The photo shows the ESP32-S3-Box with pitch bend slider connected to a MacBook. The MacBook is running receivemidi to show the MIDI pitch bend messages. The moire pattern and blue splotches are not visible to the naked eye. They are most likely caused by interference between the display and the camera.
Tested using Arduino IDE 1.8.19 and Espressif ESP32-BOX-S3-3
This project is a demonstration/experiment so do not take it too seriously. It is based on ESP32-S3-Box-MIDI and adds a web page with HMTL5 sliders for 14 bit CC modulation and volume.
This is a simple example of using lvgl to create one slider on the ESP32-S3 Box display. Moving the slider sends MIDI pitch bend messages over USB. When the slider is released, the slider springs back to the center position.
In addition, a web server is included which serves up a web page with two HTML5 sliders. The sliders provide control of 14 bit MIDI CC for modulation and volume. When the web page is displayed on a tablet, the touch resolution determines the number of unique values. On an iPad, the sliders when moved slowly provide around 1500 unique values. This is substantially better control than 7 bit CC controls which provide 128 unique values.
The web page sends the slider position over a web socket back to the ESP32-S3. The ESP32-S3 converts the slider name and position to 14-bit MIDI CC output on its USB port.
WiFiManager is used to enter the SSID and pass phrase so the first time the ESP32 box runs, be sure to use a phone or tablet to connect to the access point named "HiResCC". When the WiFi Configuration screen appears enter the WiFi SSID and pass phrase for your WiFi network. This only needs to be done once. After this is done, use a tablet (or other device) web browser to connect to "http://hirescc.local" without the double quotes. This web pages shows the HTML5 sliders for modulation and volume.
The following is a screen shot taken from an iPhone running Safari.
Install the following libraries using the Arduino IDE Library manager.
- "ESP32_IO_Expander" by espressif
- "ESP32_Display_Panel" by espressif
- "lvgl" by kisvegabor,embeddedt,pete-pjb Version 8.4.0
- "WebSockets" by Markus Sattler
- "ArduinoJson" by Benoit Blanchon
- "WiFiManager" by tablatronix
The ESP_Panel and lvgl configuration files are set for ESP32-S3 Box 3 and lvgl version 8.4.0.
