Charger Display

This project is a custom-built, WiFi-enabled status display for monitoring two e-bike chargers integrated with Home Assistant. It uses an ESP32 and an 8x8 RGB LED matrix to provide real-time visual feedback.

Hardware

• Microcontroller: ESP32-WROOM-32
• Display: 8x8 WS2812B (NeoPixel) RGB LED matrix
• Audio: Active buzzer module for notifications

Features

• Real-time Status Display: Connects to Home Assistant via WebSocket to get instant updates for two charger sensors.

• Visual States: The 8x8 matrix displays different patterns and colors for various states:

  • Charging
  • Disconnected
  • State Unknown
  • No WiFi Connection
  • No Home Assistant Connection

• Web Interface: A built-in web UI allows for easy monitoring and control from any device on the network.

• REST API: Provides endpoints for status checks, configuration, and system control.

• mDNS Service: Easily access the device using the friendly URL http://charger.local.

• NTP Time Sync: Logs are accurately timestamped using time from an NTP server.

• Audible Alerts: An active buzzer provides sounds for state changes and system events.

• Over-the-Air (OTA) Updates: Supports firmware updates over the WiFi network (currently disabled in the main code).

Installation

1. Clone the repository:

   git clone https://github.com/user/charger_display.git
   cd charger_display

2. Configure Secrets: Rename secrets_template.h to secrets.h and fill in your details:

   • WiFi SSID and password.
   • Home Assistant host, port, and long-lived access token.
   • The entity_ids for your two charger sensors in Home Assistant.

3. Install Dependencies: This project requires the following Arduino libraries. You can install them using the Arduino IDE's Library Manager:

   • Adafruit NeoPixel
   • ArduinoWebsockets
   • ArduinoJson
   • NTPClient

4. Compile and Upload:

   • Open the main/main.ino file in the Arduino IDE or your preferred editor (like VS Code with PlatformIO).
   • Select your ESP32 board from the board manager.
   • Select the correct COM port.
   • Click "Upload" to flash the firmware to the device.

Web Interface

The device hosts a comprehensive web interface accessible at http://charger.local.

The UI provides:

• A live view of the 8x8 LED matrix display.
• System status including uptime, IP address, and connection status.
• Live logs from the device.
• Controls to manually set sensor states and adjust display brightness.

REST API

The device offers a simple REST API for integration and control.

• GET /status Returns a JSON object with detailed system status, including uptime, sensor states, logs, and a representation of the current display matrix.

• GET /boot or POST /boot Reboots the ESP32 module.

• GET /config/display_brightness/${val} Sets the display brightness. ${val} should be an integer between 0 and 255. Example: http://charger.local/config/display_brightness/50

• GET /config/update_state/${bike_id}/${val} Manually overrides the state of a charger sensor.

  • ${bike_id}: 1 or 2
  • ${val}: A string like charging, disconnected, or unknown. Example: http://charger.local/config/update_state/1/charging