Specifications

Theory of Operation
Page 35
3 3
Miscellaneous functions
Keyboard controller
A PC-compatible keyboard controller is provided on the board. Connection to it is
made with a 6-pin mini-DIN circular connector, the type used in PS/2 designs and in
other RadiSys CPU designs. This connector is located at the bottom of the AT
bracket along the back edge of the circuit board. The keyboard connections are also
provided in the test connector which is used in manufacturing test. An input is
provided on the miscellaneous connector for the connection of a keylock switch to
disable the keyboard.
There are two jumpers as inputs to the keyboard controller to select color or
monochrome display and to force an update of the system BIOS. Refer to Chapter 2,
Installation and Configuration, for more information.
Power to the keyboard is fused to meet safety agency requirements (e.g., UL1950).
Battery
A built-in socketed coin cell battery is provided for backup of the real-time clock and
CMOS RAM. This cell will be installed at the factory, and is user-replaceable. The
cell used is a 3V lithium coin cell, Panasonic part number BR2330 (250mA-hour) or
equivalent.
Figure 3-1. Replacing the Battery.
1. Gently lift
retaining clip
2. Slide battery
in/out in line with
the direction of the
retaining clip.