Raspberry Pi enabled Christmas Lights from shabaz in the Element14 Raspberry Pi Projects!

This was a fun project to try to make some flashing lights. Of course, it needed to be a bit more complex than that so a Raspberry Pi was used for Internet connectivity, and some analog circuitry was used to generate multiple PWM outputs to drive strings of lamps. Everything can be dimmed or particular patterns selected from any web browser. For a holiday look, the lamps were enclosed in star-shaped laser-cut acrylic. All the steps are detailed here if you wish to build something similar.

The controller board was built in two evenings after work, and the strings of lamps can take a few hours to assemble; so this could be a weekend project.
Even if you’ve already have your holiday lights arranged by now, this post may be useful for the following information:

• Using 555 timers
• Controlling a DAC using the Raspberry Pi
• Controlling hardware using MOSFETs

The source code is also useful if you have other requirements for controlling or retrieving status information from software or hardware using a web browser.
 
The project uses low voltage lighting for safety and hardware PWM to greatly simplify the software. The software is simplified further by utilizing JavaScript as the main programming language; the entire project occupies just three small files….

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