For more info, see the Wemos website.
I used the basic Arduino environment with the Arduino esp8266 extensions to develop the code. There is lots of information on the internet on how to set that up, so I'm not going to put that in this posting.
What I wanted to get working is a setup with the following features:
In order to get this working, I have used a number of different libraries that are available.
This library makes it very easy to configure the wifi. When starting the first time, the esp will be configured as an accesspoint. When connnected to the accesspoint you can configure the wifi settings of the network the esp should connect to. On the next boot, the esp will automatically try to connect to the stored accesspoint.
Adafruit Neopixel library
This library makes it very easy to control different kinds of daisychained RGB leds. The PL9823's I used are nicely supported by this library.
This is part of the default library. Again, this library makes it very simple to serve up a webpage from the esp. I use this to serve 1 page, which contains all code that should run in the webbrowser.
This library is an easy way to make a websocket connection between the webbrowser and the esp to exchange data.
The design I ended up using for the code splits the code up in two parts:
The core communication between the webbrowser and the esp is done through a websocket connection. This allows for quick exchange of data between the browser and the esp. In the code this is used to update the browser for the current status of the leds, current select color, pattern etc.
Next to handling the websocket and webpage requests, the esp also handles the updates of the leds. I implemented a couple of patterns, just to see if I could get the whole setup working. And it seems to do what I want.
The code is available on github, see the link below. Please note that it isn't cleaned up or anything and could be more robust and readable. But it should make for a quick start for anyone wanting to try something like this.
Below are two video's of the tree with the current version of the software. First is a kind of star pattern with the leds fading in and out at random positions. As you
can hear, Maika (my cat) doesn't agree with me working on the code for the tree ;)
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The second is a dual loop pattern in the tree.
The last video is the webinterface through which the tree can be controlled. It
shows the effects present in the code at the time of recording, and some other
settings that can be changed.
Total cost of this project (excluding the hours coding and discovering how to work
with the esp8266):