【Training Camp】ESP32 Multifunctional Desktop Assistant

Multifunctional desktop assistant based on ESP32-C3-12F

• The screen can display network time
• The time can be set manually and will not be lost when the power is off.
• Display countdown function (in days, for example, XXX days until the CET-4 exam)
• Show English words
• Show school badge logo
• Control computer volume via encoder knob
• 

Design

• The power supply part uses Type-C 5V power supply and is stepped down to 3.3V by LDO.
• Download circuit uses CH340C to realize automatic download circuit
• The main control uses ESP32-12F with WiFi and Bluetooth dual modes, which can realize networking and BLE
• The screen display uses a 1.3-inch LCD_TFT screen, 240*240 resolution, the driver uses ST7789V, and the interface is SPI interface
• The clock chip uses DS1302, which has the characteristics of recording time and not losing power when it is powered off.
• The button interaction uses a patch-type encoder knob, which has button and rotation functions, and can design more interaction methods.

Development ideas

Use the WiFi function of ESP32-12F to connect to the network, obtain the time, parse the json data, obtain the time data, and then display it on the LCD screen.

Use the program to calculate how many days are left between the current time and a certain day, such as CET-4, postgraduate entrance examination date, etc.

The word display part is judged by RTC time. When the interval is greater than the certain value, the next word is refreshed.

At the same time, ESP32-12F also has Bluetooth function. You can use Bluetooth to connect to the computer and control the computer through the HID protocol, such as rotating the button to control the Bluetooth volume.

Shortcomings and later improvement goals

As an ESP32 and it has a screen, it is better to run LVGL. The interface design is also very nice, but time and energy are limited, and LVGL is not adapted to ESP32-C3, so it has not been transplanted yet. I just wrote a simple LCD driver to achieve the best results. Basic display graphics, ASCII code, simple Chinese characters,

Since no font library has been added, the Chinese meaning of the displayed word has not yet been designed.

The speech recognition module has not yet been welded, so many interaction designs have been castrated. Individual debugging has basically passed, but the whole machine has not been jointly debugged.

This development uses the ESP-IDF4.3.1 version. Since I am not very proficient in FreeRTOS, the code is very crude. It only completes the basic functions and may have bugs. It is only used for your reference.