Project Details

A dedicated, distraction-free ESP32 device for managing a personal book collection. No phone. No cloud. No notifications.

Tracks read books, manages a TBR queue, logs reading progress, and will eventually generate recommendations, all stored locally in flash.

Hardware

Phase 1 target: ESP32-2432S028 ("Cheap Yellow Display")
ESP32-WROOM-32 · 2.8" ILI9341 320×240 TFT · XPT2046 resistive touch · micro-SD · RGB LED · LDR, one $12 board

Also prototyping: GC9A01 round 240×240 SPI display on bare ESP32 modules.

Non-obvious CYD gotchas (documented for posterity):

• Display (HSPI) and touch (VSPI) are on separate SPI buses, TFT_eSPI breaks, use LovyanGFX
• GPIO 21 must be HIGH before display.init() or backlight stays off
• XPT2046 touch axes are swapped and inverted vs. display, raw X → screen Y, raw Y → screen X, vertical axis flipped
• ILI9341 needs rgb_order = true or red/blue are swapped
• Board revision roulette: v1/v2 = ILI9341, v3 = ST7789

Firmware Stack

• Framework: Arduino via PlatformIO
• Display: LovyanGFX ^1.1.16
• Storage: LittleFS (no SD needed for v1)
• WiFi: WiFiManager captive portal, no hardcoded credentials
• Books API: Google Books OAuth device flow (QR code on screen → auth on phone) + OpenLibrary fallback
• OTA: ArduinoOTA over local WiFi

Local-first Data Model

  /books.json      - title, author, status, date read
  /progress.json   - active reading sessions
  /settings.json   - calibration, tokens, prefs
  

Everything lives in flash. No account required. No sync.

Roadmap