Now, it is clear to me. I was neglecting the high level of the idle state of the UART. Thanks to MicroController and ESP_Sprite.

Thank MicroController for your reply. The U0RXD (GPIO20) is driven by the CP2102 during the ESP32 programming, however after this phase, in the manual, it is reported that GPIO20 can be used as a generic GPIO thanks to proper GPIO matrix configuration. Indeed, I'm able to generate an output PWM sign...

Hello Community, I experienced a strange behavior on the ESP32-C3-DevKitC-02v1.1 module. I configured GPIO10 and GPIO20 to generate two identical PWM output signals. I measured both output signals with an oscilloscope and found that the low level of GPIO20 was not as low as expected. It is close to ...