weird behaviour with potentiometers

[yann2084]

i have connected four potis with each 100k to gpio 12,13,14, 27.
if the potis are full open, wiper at 3.3v i can't upload anything. arduino ide fails to proceed.. if the potis are in the middle or closed, wipers at gnd everything is fine. i tried different poti values first 20k now 100k. same behaviour. is this normal? do i better use higher even values like 500k or more...or is it some to take as given, work with it?
any hints?

[ESP_krzychb]

Hi yann2084,

Do you use a board with ESP32?

If so then repeat your test with a different pin instead of GPIO12.
If it helps then see https://www.esp32.com/viewtopic.php?t=5970 or https://docs.espressif.com/projects/esp ... other-pins for more information on what is happening.
In short, GPIO12 (MTDI) binary state is read on reset to set the voltage of the ESP32's flash. Uploading will likely fail if the voltage selection is incorrect.

There is also an option to disable the strapping functionality if you have to use GPIO12 like that, see https://docs.espressif.com/projects/esp ... e-vdd-sdio