Hagstrom KEUSB24 User manual

KEUSB24
PC Keyboard Encoder
User Manual
Toll Free 888-690-9080
Phone: [phone] Fax: [phone]
Monday through Friday, 8:00 am to 5:00 pm (EST)
[email protected]
www.hagstromelectronics.com
1986 Junction Road, Strasburg, VA 22657
Copyright © 2016 HAGSTROM ELECTRONICS, INC.
V. 07.16
HAGSTROM
ELECTRONICS, INC.

Table of Contents
Introduction to the KEUSB24 1
Computer Connections and Device ID Jumper 2
Interfacing to the KEUSB24 I/O Header 3
Status LED Connections 4
The KEUSB24.EXE Program 4
The Program Screen 5
File Menu Selections 7
Sample KEUSB24 Configuration 9
Error Messages 16
KEUSB24 Operating Tips 18
Appendix A: Specifications 19
Appendix B: Command Line Loader 20
Accessories 20
Thank you for purchasing the
HAGSTROM ELECTRONICS, INC.
KEUSB24. This product is configurable
in a variety of ways to meet your specific
requirements. Please take a few minutes to
read this manual before using your KEUSB24.
Warranty
HAGSTROM ELECTRONICS, INC. warrants this
product against defects in material or workmanship for a
period of ONE YEAR fromtheoriginal purchase date. We will
repair or replace (at our option) thereturned defective unit
at no charge during this warranty period.
No responsibility is assumed for any special, incidental,
or consequential damage resulting fromthe use ofor
inability to use this product. In no case is HAGSTROM
ELECTRONICS, INC. to be liable for any amount which
exceeds thepurchase price ofthe unit, regardless ofthe
claim.
No other warranty, written or verbal, is authorized. This
warranty is applicable only to units sold inthe United States.
Units sold outside the United States are covered by a similar
warranty.
Depending on the state in which you live, you may have additional rights.
Great care has been taken during the assembly, testing, and burn-in
of your KEUSB24 to ensure itsperformance. If youhave any questions,
please send us an email or give us a call. Support is available Monday
through Friday, 8:00 am to 5:00 pm (EST).
customer service email: [email protected]
Call Toll Free 888-690-9080, or [phone]
NOTICE The KEUSB24 product is designed to be used by technically
oriented computer users. When the KEUSB24 i si n use, your computer’s
signals and voltages are present on the unit. Prudent handling and
packaging is necessary to prevent damage to your computer.
Your keyboard encoder is designed for OEM use, and is not FCC part 15 approved. Because
the packaging and use oftheproduct will directly affect the characteristics ofthe unit, it isthe
responsibility of the purchaser to obtain final approval of their application, if required.

1
Introduction to the KEUSB24
Our KEUSB24 Keyboard Encoder is a product designed to interface
Keypads, Switches, and/or other contact closures to the computer’s
USB port. Devices connected to the KEUSB24 I/O header produce
keystrokes that appear to the PC as ifthey were entered from a
standard USB keyboard.
The KEUSB24 isfully programmable by the user. This programmability
feature allows the configuration ofthe I/O as well as the selection
of the keystrokes that will be sent to the PC. The KEUSB24 stores
the user’s configuration program in non-volatile memory so that the
information is retained on the unit even after power is turned off.
The KEUSB24 I/O
The 2 x25pin dual rowheader provides 24 I/O signals that can be
programmed to scan any size matrix up to 12 Columns x 12 Rows.
Any of the24 I/O pins may be designated as either a Column or a
Row. The KEUSB24 configures its scanning to the keypad, allowing
the direct connection of many “off the shelf” keypads without any
modified or complicated cabling.
Power Requirements
The KEUSB24 requires no external power source. It is powered directly
from the USB port on the PC.
Supported Computers
All PCs with a standard USB port will work with the KEUSB24. The
KEUSB24.EXE Program is for Windows based systems.
Hardware Requirements
The KEUSB24 is designed to work with standard, commercially
available cables for connection to the PC. An A-B Type USB cable is
required for this connection.
Default Settings
The KEUSB24 isprogrammed and shipped with a default 4x4 matrix
configuration. This default configuration can be changed or modified
at any time by the user.
Accessories
20
KE-USBMM6
6 foot USB Type A to Type B connecting
cable between KEUSB24 and PC.
MTA100-12-12
MTA Harness to connect to the KEUSB24
header. Features a right angle connector
that plugs directly to the I/O header, and
provides 12 inches of discrete wire for
each header pin.
MTA100-12-12
KEUSB24 Header
Appendix B:
Command Line Loader
The KEUSB24 can also be loaded through the command line by using
the supplied KEUSB24LOAD.EXE program. Refer to readme.txt located
under the Command Line Loader folder on the supplied CD ROM for
further details.

