SOLVED] Wemos D1 mini - 5v and 3.3v pins - Microcontrollers - Arduino Forum

Hallo Arduino people, Forgive my ignorance, I'm a software developer and don't know much about electronics (yet). I hope you can help me, I've search the internet long enough already without finding answers. The Wemos D1 mini has both 5v and 3.3v pins. I know I can power it via the 5v pin, which is practically the same as powering it via USB. Question 1: Is this pin INput only? I've also noticed a 3.3v pin, in some diagrams also used to connect logic level shifter. Question 2: What's this

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