State Button for the Makerspace Bonn

A physical button for our makerspace that changes the publicly available opening information. LED indicators show the current space state and connection status.

Features

• Physical Button: Press to toggle space open/closed state
• LED Strip Status: 16 NeoPixel LEDs showing space state (green = open, red = closed)
• Status LEDs:
  • LED 0 (first): WiFi status - blinks yellow when connecting, solid yellow on error, follows state when connected
  • LED 1 (second): MQTT status - blinks yellow when disconnected, follows state when connected
• Robust Connectivity:
  • WiFi reconnection with timeout (30s) and retries (3 attempts)
  • MQTT reconnection with exponential backoff (5s to 60s)
• Watchdog: 42s timeout to recover from hangs

Hardware

• ESP32 (WROOM)
• WS2812B NeoPixel LED strip (16 LEDs)
• Physical button
• Status LEDs (optional GPIO LEDs)

Pin Configuration

Component	GPIO Pin
NeoPixel Strip	5
Button	9
Big Light LED	6
Button Light LED	3
Internal LED	4

Software Setup

ESP32

1. Install MicroPython: https://micropython.org/download/ESP32_GENERIC/
2. Flash the firmware to your ESP32

IDE (PyCharm recommended)

1. Install MicroPython Tools plugin: https://plugins.jetbrains.com/plugin/26227-micropython-tools
2. Create run configuration for your ESP32

Stubs for IDE Support

https://micropython-stubs.readthedocs.io/en/main/24_pycharm.html

Configuration

Create a secrets.py file in src/ (see secrets_example.py):

mqtt_server = 'mqtt.example.com'
mqtt_user = 'username'
mqtt_pass = 'password'

# API key for authenticating state changes to status.makerspacebonn.de
API_key = 'your-api-key'

# Dictionary of known WiFi networks to connect to
wifi_access = {
    'MyWiFi': 'wifi-password',
    'BackupWiFi': 'backup-password',
}

Architecture

src/
├── main.py           # Main loop and initialization
├── mqtt_service.py   # MQTT client with reconnection logic
├── wifi_manager.py   # WiFi management with reconnection
├── state_led.py      # Status LED control (ignore/error/blinking)
├── state_manager.py  # Space state management (API calls to status.makerspacebonn.de)
├── button_handler.py # Button debouncing and cooldown
├── secrets.py        # Configuration (not in repo)
└── lib/
    ├── trickLED.py   # NeoPixel animation library
    ├── animations.py # LED animation patterns
    └── generators.py # Animation generators

References

• Makerspace Bonn Infocenter

Mentions

Inspired by the project from https://gitlab.com/jhaand/hacker-hotel-space-state/