Operating Voltage 5 Volts DC +/- 5%
Operating Current 12 ma Typical
Operating Temp. 0 to 70 Degrees C
PC Interface USB
Input Debounce Time 15 - 20 Msec Typical
I/O Header 24 I/O, up to 12x12 Matrix
(programmable)
Appendix A:
KEUSB24 Speci cations
2.0”
2.5”
.125
Dia. (4)
19
2
Computer Connection
There isone USB connector located onthe KEUSB24. Connection
to this port can be made with power on as the KEUSB24 supports
“Hot Plug” operation as a USB device.
The KEUSB24 emulates a standard 104 key USB keyboard
and may be used in addition to or inplace ofthe system’s own
keyboard.
Device ID Jumper
Two KEUSB24 units may be connected
to the same computer and programmed
independently. If using one unit, leave
the Device ID jumper open (factory
default). If using two KEUSB24 units,
leave the jumper open on unit 1, and
closed on unit 2. This setup will present
two different USB devices to the system
that both work as USB keyboards.

KEUSB24 OperatingTips
Please check the following items before contacting us.
• When connecting the KEUSB24 to a PC use a standard
USB A-B type Cable.
•Check the KEUSB24 configuration. Check the I/O
configuration for the number of Columns, Rows, etc.
Review the matrix table for the desired responses.
• The maximum recommended cable length fromthe
computer to the KEUSB24 is10 feet. This distance is also
the maximum length that should be used on connections
fromthe switches or keypads to the KEUSB24 I/O
header.
• If using a Device ID jumper, only make changes to
it when thepower to the unit is off as it is sampled at
power on or reset.
• While the KEUSB24 only scans a matrix, running a
1 x 23 matrix essentially provides 23individual inputs
without the inherent matrix issues.
*Note: For any questions that are not answered in this
manual, please send us an email or call customer service. We
have customer service available from 8:00 am to 5:00 pm (EST)
Monday through Friday.
customer service email: [email protected]
Toll Free 888-690-9080, or [phone]
Interfacingto the KEUSB24 I/O Header
The 2 x25pin dual rowheader on the KEUSB24 consists of24
I/O pins with a Logic Ground at one end. The I/O signals are
labeled onthe KEUSB24 as “A” through “X”. Each pin onthe
dual rowheader is connected inparallel with its adjacent pin.
Therefore, each I/O signal is available on two different pins.
Use the supplied KEUSB24.EXE program to configure the I/O pins
as either Rows or Columns. Keystrokes are initiated by shorting
a Row pinto a Column pinthrough a contact closure. The pins
that are defined as Columns will sink current while scanning the
matrix. The Rows are used to read the status oftheinputs when
a Column is active.
*Note: The switch, keypad, or input device that is used must
be capable of carrying at least 1mA of current. In addition to
switches and keypads, other electronic circuits may also be used
to generate keystrokes, provided that they do not exceed the 5
volt logic level range of the KEUSB24 I/O.
3
Figure 1.1
Inputs are activated by
shorting a pin defined
as a Row to a pin
defined as a Column.
Column Column
Row
18

