Setup> Power management. This key sequence invokes power
managed mode, which reduces the computer's power consumption while maintaining its ability
to service external interrupts.
<CTRL><ALT><defined in Setup> Keyboard lock. This key sequence is a security feature
that locks the keyboard until the User password is entered. When keyboard lock is invoked,
the keyboard LEDs flash. To enable the keyboard lock feature, a User password must be
specified in the Setup program.

1.8.5 Real-Time Clock, CMOS RAM, and Battery

The real-time clock is compatible with DS1287 and MC146818 components. It provides a time-
of-day clock and a 100-year calendar with alarm features and century rollover. The real-time clock
also supports 242-bytes of battery-backed CMOS RAM in two banks, which are reserved for
BIOS use.
The time, date, and CMOS values can be specified in the Setup program. The CMOS values can
be returned to their defaults by using the Setup program or by setting a configuration jumper on the
motherboard.
An external coin-cell battery powers the real-time clock and CMOS memory. If the computer is
not plugged into a wall socket, the battery has an estimated life of three years. When the computer
is plugged in, the 5 volt standby current from the motherboard's power supply extends the life of
the battery. The RTC is accurate to ±13 minutes/year at 25 ºC and 5 V conditions.
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circuit that, like a self-healing fuse,