Filter
Top Products
Chapter 2. System board features
Real-time clock and CMOS
The real-time clock is a low-power clock that provides a time-of-day clock and a calendar. The clock
settings are maintained by an external battery source of 3 V dc.
The system uses 242 bytes of complementary metal-oxide semiconductor (CMOS) memory to store data.
The CMOS memory is erased if the jumper on the system board is moved.
To locate the battery, see “System board, Types 6584 and 6594” on page 13.
Flash EEPROM
The system board uses 4 Megabits (Mb) of flash electrically erasable, programmable, read-only memory
(EEPROM) to store the basic input/output system (BIOS), video BIOS, IBM logo, Configuration/Setup
Utility, and Plug and Play data.
If necessary, the EEPROM can be easily updated using a stand-alone utility program that is available on a
3.5-inch diskette.
Expansion adapters
Each PCI-expansion connector is a 32-bit slot. PCI-expansion connectors support the 32-bit 5 V dc,
local-bus signalling environment that is defined in
PCI Local Bus Specification 2.1
.
The PC 300PL Personal Computer has four PCI slots to support the addition of adapters. For information
on installing adapters, see
PC 300PL User Guide
.
For information on the connector pin assignments, see “PCI connectors” on page 27.
Physical layout
The system board might look slightly different from the one shown.
Note: A diagram of the system board, including switch and jumper settings, is attached to the underside
of the computer cover.
12 Technical Information Manual