Today, well discuss automation using ESP01 with 16 relays. This is a super cheap design model where you can multiply the modules and get up to 128 relays, as it is possible to put up to eight port expanders in this microcontroller.
In our circuit, you will have an application on a smartphone that communicates with the ESP01. It will have an expander with 16 ports, each connected to a relay. We also have a 3v3 adjustable source. Well therefore control a 16-channel relay module using ESP01 through the Android application, which I make available to you.”

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