Below is an application in which the previously implemented (https://github.com/mk590901/ECG-MQTT-SERVICE) mqtt service is used as a app core for the control panel for the microcontroller on the ESP32-S3-WROOM board.

In fact, all control of the controller comes down to changing the color of the RGB LED on the board, so the service is simplified and its functions are reduced to sending commands to change the color and receiving a response.

GUI includes control panel and the mqtt indicator panel. The controller panel is supplemented with a Stop ESP32-S3 button, pressing which leads to the end of the application on the controller.

In addition to the service control panel and the mqtt indicator panel, the GUI is supplemented with a panel of buttons, by pressing which you can change the color of the RGB LED of ESP32-S3 controller. At the bottom of the screen there is an indicator of the selected color. It changes when the application receives asknowledge from the controller.

More details about the command system used and they structure are in the README.md file of the https://github.com/mk590901/TOIT-MQTT-Service repository.

Below are two movies:

Flutter application via that changes colors on the board of microcontroller. You need to press the Start button and after a successful connection to the broker (two green icons - a sign of a successful connection and subscription) you can select a color for the RGB LED. With a slight delay, the color of the ring at the bottom of the screen changes because the reverse passage of the command from the ESP32-S3 to the application take anu time. You can also interrupt the application on the ESP32-S3 by pressing the Stop ESP32-S3 button. If you want to continue, then load the application again to the chip using the jag command.

Live lideo of the reflection of interaction application 1) with the ESP32-S3-WROOM board.