17
“Error savingle”
This error message is shown ifthe KEUSB24.EXE program
attempts to save a file that is already open in another application,
or if there is not enough disk space. If this happens, close the
other application and try saving the file again.
“Error:Pin *is used for multiple scan lines”
If a header pin is used to designate more than one rowor column
or is used for both a row and a column, this error will be displayed
when saving the configuration to a file or to the KEUSB24. Check
the matrix configuration and eliminate redudant pin letters.
The error message will give the letter of theproblematic pin
(Example: “Error: Pin D is used for multiple scan lines”).
The KEUSB24.EXE Program
The KEUSB24 unit is shipped with a CD ROM containing the
KEUSB24.EXE utility program which is used for configuring the
unit. Configuration parameters include the defining of the I/O
pins as Rows and Columns, the keystrokes generated by the
contact closures, as well as other various options.
GettingStarted
To begin using the KEUSB24, follow the steps listed below.
1. Attach the KEUSB24 to the computer as described on
page 2 under the section “Computer Connections.”
2.Insert the CD and save the content to its own folder
on thehard drive. The CD may now be removed and
stored in a safe location for future use.
3. Open the folder that was created in step 2 and start
the configuration program by selecting the program
file KEUSB24.EXE.
*Note: The programs must be copied to and run from its own
folder on the PC’s hard drive. The CD itself should be reserved
for back up purposes only.
4
Status LEDConnections
The KEUSB24 features a 2 x 3 header for driving the three status
LEDs for Num, Caps, and Scroll Lock.Connect LEDs as shown to
use this drive capability. No external current limiting resistors are
required as they are supplied on the board.

The ProgramScreen
The main program screen displays the configuration settings for
the KEUSB24. A list of these settings and a description ofhow
they pertain to the KEUSB24 setup are listed below.
*Note: The number of Rows plus the number of Columns
cannot exceed the total number of 24 I/O pins. For example, 5
Rows + 12 Columns = 17 I/O pins.
Number ofRows:The number of Rows are selected from
the drop down list. This may be any value from 1 to 23.
Number ofColumns:The number of Columns are selected
from the drop down list. This may be any value from 1 to 23.
5
Error Messages
“The KEUSB24 was notfound”
This error occurs ifthe computer cannot communicate with the
KEUSB24 when trying to save to the KEUSB24 or read fromthe
KEUSB24. Check the cable connections to make sure none of
them are loose or unplugged. Check the Device ID jumper.
“Error while readingfromthe KEUSB24”
“Error while writingto the KEUSB24”
This indicates that, while the computer can communicate with
the KEUSB24, it was not able to read or write the configuration.
Communication may be interrupted if a user presses a key on
the keyboard or if another program takes the focus away from
the KEUSB24 application. If this error message is displayed,
load the configuration again.
16
“Invalid con guration”
“Invalid con guration le”
When loading an already existing configuration from a file or
uploading a configuration fromthe KEUSB24, theprogram will
give this error message ifthe file is corrupted or ifit isthe wrong
file type.
“Error openingthe le”
This error message is shown ifthe KEUSB24.EXE program
attempts to o pen a file th at is already open i n another application.
If this happens, close theother application and open the file
again.

Step5
Now that the setup is complete, it can be saved to disk. Specify
a file name under which to save the configuration.
Step6
Load the KEUSB24 with the configuration. Be sure that the
KEUSB24 is connected to the PC. Once the KEUSB24 is loaded,
it will begin running the new setup.
15
Typematic:The typematic option controls the enable or
disable ofthe KEUSB24 repeat function. Typically on a PC
keyboard when a key is held down, it will begin to repeat after
a short delay. This function can be duplicated by the devices
connected to the KEUSB24 I/O header by enabling this option.
Enabling this option will affect all keys within the matrix. The
rate at which the key will repeat is the same as your PC keyboard
settings onthe PC. With this option disabled, the keystrokes
being generated fromthe devices attached to the KEUSB24 will
produce one keystroke per activation.
*Note: The Typematic Enable/Disable option only applies to
the devices connected to the KEUSB24 I/O header. It will not
affect the repeat functions of the PC keyboard.
Column Pin Assignments:Column pin assignments are
selected fromtheir corresponding drop down list. Each column
must have an I/O pin assigned to it. Specify any I/O pin “A”
through “X” as a column.
RowPin Assignments:Row pin assignments are selected
fromtheir corresponding drop down list. Each row must have an
I/O pin assigned to it. Specify any I/O pin “A” through “X” as a
row.
*Note: A pin cannot be assigned to both a Column and a
Row.
6

