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                          Copyright (c) 2025 nicolas2k

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Driver ILI9486 + XPT2046 for ESP32-WROOM32 LOLIN32 V1.0 (Dual Core)

Firmware to drive a 480x320 ILI9486 LCD with an XPT2046 resistive touch controller on ESP32. Includes diagnostics, text/color tests, and a guided 5-point touch calibration with NVS persistence and optional INI mirroring.

Features

• ILI9486 LCD driver and simple graphics primitives
• XPT2046 touch driver with debounced tap processing
• 5-point calibration (TL, TR, BL, BR, Center)
• Stores calibration in NVS; mirrors to /spiffs/config.ini and prints it
• Optional diagnostics: color bars, TV test pattern, text tests

Hardware reference

• ESP32-WROOM32 LOLIN32 V1.0
  • Product page: https://www.espressif.com/en/producttype/esp32-wroom-32
• Panel: MPI3501 (3.5inch RPi Display), 480x320 pixels
  • Product page: https://www.lcdwiki.com/3.5inch_RPi_Display

Project layout

• main/
  • main.c: entry point, tests and calibration trigger
  • display.*: higher-level drawing and test screens
  • lcd_ili9486.*: LCD panel driver
  • lcd_graphics.*: primitives and text
  • touch.*: touch abstraction
  • touch_xpt2046.*: XPT2046 low-level SPI I/O
  • touch_calibration.*: calibration flow and persistence
  • config_storage.*: NVS persistence helpers
  • spiffs_data/config.ini: startup configuration copied to /spiffs

Build and flash (macOS)

• Install ESP-IDF 5.5.x
• In project root:
• idf.py set-target esp32
• idf.py build
• idf.py -p /dev/tty.usbserial-XXX flash monitor

Configuration (spiffs_data/config.ini)

• [display] screen_width=480, screen_height=320
• force_calibration=1 forces calibration at next boot
• touch_calibration_mode=1 enters guided calibration mode
• After successful calibration:
• [calibration] section is appended with x_min/x_max/y_min/y_max and flags
• touch_calibration_mode is set to 0 and the updated file is printed

Calibration flow

• Tap 5 targets when prompted
• Values are persisted to NVS and mirrored to /spiffs/config.ini
• Device restarts after showing results

Versioning

• Version is defined in main/version.h (e.g., 1.0.0)
• Logged at boot with build date/time

License

• MIT License © 2025 nicolas2k
• See LICENSE for full text
• Optional per-file header: /* SPDX-License-Identifier: MIT */

Roadmap

• Next version: bilingual (FR/EN) transcriptions on-screen and in docs