The EMR will turn ON or OFF the DC motor upon receiving an input control signal from the I1 terminal of the Arduino Opta. With the M5Stack Core’s EMR or pushbutton switch contacts wired to the +12 V ...

You can also see a video, below. The demo uses a 3D printer hot end, a thermocouple, a MAX6675 that reads the thermocouple, and an Arduino. There’s also an LCD display and a FET to control the ...