File Menu Selections
These selections, located within a drop down list, are accessed
by clicking on “File” inthe upper left corner of the main program
screen. This list provides several options that include creating
and saving file configurations as well as reading and writing to
the KEUSB24. A list of these options along with descriptions of
how they pertain to the KEUSB24 setup are listed below.
7
New: Creates a new configuration file by either clicking on
“New” with the mouse or by pressing Ctrl+N onthe keyboard.
This option will also return theprogram screen to the default
settings.
14
The following diagram shows the completed setup created in
this example. Notethepresence of modifier keys in Row 4, Col
3 and Row 4, Col 4.

Step4
The KEUSB24 has the capability to assign Shift, Ctrl, and Alt
functions along with a keystroke. For this sample setup, one of
the keys is defined as theCtrl+Alt+Del sequence. The keystrokes
emulated by this combination have the same effect as holding
the control and alt keys, then pressing the delete key on a PC
keyboard. To create this input, check theCtrl and Alt boxes on
the lower left corner of the keyboard diagram, then click onthe
Del button (shown below).
Any position inthe KEUSB24 matrix can be modified by one or a
combination oftwo of the Shift, Alt, or Ctrl keys using the method
described above. Use the Shift function to generate upper case
characters, or shifted characters (!, @, etc.) inthe application. To
remove one ofthese special functions, uncheck the appropriate
box and click on the desired key.
138
Open:Recall a previously saved configuration file by either
clicking on “Open” with the mouse or by pressing Ctrl+O onthe
keyboard. Locate and select the name ofthe configuration file
on the PC that is to be opened.
Save:Once a configuration setup has been created onthe
program screen, it isrecommended that it be saved onthe PC’s
hard disk. Click on “Save” with the mouse or press Ctrl+S onthe
keyboard, then choose a location to save the file.
Read fromKEUSB24 (1): This option will read the current
configuration inthe KEUSB24 and display it on the screen. Click
on “Read from KEUSB24” with the mouse or press Ctrl+R onthe
keyboard to perform this operation.
Write to KEUSB24 (1): This option will write the current
configuration displayed onthe screen to the KEUSB24. The
KEUSB24 can be programmed and re-programmed as many
times as necessary.Click on “Write to KEUSB24” with the mouse
or press Ctrl+W onthe keyboard to perform this operation. After
the KEUSB24 has been loaded with the new configuration, it will
scan according to this new setup.
Read fromKEUSB24 (2): This option will read the current
configuration from a unit configured as Device ID 2.
Write to KEUSB24 (2): This option will write the current
configuration from a unit configured as Device ID 2.
Exit: This option exits and closes the KEUSB24.EXE program.
*Note: Make sure that the KEUSB24 is connected to the PC
before performing either the “Read to KEUSB24” or “Write to
KEUSB24” operations. If the KEUSB24 is not present, a “The
KEUSB24 was not Found” error will be displayed on the computer
screen.

Sample KEUSB24 Con guration
The following exercise demonstrates howto program the
KEUSB24 to scan a keypad. The keypad inthe example is a 4x4
matrix (16 key) device.
Step1
Select the Number of Rows onthe screen and set it to 4. Select
the Number of Columns, and set that value to 4 as well. The
screen should appear as shown below.
912
Continue selecting each position inthe matrix and assign the
desired keys fromthe keyboard diagram until the matrix is
finished.
In the example illustrations, the user clicked matrix position
Row 1, Col 3 and assigned the key “C” to it.

