Node.js code for controllig WS2801 and LPD8806 LED stripes via SPI.

• Overview on LED strips http://nut-bolt.nl/2012/rgb-led-strips/
• The LPD8806 protocol explained https://github.com/adafruit/LPD8806/blob/master/LPD8806.cpp
• WS2801 datasheet http://www.adafruit.com/datasheets/WS2801.pdf

• Check if your kernel has SPI support at all.
• Make sure your SPI kernel module is loaded. On the Raspberry Pi add a line

spi-bcm2708

to /etc/modules to load it permanently on boot. If you dont want to load the module on every time you boot the system, load it temporarily with sudo modprobe spi-bcm2708.

• Make your SPI device accessible for the user running the node script. If you want the user pi to be able to use the device, setup groups and permissions:

sudo groupadd -f --system spi
sudo adduser pi spi

and create (or edit) an udev rule. The file /etc/udev/rules.d/90-spi.rules should contain the line

SUBSYSTEM=="spidev", GROUP="spi"

Reboot for the changes to take effect.