ESP32-POE-ISO hangs when mounted to another circuit

Started by wacime, April 19, 2022, 04:34:06 PM

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Hello all,

I am working with the ESP32-POE-ISO board to control other devices. I am using an external circuit (to be made into a PCB) to power the board through its 5V pin. I am doing the programming using OTA and no USB cable is used, so GPIOs 0, 1, and 3 should be used with no apparent problems. But sometimes, when I install the board onto this circuit (using headers), it hangs and does not boot as normal. After doing some research, it appears that it might be entering boot mode and that it is blocked there.

The external circuit is a breakout board and GPIO0 is connected directly to a sprint terminal, no pull-ups or pull-downs are used. The problem happens sometimes when nothing is connected to the terminal. But, it can also happen when a device is connected to the terminal, in which case removing the cable allows the ESP32 to boot normally.

What do you think? Can this be fixed by adding a pull-up? Will it affect the operation of the pin? Should I just avoid it?

Thank you,


Hello again,

I added a 100K pull-up and the issue seems to be fixed.


Hello, I am having the same problem... To what pins did you had a pull-up resistor? Thanks