PCB Antenna Keep-Out Zone Guide

vasy_skral

What pins are input only?

3 days

flux

0:17

Considering file search.

On the ESP32-WROOM-32, the input-only GPIOs are:

Input-only pins

GPIO	Notes
GPIO34	Input only
GPIO35	Input only
GPIO36	Input only
GPIO39	Input only

Important restriction

These pins are GPI only:

No output capability
No internal pull-up
No internal pull-down

So if you use them for switches or logic inputs, you need external bias resistors if the signal source does not already provide a defined level.

If you want, I can also list the pins that should be avoided at boot separately from the input-only pins.

Specify the part

Check U1 pins

Use the datasheet

3 days

Reviews

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