This is another small and quick project. My home is quite loaded with technology. The basic is a PLC based controller for the whole electric grid, lightning and similair. More on that in another post ( coming – I am re-publishing alot of stuff ).

The old LED stripes

I do have a few lightning effects also. These are made with NeoPixels LED stripes with addressable RGB LEDs ( WS2812 ). One of them is the hallway mirror, see below.

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The finnished mirror decorations

This one has a 12V DC transformer, an Arduino and a custom shield ( veroboard ) behind the mirror for controlling the RGB LED strip. On three places I have a similar set-up and of course this was considered “temporary”. But as with all temporary fixes it easily gets permanent.

The lighting effect is hardcoded. When turned on it first cycles red, green and blue. Then a rainbow effect that flows around. Finally every LED in sequence turns white. After that it dims during the period of a few hours to off.

The New Version

The new version is based on the NodeMCU DevKit. This is a small board with a USB controller, regulator, flash and a ESP8266 WiFi ship. The firmware in it has a LUA interpreter.

PCB of NodeMCU

PCB of NodeMCU

Pretty cool little building block. It is extremely easy to make a little web server that presents information, and interacts to interactions with the web browser.

LUA Code for a web server

LUA Code for a web server

However the NodeMCU can’t drive the RGB LED strip on it’s own. It do not have enough power to drive 5m of LEDS ( about 144 – 300 depending on version ). So we need additional circuits. Not much, but still.

Sunday I cocked up a small adapter board that contains a 5A 5V switched mode regulator, the recommended 1000µF reservoir capacitors, and a series resistor on the data out. For measure I also added a few LEDs showing status.

Schematic for NodeMCU Adapter

Schematic for NodeMCU Adapter

Not much to show, but still does the job.

The PCB is also fairly simple, and has the same size as the NodeMCU itself. The 2 white blocks that takes up a fair amount of space is Wago 2061 type of push-in connectors. Takes 0.5mm2 to 1.5mm2 and is super high quality. No more old-school screw terminal blocks … yuck!

PCB for NodeMCU Adapter

PCB for NodeMCU Adapter

Stay tuned for evaluation of the PCB itself and software …