Raadhuis Xmas3 Arduino

Arduino code to control the Xmas tree (hence the name) RGB LEDs in Lieshout, the Netherlands.

What?

This code runs on the arduino connected to the tree, enabling control of the lights via TCP/IP. The web will handle user requests and use this to set and get colors. The xmas3 protocol is pretty simple:

• Open a connection to the arduino
• Send a byte 'g', and the tree returns three bytes corresponding to the RGB values of the current color
• Send four bytes to set a new color, the last three bytes correspond to the RGB values.

A color is set by updating the duty cycle of three (R, G, B) PWM pins. Those PWM signals are brought to 12 volt level using NPN-transistors and then amplified to be able to source a decent amount of current.

Testing

Since we don't lack confidence, there are no tests.

Get a color:

echo -e 'g' | netcat $host $port

Set a color:

echo -e 's\xff\x00\xff' | netcat $host $port

Artists rendering of the hardware setup:

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