ESP32-POE-ISO Use all pins and Ethernet

Started by timmyo, June 29, 2021, 05:08:35 PM

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Im using almost all the pins, some digital out and some as digital in. Iv'e come across some odd problems but cant seem to find any problems with the software, so my question is if this connection is usable:

No sd card
Ethernet With POE (Not using POE yet since i dont know how to activate)
No Wifi
OTA so no usb needed while pins connected.

These are the pins i use:
Pin 5v - 5v in (VIN)
Pin GND - Ground

Pin 0 - Analog In
Pin 1 - Digital Out
Pin 2 - Analog In
Pin 3 - Digital Out
Pin 4 - Analog In
Pin 13 - Digital Out
Pin 14 - Digital Out
Pin 15 - Digital In
Pin 32 - Digital Out
Pin 33 - Digital Out
Pin 34 - Digital Out
Pin 35 - Digital Out
Pin 36 - Analog In
Pin 37 - Analog In

code is 10 files with alot of codes so i wont paste it here, i use PlatformIO with VS code and i did a "playground" program with ethernet active and one problem is that pin 1 always stays high no matter what i do.

My guess is that ethernet uses the Emac or some pins atleast so i cant use them all?

After checking up the pins i will change the pinout to this but the question on if i can use all these pins with Ethernet and POE still remains?

Pin 2 - Digital In
Pin 4 - Digital Out
Pin 5 - Digital Out
Pin 12 - Digital Out
Pin 13 - Digital Out
Pin 14 - Analog In
Pin 15 - Digital Out
Pin 16 - Digital Out
Pin 32 - Digital Out
Pin 33 - Digital Out
Pin 34 - Analog In
Pin 35 - Analog In
Pin 36 - Analog In
Pin 39 - Analog In

I have not tried this yet.


So i found my problem, on the ESP Olimex POE there is pull-up resistors on UEXT pins so pin 39-36-13-5-16 seems to always be 3.3v because of that, in the schematics there is R31,R35,R36,R37 connected to the uext, i will try to remove these and see if that helps.

Other question instead is if there is an ESP32 with ethernet with all pins floating?


Are you trying to use the GPIOs used by the Ethernet chip? You can't do that.
Technical support and documentation manager at Olimex