velxio/examples
David Montero Crespo 20bda8e427 docs(examples): add ESP32-CAM + ILI9341 live preview example
First end-user demo of the new ESP32-CAM emulation capability —
shows how to wire an ESP32-CAM to an ILI9341 320×240 SPI TFT,
decode JPEG frames from the emulated webcam with jpg2rgb565()
(built into esp32-camera/conversions, header now exposed by the
Velxio compile template), and render the resulting RGB565 bitmap
to the screen at ~10 fps.

Two sketches in the same example folder:

- esp32-cam-lcd-preview.ino — full demo: decode JPEG → render the
  bitmap (160×120 centered in the TFT) + status bar with fps,
  frame counter, decode-fail counter, live pulse dot.

- esp32-cam-lcd-status.ino — companion that doesn't decode the
  JPEG; instead it shows a status dashboard (frame counter, byte
  histogram, JPEG header hex dump). Useful when the source JPEG
  exceeds the deliverable byte budget and jpg2rgb565 fails on the
  truncation.

diagram.json wires the two parts using velxio-esp32-cam +
wokwi-ili9341 part types over VSPI:
   ILI9341 ↔ ESP32-CAM
   CS ↔ GPIO 15, RST ↔ GPIO 2, D/C ↔ GPIO 14,
   MOSI ↔ GPIO 13, SCK ↔ GPIO 12

libraries.txt lists Adafruit GFX + Adafruit ILI9341. esp_camera.h
and img_converters.h ship with arduino-esp32 — no extra install.

Adds examples/README.md as the index for future demos.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
2026-05-02 22:14:42 -03:00
..
esp32-cam-lcd-preview docs(examples): add ESP32-CAM + ILI9341 live preview example 2026-05-02 22:14:42 -03:00
README.md docs(examples): add ESP32-CAM + ILI9341 live preview example 2026-05-02 22:14:42 -03:00

README.md

Velxio examples

Ready-to-run sketches that exercise specific Velxio features end-to-end. Each subdirectory ships:

  • *.ino — the sketch (paste into Velxio's editor)
  • diagram.json — wiring layout (parts + connections, Wokwi-compatible format)
  • libraries.txt — Arduino libraries to install via Library Manager
  • README.md — wiring picture, run instructions, what to expect

Index

Folder Board Demonstrates
esp32-cam-lcd-preview/ ESP32-CAM + ILI9341 Live webcam preview decoded with jpg2rgb565 and rendered to a 320×240 SPI TFT

Adding a new example

  1. Create a folder named after the demo (e.g. arduino-uno-pong-rgb/).
  2. Drop in the four files above.
  3. Wire diagram.json using the velxio/wokwi part types — see existing examples for naming. Velxio-specific boards use the velxio- prefix (velxio-esp32-cam); generic Wokwi parts use wokwi- (wokwi-ili9341, wokwi-led, etc.).
  4. Add a row to the table above.

If your example needs more than the standard libraries, list every required library in libraries.txt (one per line, # for comments).