Datasheet

Intel Desktop Board DP43BF Technical Product Specification

1.7 Real-Time Clock Subsystem

A coin-cell battery (CR2032) powers the real-time clock and CMOS memory. When

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 standby current from the power

supply extends the life of the battery. The clock is accurate to ± 13 minutes/year at

25 ºC with 3.3 VSB applied.

NOTE

If the battery and AC power fail, custom defaults, if previously saved, will be loaded

into CMOS RAM at power-on.

When the voltage drops below a certain level, the BIOS Setup program settings stored

in CMOS RAM (for example, the date and time) might not be accurate. Replace the

battery with an equivalent one. Figure 1 on page 11 shows the location of the battery.

1.8 Legacy I/O Controller

The Legacy I/O controller provides the following features:

• One serial port header

• PS/2-style keyboard/mouse interfaces

• Serial IRQ interface compatible with serialized IRQ support for PCI systems

• Intelligent power management, including a programmable wake-up event interface

• Conventional PCI bus power management support

The BIOS Setup program provides configuration options for the I/O controller.

1.8.1 Serial Port

The board has one serial port header located on the component side of the board. The

serial port supports data transfers at speeds up to 115.2 kb/s with BIOS support.

For information about Refer to

The location of the serial port header Figure 10, page 42

The signal names of the serial port header Table 14, page 44