Uploaded January 2026 | Updated September 2026, 9 hours ago
Ever noticed that flickering LEDs all start pulsing in sync when you power them on together?
In this quick TerrainTronics tech-support video, I show how to drive up to eight LEDs, all flickering independently and randomly, with zero coding required.
Using a Wemos D1 Mini and the Harlech Castle board, you can install a pre-built lighting program directly over USB from a web browser and control multiple lighting modes with a single knob — perfect for fireplaces, torches, windows, and ambient terrain lighting.
What’s covered:
- Why flicker LEDs sync up
- How to make each LED flicker independently
- Installing firmware directly from your browser
- Multiple lighting modes using a single potentiometer
- Easy hacks for adding a master on/off switch
🔗 Useful Links
🌐 TerrainTronics products:
terraintronics.com
⬇️ TerrainTronics Direct browser-based uploader for Wemos D1 Mini:
downloads.terraintronics.com
🧰 Tools, LEDs, and parts (Amazon Affiliate):
amazon.com/shop/terrain-tronics
💬 Join the TerrainTronics Discord:
links.terraintronics.com/discord
If you’ve got a terrain lighting problem you want solved, drop it in Discord — it might turn into the next video!
Tiny boards. Big effects.
ChatGPT was used to generate the thumbnail using a photograph. ChatGPT was also used in the debugging process with the code used.
Ever noticed that flickering LEDs all start pulsing in sync when you power them on together?
In this quick TerrainTronics tech-support video, I show how to drive up to eight LEDs, all flickering independently and randomly, with zero coding required.
Using a Wemos D1 Mini and the Harlech Castle board, you can install a pre-built lighting program directly over USB from a web browser and control multiple lighting modes with a single knob — perfect for fireplaces, torches, windows, and ambient terrain lighting.
What’s covered:
- Why flicker LEDs sync up
- How to make each LED flicker independently
- Installing firmware directly from your browser
- Multiple lighting modes using a single potentiometer
- Easy hacks for adding a master on/off switch
🔗 Useful Links
🌐 TerrainTronics products:
terraintronics.com
⬇️ TerrainTronics Direct browser-based uploader for Wemos D1 Mini:
downloads.terraintronics.com
🧰 Tools, LEDs, and parts (Amazon Affiliate):
amazon.com/shop/terrain-tronics
💬 Join the TerrainTronics Discord:
links.terraintronics.com/discord
If you’ve got a terrain lighting problem you want solved, drop it in Discord — it might turn into the next video!
Tiny boards. Big effects.
ChatGPT was used to generate the thumbnail using a photograph. ChatGPT was also used in the debugging process with the code used.
