PES-2602 is an easy-to-use 4-port Input Expansion Board for Arduino Uno and Mega, which allows Arduino to monitor state of DC electric device. In addition, it can monitor NPN, PNP and dry contact(relay).
Library and example for the 4-port input expansion board are part of of
PhpocExpansion library for Arduino. The library reference is available
here.
This tutorial shows how to use 4-port input expansion board with an example of PhpocExpansion library for Arduino.
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