ESP32 - Measuring 3.0V on some GPIOS

[velmurugan7kmvs]

GPIO_Measurement.PNG (28.94 KiB) Viewed 1549 times

Hi All, Why do i measure only 3.0V on some GPIOs?

[mikemoy]

Have you tried say a 10k resistor ?

[ESP_Sprite]

General measuring instruments (like a multimeter or a scope) do not have infinite input impedance, and show up as a high-valued (e.g 10Mohm) resistor to ground. With your 1Mohm resistor, this forms a voltage divider, and 1Mohm/10Mohm would indeed give you 3.0V. GPIO15 is a bootstrap pin and may still have an internal (50K-ish) pullup enabled, hence it still reading 3.3V.