Datasheet

Intel Desktop Board D945GSEJT Technical Product Specification
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1.6 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 1-1 on page 11 shows the location of the
battery.
1.7 Legacy I/O Controller
The Legacy I/O Controller provides the following features:
• Two serial ports
• One parallel port with Extended Capabilities Port (ECP) and Enhanced Parallel Port
(EPP) support
• Serial IRQ interface compatible with serialized IRQ support for PCI Conventional
bus systems
• PS/2-style keyboard interface
• Intelligent power management, including a programmable wake-up event interface
• PCI Conventional bus power management support
The BIOS Setup program provides configuration options for the Legacy I/O controller.
1.7.1 Serial Ports
The serial ports, COM 1 and COM 2, are implemented as two 10-pin headers on the
board. The serial ports support data transfers at speeds up to 115.2 kbits/sec with
BIOS support.
For information about Refer to
The location of the serial port headers Figure 2-4, page 39