Skip to content

Firmware

Building from source

Prerequisites

Build steps

  1. Open the RC_TOOLBOX folder in VS Code
  2. PlatformIO will automatically download dependencies (ESP32 toolchain, LVGL, TFT_eSPI, etc.)
  3. Click Build (✓ checkmark) in the PlatformIO toolbar

Upload to device

  1. Connect your ESP32-S3 via USB
  2. Click Upload (→ arrow) in the PlatformIO toolbar
  3. Wait for the upload to complete
  4. The device will reboot automatically

Alternatively, use the terminal:

pio run --target upload

Monitor serial output

To see debug messages:

pio device monitor

Or click the Serial Monitor icon in PlatformIO.

Pre-built binaries

Pre-built firmware is available in the binaries/ folder:

File Description
firmware.bin ESP32-S3 firmware

Flashing with esptool

If you don't want to build from source, flash the pre-built binary:

pip install esptool
esptool.py --chip esp32s3 --port /dev/ttyUSB0 write_flash 0x10000 binaries/firmware.bin

Replace /dev/ttyUSB0 with your serial port: - macOS: /dev/cu.usbmodem* or /dev/cu.SLAB_USBtoUART - Windows: COM3 (check Device Manager) - Linux: /dev/ttyUSB0 or /dev/ttyACM0

macOS Simulator

For GUI development without hardware, a macOS simulator is included:

./simulator/build_sim.sh      # Release build
./simulator/build_sim_debug.sh  # Debug build

Pre-built simulator binaries are in binaries/: - lvgl_simulator_macOS – Release - lvgl_simulator_macOS_debug – Debug

Run the simulator:

./binaries/lvgl_simulator_macOS

Touch calibration

If touch input is offset, run the calibration environment:

  1. Edit platformio.ini by switching from the default environment to the touch environment:
[platformio]
; default_envs = esp32-s3-devkitc-1
; src_dir = src
default_envs = touch-calibration
src_dir = touch_calibration
  1. Build and upload
  2. Follow on-screen instructions to tap calibration points
  3. Note the calibration values shown on screen

  4. Update src/main.cpp with your calibration data: cpp uint16_t calData[5] = {403, 3387, 375, 3250, 7}; // Your values tft.setTouch(calData);

  5. Switch back to main environment and re-upload