Flipdot-display/src/esp32

ESP32: controller

PlatformIO environments: esp32 (OTA) and esp32_usb (USB)

The ESP32 decides what is shown on the display. It never touches the panel itself. The BROSE9323 driver is built with -D ESPSERIAL, so every GFX call is sent over Serial (115200 baud) to the Nano.

Files

File	Contents
main.cpp	setup, OTA, clock / power logic, Home Assistant callbacks
libs.h	includes and global objects (display, MQTT, WiFi, pins, timezone)
bitmaps.h	1-bit bitmaps (Pikachu, thought bubble, Nintendo logo, ...)
secrets.example.h	template for secrets.h (WiFi and MQTT credentials, gitignored)

Features

• OTA updates through ArduinoOTA. Hostname: FlipDotDisplay.
• OTA panic window: after a crash or watchdog reset, the ESP32 runs only the OTA handler for 15 seconds before it starts the main code. A firmware that crashes on boot can still be replaced over the air.
• NTP time with timezone CET-1CEST,M3.5.0,M10.5.0/3 (Europe/Amsterdam).
• Home Assistant through MQTT (home-assistant-integration library) with two switches:
  • FlipDotDisplayClock: clock on, or the Nintendo logo when off
  • FlipDotDisplayPower: turns the display off through the relay
• Relay on GPIO 13 switches the power for both the panels and the Nano. LOW turns it on. After switching on, the ESP waits 3 s so the Nano can boot before frames are sent.
• Status LED (built-in) blinks fast when WiFi is down and slowly when connected. It is off at night or when the display is powered off.

Schedule

Time	Display
07:00 – 17:00	Pikachu and the clock, updated every minute
17:00 – 22:00	Yawning Pikachu and the clock
22:00 – 23:30	Clock drawn only on the quarter hour; power is off in between
night	Screen cleared, power off

Adding bitmaps

Convert an image with image2cpp to "Arduino code", horizontal, 1 bit per pixel. Paste the array into bitmaps.h and draw it with display.drawBitmap(x, y, bitmap, w, h, 1). The display is 84 × 19 pixels.