ESP-12e - RX/TX pins flickering on boot when used as GPIO pins I am using ESP-12e as a controller for my garden lights. I am using pins 1 (TX), 3 (RX) and 5 as an analog output (PWM signal with mosfets) for three separate light sets. ESP is powered on when wall switch is turned on (wall switch turns on power adapter). When I turn the switch on, for short period of time lights connected to pin 1 and 3 work at full power and after that they are set according to PWM signal. Lights on pin 5 works just as expected. I am not using Serial communication, just elegantOTA library for OTA updates and async web server. Is it possible to somehow disable RX/TX functionality at all/before they are set to high, or I am forced to solder lights on pins 1 and 3 to another ones? I tried some software tricks I found online, but without success.
According to this reference, GPIOs 1 and 3 have dedicated behaviour during boot (debug output or pulled high) which can not be disabled in your sketch.
You have to either choose different pins or implement an additional circuitry.