10
Step2
Now that the size ofthe matrix to be scanned has been selected,
the pins ofthe KEUSB24 I/O header to be used as rows and
columns must be selected. The keypad example has 8 interface
pins. The easiest way to plug the keypad inisto attach it 1:1 to
the I/O header. For this example, theheader pins “A” through
“H” are used as the connection point.
*Note: Any 8 of the KEUSB24 pins could have been used for
this example.
Since theColumns and Rows for the example keypad are
intermixed,thepin definitions for the Rows and Columns must
be assigned. Highlight the Column pin designations, and assign
them as follows:
Col 1 = Pin D, Col 2 = Pin A, Col 3 = Pin G, Col 4 = Pin H
Select the Row Pin definitions next, and change them to:
Row 1 = Pin E, Row 2 = Pin C, Row 3 = Pin F, Row 4 = Pin B
Step3
With the size ofthe matrix now defined, and the I/O pins selected,
assign the keys to be emulated to each position inthe matrix.
To assign keys, click onthe desired matrix position. A diagram
of the keyboard will be displayed, as shown below. Click onthe
representation of the key to assign it to the matrix position.
11

10
Step2
Now that the size ofthe matrix to be scanned has been selected,
the pins ofthe KEUSB24 I/O header to be used as rows and
columns must be selected. The keypad example has 8 interface
pins. The easiest way to plug the keypad inisto attach it 1:1 to
the I/O header. For this example, theheader pins “A” through
“H” are used as the connection point.
*Note: Any 8 of the KEUSB24 pins could have been used for
this example.
Since theColumns and Rows for the example keypad are
intermixed,thepin definitions for the Rows and Columns must
be assigned. Highlight the Column pin designations, and assign
them as follows:
Col 1 = Pin D, Col 2 = Pin A, Col 3 = Pin G, Col 4 = Pin H
Select the Row Pin definitions next, and change them to:
Row 1 = Pin E, Row 2 = Pin C, Row 3 = Pin F, Row 4 = Pin B
Step3
With the size ofthe matrix now defined, and the I/O pins selected,
assign the keys to be emulated to each position inthe matrix.
To assign keys, click onthe desired matrix position. A diagram
of the keyboard will be displayed, as shown below. Click onthe
representation of the key to assign it to the matrix position.
11

Sample KEUSB24 Con guration
The following exercise demonstrates howto program the
KEUSB24 to scan a keypad. The keypad inthe example is a 4x4
matrix (16 key) device.
Step1
Select the Number of Rows onthe screen and set it to 4. Select
the Number of Columns, and set that value to 4 as well. The
screen should appear as shown below.
912
Continue selecting each position inthe matrix and assign the
desired keys fromthe keyboard diagram until the matrix is
finished.
In the example illustrations, the user clicked matrix position
Row 1, Col 3 and assigned the key “C” to it.

Step4
The KEUSB24 has the capability to assign Shift, Ctrl, and Alt
functions along with a keystroke. For this sample setup, one of
the keys is defined as theCtrl+Alt+Del sequence. The keystrokes
emulated by this combination have the same effect as holding
the control and alt keys, then pressing the delete key on a PC
keyboard. To create this input, check theCtrl and Alt boxes on
the lower left corner of the keyboard diagram, then click onthe
Del button (shown below).
Any position inthe KEUSB24 matrix can be modified by one or a
combination oftwo of the Shift, Alt, or Ctrl keys using the method
described above. Use the Shift function to generate upper case
characters, or shifted characters (!, @, etc.) inthe application. To
remove one ofthese special functions, uncheck the appropriate
box and click on the desired key.
138
Open:Recall a previously saved configuration file by either
clicking on “Open” with the mouse or by pressing Ctrl+O onthe
keyboard. Locate and select the name ofthe configuration file
on the PC that is to be opened.
Save:Once a configuration setup has been created onthe
program screen, it isrecommended that it be saved onthe PC’s
hard disk. Click on “Save” with the mouse or press Ctrl+S onthe
keyboard, then choose a location to save the file.
Read fromKEUSB24 (1): This option will read the current
configuration inthe KEUSB24 and display it on the screen. Click
on “Read from KEUSB24” with the mouse or press Ctrl+R onthe
keyboard to perform this operation.
Write to KEUSB24 (1): This option will write the current
configuration displayed onthe screen to the KEUSB24. The
KEUSB24 can be programmed and re-programmed as many
times as necessary.Click on “Write to KEUSB24” with the mouse
or press Ctrl+W onthe keyboard to perform this operation. After
the KEUSB24 has been loaded with the new configuration, it will
scan according to this new setup.
Read fromKEUSB24 (2): This option will read the current
configuration from a unit configured as Device ID 2.
Write to KEUSB24 (2): This option will write the current
configuration from a unit configured as Device ID 2.
Exit: This option exits and closes the KEUSB24.EXE program.
*Note: Make sure that the KEUSB24 is connected to the PC
before performing either the “Read to KEUSB24” or “Write to
KEUSB24” operations. If the KEUSB24 is not present, a “The
KEUSB24 was not Found” error will be displayed on the computer
screen.

