Hi all. I've come across a weird and frustrating issue. I have a simple reed switch attached to a NodeMCU and the code uploads and executes with no problems UNLESS the reed switch is activated (ie the presence of a magnet means the switch is closed at the time of the upload). If I open the switch by…

ESP8266 (NodeMCU and Wemos D1 mini) won't boot or upload with particular devices

ieee488 April 17, 2018, 3:12pm 2

You're confusing voltage with current.

I suspect your relay when closed is drawing more current than the NodeMCU board can supply.

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