@Rocka84 @Mahko_Mahko and all - Thank you!
I’ve successfully soldered a cable with rj11 to waveshare esp32-c3-zero and I can control my Ikea Uppspel desk with it.
The only change that I’ve made from the example script is to set the correct rx/tx_pin (GPIO20, GPIO21) in order to receive the initial information about the max/min/current height of the desk.
