Matrix Orbital DD-DB1 LCD/VFD Dev Board - Manual (Page 16)

Keypad
Mating Cables KPP4X4
Facilitating user input, the keypad interface header allows a Matrix Orbital or any other passive matrix style input device
to be attached to the DevDevil in a 5x5 row, column format. A customizable value is returned to the host each time one of
the five row pins is connected to a column pin. Two additional pins are offered on either side of these inputs to provide a
single ground and a selectable ground or power pin to provide grounding or backlight capabilities to an external input
device. Alternatively, some of the row and column inputs are doubled on the keypad layout onboard for quick testing as
per the legend provided on the module.
General Purpose Output
A total of six devices can be driven using the general purpose outputs available on the DevDevil. Each output 5V, 20mA
output can be software toggled. Indicator LEDs can be activated by jumping LED Enable. These outputs are most
commonly drive transistor circuitry to provide switching capability.
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Illustration 13: Keypad Header and Buttons
Illustration 14: General Purpose Outputs, Indicators, and Indicator Enable