Speeduino ECU Display using ESP32-C3 and ILI9488 3.5" TFT

Summary

This project creates a digital dashboard display for Speeduino ECU using ESP32-C3 microcontroller and a 3.5 inch TFT LCD display with ILI9488 driver. The display shows real-time engine data from the Speeduino ECU including RPM, AFR, TPS, advance timing, MAP, and other sensor readings. The configuration has been optimized for ESP32-C3 pin mapping with reliable serial communication to the ECU.

Build Status: ✅ SUCCESS

Project has been successfully compiled with the latest pin configuration.

Pin Configuration

TFT Display Pin Mapping

Pin mapping used for ILI9488 TFT display:

TFT_MISO = 5   // SPI MISO
TFT_MOSI = 6   // SPI MOSI  
TFT_SCLK = 4   // SPI Clock
TFT_CS   = 7   // Chip Select
TFT_DC   = 8   // Data/Command
TFT_RST  = 10  // Reset

Serial Communication to Speeduino ECU

Pin mapping used for UART communication to Speeduino ECU:

RX_PIN   = 20  // Serial RX (connect to Speeduino TX)
TX_PIN   = 21  // Serial TX (connect to Speeduino RX)
BAUD_RATE = 115200  // Communication speed

Note: Uses Serial1 (hardware UART) for reliable communication with Speeduino ECU.

What Has Been Configured

1. TFT_eSPI Library v2.5.43 - Added to dependencies in platformio.ini

2. ILI9488 Driver - Configured for 3.5 inch display with 320x480 resolution

3. Pin Configuration - Pin mapping optimized for ESP32-C3

4. Build Flags - All required definitions added to platformio.ini:

   • ILI9488_DRIVER=1
   • Pin definitions (MISO=5, MOSI=6, SCLK=4, CS=7, DC=8, RST=10)
   • Font loading configurations
   • SPI frequency settings (20MHz for stable operation)

5. Font System - Changed from custom fonts to built-in TFT_eSPI fonts:

   • Font 2 (16px height) for small text
   • Font 4 (26px height) for large text

6. Function Declarations - Added required function declarations

Modified Files

1. platformio.ini - Added dependencies and build flags
2. src/main.cpp - Fixed font loading and function declarations

Wiring Connections

ILI9488 Display to ESP32-C3

Connect the ILI9488 display to ESP32-C3 according to the pin mapping above:

ILI9488 Display    ESP32-C3
---------------    --------
VCC               3.3V
GND               GND
CS                GPIO 7
RESET/RST         GPIO 10
DC/RS             GPIO 8
SDI/MOSI          GPIO 6
SCK/CLK           GPIO 4
LED/BL            3.3V (direct connection without control)
SDO/MISO          GPIO 5

Speeduino ECU to ESP32-C3

Connect the Speeduino ECU serial pins to ESP32-C3:

Speeduino ECU     ESP32-C3
-------------     --------
TX (Serial Out)   GPIO 20 (RX)
RX (Serial In)    GPIO 21 (TX)
GND               GND

Note:

• Backlight (LED/BL) is connected directly to 3.3V to simplify wiring and ensure the display is always on. No backlight control pin is used in this implementation.
• Serial communication uses 115200 baud rate, 8 data bits, no parity, 1 stop bit (8N1)
• Make sure to connect GND between all devices for proper communication

Build Steps

1. Install dependencies:

   python3 -m platformio lib install

2. Build project:

   python3 -m platformio run

3. Upload to ESP32-C3:

   python3 -m platformio run --target upload

Important Notes

1. DMA Warning - ESP32-C3 does not yet support DMA for TFT_eSPI, but the library works without DMA.

2. Touch Screen - If the display has touch screen capability, uncomment the TOUCH_CS pin in configuration.

3. SPI Frequency - Configured at 20MHz for optimal performance with ILI9488 and ESP32-C3 stability.

4. Backlight Connection - Display LED/BL is connected directly to 3.3V for simplified wiring. Display will always be on without dynamic brightness control.

5. ESP32-C3 Stability - Specific platform version (6.5.0) and build flags are used for stable operation on ESP32-C3.

Testing

After uploading firmware, the display will show:

• Splash screen with firmware information
• Speedometer interface with various sensor data
• Status buttons and indicators

The project is now ready to use with the ILI9488 3.5 inch display!