Appendix B:
KE72 Input Interface
The KE72 is configured as 72 individual inputs, which are
activated by shorting them to the common Ground provided
on the input headers. Since these inputs are individual, they are
completely separate, and cannot produce “ghosting” as in a
matrix application. The KE72 inputs are debounced for use of
mechanical switches for input to the header.
KE72 Inputs may also be driven from logic gate outputs, provided
they do not drive voltage above the 5V supply on the unit. The
logic signals must produce an active logic low signal for the
appropriate amount of time as listed in Appendix A.
The recommended maximum cable length from the KE72
input header to the input devices is 10 feet. The recommended
maximum cable length of the PS/2 cable from the PC to the KE72
is 10 feet.
Note:
The KE72 allows any number of the 72 inputs to be activated
simultaneously. The responses to each input will be processed in the order they
are detected.
Ground
Input 1
Input 2
Pushbutton
Pushbutton
KE72 Header Connection
7
Creating a KE72 Confi guration File
The KE72 is programmed by a configuration file which is a simple
text file created by the user that tells the unit what responses to
generate for activity on each of the KE72 inputs. This configuration
file is loaded into the KE72 by use of the utlility programs included
with the KE72 and detailed in the next section of the manual.
Responses assigned to an input may be a single keystroke, or a
series of keystrokes, making the KE72 a very powerful and flexible
unit. The rules of creating the text file for the KE72 are simple and
versatile. The following examples demonstrate the text required in
the configuration file to define the response of an input.
Each input definition line begins with INXX:, where XX is a two
digit decimal number between 01 and 72. This number indicates
which input the line refers to for the keystroke response. The
keystroke definition for an input is generally encased by square
brackets [ ].
Example Configuration Lines:
IN01:[A]
The line above will program input #1 to produce the “A” keystroke
when the input is activated.
IN22:[F1]
The above text will program input #22 to emulate the F1 key.
IN63:[Home]
The line above will program input #63 to emulate the Home
key.
In addition to emulating a single keystroke, an input may be
programmed to produce a sequence of keystrokes as well. The
Electrical connection example for switches to KE72 inputs.
20
Com
Com
N.O.
N.O.
