28 April 2015

Raspberry pi + ola server + art-net + spi output + WS2801 leds

I am running my leds on my raspberry pi now after using a lot the FastLED library on my arduino, which is fantastic by the way.
Here's how to setup the rpi :

Donwload latest ola image from http://dl.openlighting.org/
Write it on a SD card
Start your rpi with this SD card
login : pi / password : openlighting

sudo raspi-config

Enable SPI in advanced options + overclock to turbo

sudo apt-get update

sudo apt-get upgrade

sudo reboot

add the following to /etc/udev/rules.d/99-spi.rulesSUBSYSTEM=="spidev", MODE="0666"

write and run this script :
for pin in 17 21; do
  echo $pin > /sys/class/gpio/export;
  chmod a+w /sys/class/gpio/gpio${pin}/value;
  chmod a+w /sys/class/gpio/gpio${pin}/direction;
done

sudo reboot


To config your leds :
1. Go to http://192.168.0.XXX:9090/ola.html and click 'STOP OLA'
2. Open file /var/lib/ola/conf/ola-spi.conf
In my case, a string of 25 pixels is

base_uid = 7a70:00000100                                                                                                                                    
device_prefix = spidev
enabled = true
spidev0.0-0-dmx-address = 1
spidev0.0-0-pixel-count = 25
spidev0.0-0-personality = 1
spidev0.0-backend = software
spidev0.0-ports = 1
spidev0.0-spi-speed = 1000000

Go to OLA admin :  http://192.168.0.XXX:9090/ola.html

Click add universe 

Universe ID = 1
Universe name = 1
Choose artnet as input
Choose SPI as output
save

You should be ready to go, now pick a software that sends data over artnet, like Glediator or Jinx!


Sources :

https://wiki.openlighting.org/index.php/OLA_LED_Pixels
https://wiki.openlighting.org/index.php/OLA_Device_Specific_Configuration#SPI
http://luisgg79.blogspot.be/2014/03/ola-raspberry-pi-led-ws2810-artnet.html
http://grechi.it/blog/2013/11/02/blem-progetto-di-matrice-led-controllata-da-un-raspberry-pi/

I have also a pinterest board where I put stuff for inspiration :
https://www.pinterest.com/pimousse/neopixel/

Have fun !!!!