using switches with the KE-USB36FS.
Note:
The KE-USB36FS allows all of the inputs to be activated
simultaneously.
Keyboard Status Light Signals
Keyboard status light drive is available with the KE-USB36FS. The
unit provides a 6 pin header for connection of the Num Lock,
Caps Lock, and Scroll Lock status LEDs. As shown below, the
Anode and Cathode connections for these diodes are labeled on
the board near the 6 pin
LED header.
As with the input header,
this LED header has
.100” spaced pins,
which are suitable for a
variety of connectors. Soldering to the pins is also an acceptable
way to attach wires for connection to your LEDs.
The KE-USB36FS will drive an LED directly from each Anode/
Cathode pair of wires. At 5 volts, the drive current is approximately
10 ma for each LED. The KE-USB36FS
has current limiting resistors built into
the unit, so connection to the user’s
LED may be made directly.
Figure 5
- Status LED connection
Figure 6
- Connection of LEDs to the
Status LED Header
Appendix B:
Operating Tips
The KE-USB36FS is configured as 36 individual inputs, which
are activated by shorting them to the common logic Ground
provided on the header. Since these inputs are individual, they
are completely separate, and cannot produce “ghosting” as in a
matrix application.
Inputs may also be driven from logic gates, provided they do not
drive voltage above the USB 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 KE-USB36FS
input header to the input devices is 10 feet. The recommended
maximum cable length of the USB cable from the computer or
Hub to the KE-USB36FS is 10 feet.
The Trackball header may be used for a Spinner instead of
Figure 14
- Electrical connection example for switches to
KE-USB36FS header
Ground
Input 1
Input 2
Pushbutton
Pushbutton
KE-USB36FS Header
7
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