Modern microcontroller boards, equipped with an ESP32 or an ESP8266, for example, offer a lot of performance for not much money and a high level of programming convenience especially via the Arduino IDE. The over-the-air feature (OTA) is particularly interesting. It enables both program updates and data to be uploaded conveniently via a bootloader using Wi-Fi communication, without the need to physically connect the board to the USB port of a PC or laptop. However, to transmit serial data (such as debugging information) wirelessly, we need another solution.