Hardware¶
Components¶
Microcontroller¶
ESP32-S3 DevKitC-1 (recommended)
- Dual-core Xtensa LX7 @ 240 MHz
- 512 KB SRAM, 8 MB Flash
- USB-C for programming and power
- Built-in RGB NeoPixel LED (GPIO 48)
Other ESP32-S3 boards should work with pin adjustments.
Display¶
2.4" TFT with ILI9341 driver + XPT2046 touch controller
- Resolution: 320 × 240 pixels (landscape mode)
- SPI interface for both display and touch
- 3.3V logic (compatible with ESP32-S3)
These displays are widely available on AliExpress, Amazon, etc. Look for "2.4 inch TFT SPI ILI9341 touch".
Rotary Encoder¶
EC11 rotary encoder with push button
- Rotation for value adjustment and menu navigation
- Push button for selection/confirmation
- Active LOW button (internal pull-up used)
Optional¶
- Servo connectors – Standard 3-pin headers for servo outputs
- Battery voltage divider – For LiPo checker function (ADC input)
Pinout¶
Pin configuration files
Pin assignments are defined in two places:
platformio.ini– Build flags for TFT_eSPI library (display, touch, SD card, NeoPixel)include/pins.h– All other pins (servos, encoder, ADC, I2C, backlight)
If you use different hardware, adjust both files accordingly.
Display & Touch (SPI)¶
| Function | GPIO | Notes |
|---|---|---|
| TFT_MOSI | 11 | SPI data out |
| TFT_MISO | 13 | SPI data in |
| TFT_SCLK | 12 | SPI clock |
| TFT_CS | 10 | TFT chip select |
| TFT_DC | 8 | Data/Command |
| TFT_RST | 9 | Reset |
| TFT_BL | 5 | Backlight PWM |
| TOUCH_CS | 14 | Touch chip select |
| TOUCH_IRQ | 7 | Touch interrupt |
Rotary Encoder¶
| Function | GPIO | Notes |
|---|---|---|
| ENC_CLK | 35 | Encoder output A |
| ENC_DT | 36 | Encoder output B |
| ENC_SW | 37 | Push button (active LOW) |
Servo PWM Outputs¶
| Servo | GPIO |
|---|---|
| Servo 1 | 6 |
| Servo 2 | 15 |
| Servo 3 | 16 |
| Servo 4 | 17 |
| Servo 5 | 18 |
| Servo 6 | 21 |
ADC Inputs (Battery Voltage)¶
| Channel | GPIO | Notes |
|---|---|---|
| ADC 1 | 1 | With voltage divider |
| ADC 2 | 2 | With voltage divider |
| ADC 3 | 3 | With voltage divider |
Other¶
| Function | GPIO | Notes |
|---|---|---|
| NeoPixel | 48 | Built-in RGB LED |
| SD_CS | 4 | SD card (optional) |
| I2C_SDA | 47 | I2C data (used by PN532 NFC) |
| I2C_SCL | 39 | I2C clock (GPIO48 reserved for NeoPixel) |
NFC (PN532, I2C)¶
| Function | GPIO | Notes |
|---|---|---|
| PN532_IRQ | 41 | Data-ready interrupt |
| PN532_RST | 40 | PN532 hardware reset |
| I2C_SDA | 47 | Shared I2C data |
| I2C_SCL | 39 | Shared I2C clock |
PN532 DIP switch settings
Set DIP switches to 1/0 for I2C mode:
- 0/0 = HSU (High Speed UART)
- 1/0 = I2C ← use this
- 0/1 = SPI
I2C pin choice
The ESP32-S3 DevKitC-1 uses GPIO48 for the built-in NeoPixel.
To avoid conflicts, I2C SCL is assigned to GPIO39 (see include/pins.h).
Reserved pins / conflicts
- SPI bus (TFT/Touch only): GPIO11 (MOSI), GPIO12 (SCLK), GPIO13 (MISO)
- SPI chip selects: GPIO10 (TFT_CS), GPIO14 (TOUCH_CS), GPIO4 (SD_CS)
- GPIO48 is reserved for the built-in NeoPixel
- GPIO45/GPIO46 are available but are strapping-related pins (use with care)
Wiring Diagram¶
Connect the display and encoder to the ESP32-S3 according to the pinout table above.
Custom PCB¶
A custom PCB is available for a cleaner build:
PCB design sources and manufacturing outputs live in the repository under the hardware/ folder:
- Board layout:
hardware/RC TOOLBOX.fbrd - Schematic:
hardware/RC TOOLBOX.fsch - Schematic PDF:
hardware/RC TOOLBOX_Schematic_v194.pdf - Gerbers:
hardware/RC TOOLBOX_Gerber_v432.zip
Browse/download here: https://github.com/chiefenne/RC_TOOLBOX/tree/main/hardware