[mystified5016]

To chime in, adding the espressif WiFi libraries to your firmware adds 500-600KB of code. In the trivial IoT widget I just made, the firmware is >90% espressif code by weight.

The RAM use is also... noticeable. It takes quite a lot for this chip do WiFi.

[vbezhenar]

It is similar for BLE. I recently wrote firmware for nrf52 device. Proprietary blob was 100 KB. My code was 60 KB and actually like 40-50 KB was caused by crypto library which is basically required part of BLE stack as well, just distributed with code and not in the blob.

[zazaulola]

ESP32 has 18 ADC input channels. But if you are using Wifi, you can only use 8 of the 18 for ADC conversion: GPIO pins 32-39.

Other 10 pins, on which ADC2 channels are possible, can only accept pulse data if you are using Wifi.

This is probably due to firmware limitations.

[mystified5016]

Espressif implies that the WiFi hardware uses ADC2 for something. It sounds like a hardware limitation, a firmware issue would have been patched a long time ago.