File Menu Selections
These selections, located within a drop down list, are accessed
by clicking on “File” inthe upper left corner of the main program
screen. This list provides several options that include creating
and saving file configurations as well as reading and writing to
the KEUSB24. A list of these options along with descriptions of
how they pertain to the KEUSB24 setup are listed below.
7
New: Creates a new configuration file by either clicking on
“New” with the mouse or by pressing Ctrl+N onthe keyboard.
This option will also return theprogram screen to the default
settings.
14
The following diagram shows the completed setup created in
this example. Notethepresence of modifier keys in Row 4, Col
3 and Row 4, Col 4.

Step5
Now that the setup is complete, it can be saved to disk. Specify
a file name under which to save the configuration.
Step6
Load the KEUSB24 with the configuration. Be sure that the
KEUSB24 is connected to the PC. Once the KEUSB24 is loaded,
it will begin running the new setup.
15
Typematic:The typematic option controls the enable or
disable ofthe KEUSB24 repeat function. Typically on a PC
keyboard when a key is held down, it will begin to repeat after
a short delay. This function can be duplicated by the devices
connected to the KEUSB24 I/O header by enabling this option.
Enabling this option will affect all keys within the matrix. The
rate at which the key will repeat is the same as your PC keyboard
settings onthe PC. With this option disabled, the keystrokes
being generated fromthe devices attached to the KEUSB24 will
produce one keystroke per activation.
*Note: The Typematic Enable/Disable option only applies to
the devices connected to the KEUSB24 I/O header. It will not
affect the repeat functions of the PC keyboard.
Column Pin Assignments:Column pin assignments are
selected fromtheir corresponding drop down list. Each column
must have an I/O pin assigned to it. Specify any I/O pin “A”
through “X” as a column.
RowPin Assignments:Row pin assignments are selected
fromtheir corresponding drop down list. Each row must have an
I/O pin assigned to it. Specify any I/O pin “A” through “X” as a
row.
*Note: A pin cannot be assigned to both a Column and a
Row.
6

The ProgramScreen
The main program screen displays the configuration settings for
the KEUSB24. A list of these settings and a description ofhow
they pertain to the KEUSB24 setup are listed below.
*Note: The number of Rows plus the number of Columns
cannot exceed the total number of 24 I/O pins. For example, 5
Rows + 12 Columns = 17 I/O pins.
Number ofRows:The number of Rows are selected from
the drop down list. This may be any value from 1 to 23.
Number ofColumns:The number of Columns are selected
from the drop down list. This may be any value from 1 to 23.
5
Error Messages
“The KEUSB24 was notfound”
This error occurs ifthe computer cannot communicate with the
KEUSB24 when trying to save to the KEUSB24 or read fromthe
KEUSB24. Check the cable connections to make sure none of
them are loose or unplugged. Check the Device ID jumper.
“Error while readingfromthe KEUSB24”
“Error while writingto the KEUSB24”
This indicates that, while the computer can communicate with
the KEUSB24, it was not able to read or write the configuration.
Communication may be interrupted if a user presses a key on
the keyboard or if another program takes the focus away from
the KEUSB24 application. If this error message is displayed,
load the configuration again.
16
“Invalid con guration”
“Invalid con guration le”
When loading an already existing configuration from a file or
uploading a configuration fromthe KEUSB24, theprogram will
give this error message ifthe file is corrupted or ifit isthe wrong
file type.
“Error openingthe le”
This error message is shown ifthe KEUSB24.EXE program
attempts to o pen a file th at is already open i n another application.
If this happens, close theother application and open the file
again.

