ESP32 GPIO Pinout Constraints

ESP32 Pin Limitations Input Only: GPIO 34, 35, 36, 39 (No internal pull-ups). Strapping Pins: GPIO 0, 2, 5, 12, 15 (State affects boot-up mode). Internal Flash: Avoid GPIO 6, 7, 8, 9, 10, 11 (Connected to the flash chip). ADC2: Avoid using ADC2 pins (GPIO 0, 2, 4, 12-15, 25-27) if Wi-Fi is active, as they share hardware.

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