
L3 Systems
1
5/19/2007
Introduction
The KB232 PS/2 Keyboard RS-232 adapter allows a
PS/2 style keyboard to be connected to an RS-232
port of a computer or other equipment using RS-
232 communications. This allows the use of a
standard “PC” type keyboard for embedded
applications that only have RS-232 interfaces.
Power considerations
The KB232 receives power from the RS-232 inputs
“DTR” on pin 4 and “CTS” on pin 7 of the DB9-S RS-
232 connector. Typically there is enough power
from the RS-232 signals to allow the keyboard to
operate. However, the Caps Lock and Num Lock
LED’s may require more power than the RS-232
port can provide. If this is the case there are three
possible solutions:
The fi rst solution is to use the “CW=” command to
change the KB232 configuration to not turn on
LED’s and thus saving power. (See pages 5 and 6 for
more information on setting configuration values.)
Some keyboards can operate if one LED is active,
but not two. The “CW=” command allows you to
disable both the Caps Lock and Num Lock LED’s or