Doubts ESP32-POE-ISO Wrover

[Cesarpuig]

Hello.

Please, can you clarify some doubts I have with the pins of the ESP32-POE-ISO Wrover board?

1st The GPIO0 is used for Ethernet, can it no longer be used as input/output?

2nd GPIO16 is used internally and replaced by GPIO33. Is there another GPIO installed on the pin where GPIO33 was?

3rd In the GPIO scheme on their website, they recommend GPIO13 for I2C-SDA and GPIO16 I2C-SCL, but in the Wrover version GPIO16 is used. What GPIOs can I use for I2C?

Thank you so much

[LubOlimex]

The difference in the pinout when using ESP32-WROOM or ESP32-WROVER module is caused by the fact that ESP32-WROVER module uses two of the pins for the PSRAM. So basically ESP32-WROVER has two less free pins. The pins used by ESP32-WROVER for the PSRAM are pins GPIO16 and GPIO17.

1. GPIO0 is used for eMAC clock. It is also a bootstrap pin. It shouldn't be used as GPIO if you want to use Ethernet at the same time. Generally you should be careful with pin GPIO0 since its state might affect the board after reboot.

2. No. As I explained at start - WROVER variant has two GPIOs less since those are used for the PSRAM. But there is no problem to use GPIO33 for I2C.

3. The ESP32 chip has very good multiplexing, you can assign any free GPIO for I2C by software means.

[Cesarpuig]

Thank you so much @LubOlimex