17
“Error savingle”
This error message is shown ifthe KEUSB24.EXE program
attempts to save a file that is already open in another application,
or if there is not enough disk space. If this happens, close the
other application and try saving the file again.
“Error:Pin *is used for multiple scan lines”
If a header pin is used to designate more than one rowor column
or is used for both a row and a column, this error will be displayed
when saving the configuration to a file or to the KEUSB24. Check
the matrix configuration and eliminate redudant pin letters.
The error message will give the letter of theproblematic pin
(Example: “Error: Pin D is used for multiple scan lines”).
The KEUSB24.EXE Program
The KEUSB24 unit is shipped with a CD ROM containing the
KEUSB24.EXE utility program which is used for configuring the
unit. Configuration parameters include the defining of the I/O
pins as Rows and Columns, the keystrokes generated by the
contact closures, as well as other various options.
GettingStarted
To begin using the KEUSB24, follow the steps listed below.
1. Attach the KEUSB24 to the computer as described on
page 2 under the section “Computer Connections.”
2.Insert the CD and save the content to its own folder
on thehard drive. The CD may now be removed and
stored in a safe location for future use.
3. Open the folder that was created in step 2 and start
the configuration program by selecting the program
file KEUSB24.EXE.
*Note: The programs must be copied to and run from its own
folder on the PC’s hard drive. The CD itself should be reserved
for back up purposes only.
4
Status LEDConnections
The KEUSB24 features a 2 x 3 header for driving the three status
LEDs for Num, Caps, and Scroll Lock.Connect LEDs as shown to
use this drive capability. No external current limiting resistors are
required as they are supplied on the board.

KEUSB24 OperatingTips
Please check the following items before contacting us.
• When connecting the KEUSB24 to a PC use a standard
USB A-B type Cable.
•Check the KEUSB24 configuration. Check the I/O
configuration for the number of Columns, Rows, etc.
Review the matrix table for the desired responses.
• The maximum recommended cable length fromthe
computer to the KEUSB24 is10 feet. This distance is also
the maximum length that should be used on connections
fromthe switches or keypads to the KEUSB24 I/O
header.
• If using a Device ID jumper, only make changes to
it when thepower to the unit is off as it is sampled at
power on or reset.
• While the KEUSB24 only scans a matrix, running a
1 x 23 matrix essentially provides 23individual inputs
without the inherent matrix issues.
*Note: For any questions that are not answered in this
manual, please send us an email or call customer service. We
have customer service available from 8:00 am to 5:00 pm (EST)
Monday through Friday.
customer service email: [email protected]
Toll Free 888-690-9080, or [phone]
Interfacingto the KEUSB24 I/O Header
The 2 x25pin dual rowheader on the KEUSB24 consists of24
I/O pins with a Logic Ground at one end. The I/O signals are
labeled onthe KEUSB24 as “A” through “X”. Each pin onthe
dual rowheader is connected inparallel with its adjacent pin.
Therefore, each I/O signal is available on two different pins.
Use the supplied KEUSB24.EXE program to configure the I/O pins
as either Rows or Columns. Keystrokes are initiated by shorting
a Row pinto a Column pinthrough a contact closure. The pins
that are defined as Columns will sink current while scanning the
matrix. The Rows are used to read the status oftheinputs when
a Column is active.
*Note: The switch, keypad, or input device that is used must
be capable of carrying at least 1mA of current. In addition to
switches and keypads, other electronic circuits may also be used
to generate keystrokes, provided that they do not exceed the 5
volt logic level range of the KEUSB24 I/O.
3
Figure 1.1
Inputs are activated by
shorting a pin defined
as a Row to a pin
defined as a Column.
Column Column
Row
18