Arduino firmware for controlling Nixie tube displays using Momento Topics for real-time updates.

This project provides Arduino code to drive Nixie tube displays with real-time data from Momento Topics. The Arduino connects to WiFi, authenticates with an API endpoint to get a token, and then subscribes to a Momento topic to receive updates that are displayed on the Nixie tubes.

• Arduino Uno r4 board with WiFi capability (using WiFiS3 library)
• Nixie tube display modules (EasyNixie)

• OUT_EN: Arduino pin 3 to OUT_EN
• SHCP: Arduino pin 2 to SHCP
• STCP: Arduino pin 6 to STCP
• DSIN: Arduino pin 7 to DSIN

• EasyNixie library
• WiFiS3 library
• ArduinoJson library

Copy the creds.h.template file to creds.h and update with your credentials:

#define WIFI_SSID "your-wifi-ssid" #define WIFI_PASS "your-wifi-password" char tokenEndpoint[] = "your-token-endpoint"; char momentoTopicEndpoint[] = "api.cache.cell-us-east-1-1.prod.a.momentohq.com";

Note: The creds.h file is included in .gitignore to prevent accidentally committing sensitive information.

The code:

1. Connects to WiFi using the provided credentials
2. Obtains an authentication token from the specified endpoint
3. Subscribes to a Momento topic for real-time updates
4. Processes incoming JSON messages and displays the values on Nixie tubes
5. Supports color control for RGB Nixie tubes
6. Uses non-blocking HTTP client implementation for better responsiveness

The expected JSON message format from the Momento topic:

{ "value": "123456", // The numeric value to display (zero-padded) "color": 1 // Color code for RGB Nixie tubes }

1. Install the required libraries in your Arduino IDE
2. Configure your credentials in the creds.h file
3. Upload the sketch to your Arduino board
4. The Nixie tubes will display numeric values received via the Momento topic

The code includes:

• Non-blocking HTTP client implementation
• JSON parsing for Momento topic messages
• LED status indicator (blinks to show the system is running)
• Error handling for network and API issues