klubhaus-doorbell/boards/uno-r4-wifi

Uno R4 WiFi Doorbell - Quick Start Guide

Overview

This is a simplified doorbell notification system for the Arduino Uno R4 WiFi that displays incoming ntfy.sh messages on the built-in 12x8 LED matrix.

Features

• Connects to WiFi and monitors a ntfy.sh topic
• Displays incoming messages as scrolling text on LED matrix
• Scrolls at 2 columns per second (configurable)
• Auto-silences after 60 seconds of display
• Simple state machine: CONNECTING → IDLE → DISPLAYING → SILENCED

Setup Instructions

1. Configure WiFi Credentials

Edit boards/uno-r4-wifi/uno-r4-wifi.ino:

#define WIFI_SSID "YOUR_WIFI_SSID"
#define WIFI_PASS "YOUR_WIFI_PASSWORD"

2. Configure ntfy.sh Topic

Edit boards/uno-r4-wifi/uno-r4-wifi.ino:

#define NTFY_TOPIC "YOUR_TOPIC_HERE"

Create a free topic at https://ntfy.sh/ (e.g., "my-doorbell-12345")

3. Upload the Sketch

arduino-cli compile --fqbn arduino:renesas_uno:unor4wifi boards/uno-r4-wifi/uno-r4-wifi.ino
arduino-cli upload --fqbn arduino:renesas_uno:unor4wifi -p /dev/ttyACM0 boards/uno-r4-wifi/uno-r4-wifi.ino

4. Test the System

Open a terminal and run the test script:

chmod +x boards/uno-r4-wifi/test_messages.sh
./boards/uno-r4-wifi/test_messages.sh

Or manually send a message:

curl -X POST https://ntfy.sh/YOUR_TOPIC_HERE -d "Hello from ntfy!"

How It Works

State Machine

1. CONNECTING_WIFI - Attempts to connect to WiFi
2. IDLE - Polls ntfy.sh every 5 seconds for new messages
3. DISPLAYING_MESSAGE - Shows scrolling text for 60 seconds
4. SILENCED - Clears matrix for 5 seconds before returning to IDLE

LED Matrix Display

• Text scrolls from right to left across the 12x8 matrix
• Scroll rate: 2 columns per second (500ms per column)
• Characters are 5 pixels wide with 1 pixel spacing
• Only alphanumeric characters (A-Z, 0-9) and spaces are supported

ntfy.sh Integration

• Uses HTTP GET with polling (/json?poll=1)
• Tracks last message ID to avoid duplicates
• Parses JSON response for message body

Pinout Reference (Uno R4 WiFi)

• D0-D13: Standard digital pins
• A0-A5: Analog inputs
• D26/D27: Qwiic (I2C) connector (SCL/SDA)
• LED Matrix: Built-in 12x8 matrix (pins handled internally)

Customization

Adjust Timing

Edit constants in uno-r4-wifi.ino:

#define POLL_INTERVAL_MS 5000      // How often to check for messages
#define DISPLAY_DURATION_MS 60000  // How long to display each message
#define SCROLL_SPEED_MS 500        // Scroll speed (lower = faster)
#define SILENCE_DURATION_MS 5000   // Time between messages

Add More Characters

The font array in drawCharToFrame() can be extended to support additional characters.

Troubleshooting

WiFi Won't Connect

• Check WiFi credentials
• Ensure 2.4GHz network (Uno R4 WiFi doesn't support 5GHz)
• Verify WiFi signal strength

LED Matrix Not Showing Text

• Ensure matrix.begin() is called in setup()
• Check that matrix.loadFrame() is called with valid data
• Verify text contains only supported characters

No Messages Received

• Check ntfy.sh topic name matches exactly
• Ensure the topic is publicly accessible
• Test with curl command manually
• Check serial monitor for error messages

Next Steps

• Add support for more characters in the font
• Implement different message types (Alert, Silence, etc.)
• Add color coding with different LED patterns
• Integrate with the main doorbell codebase