Archive for January, 2013

Ambilight build

Posted: January 28, 2013 in Ambilight
Tags: , , ,

I have started a new little project this weekend which I have had in the back of my mind for a while and never managed to start. I am building an Ambilight system for my HTPC as I think it’s pretty cool and is a nice excuse for another small microcontroller project. There are many projects like this out there on the web but as always I never do things exactly the same as everyone else. I guess the Adalight project is the closest thing to what I’m building but the RGB LED strip I got uses the WS2811 IC instead of the WS2801. This chip is pretty amazing as it puts the 3 LEDs and the controller all on the same piece of silicone and it is driven by only 1 line from the controller.

So I obviously couldn’t use the library available on github from Adafruit. The library recommended by the seller was FastSPI. This was pretty easy to get going with the demo code except that you have to declare  your device as TM1804 and not WS2801. Other than that the rest of the system just uses Boblight in XBMC and a controller connected to USB reading and setting the RGB values to the LEDS.

I’ve decided to do all my testing on an Arduino Uno I have lying around and then port the code to a smaller board once it is all working (probably the JeeNode).  The code was pretty easy and I’ll post links once I’ve uploaded it somewhere but the difficult part was really understanding and configuring boblightd. Boblightd has a complicated configuration file but I got started with another file which I got from here with a handy real word description of things here.

Basically the way things worked out with my particular strip on my particular monitor I have 32 LEDs running along the top 1 in each of the top corners and 13 running along each side but not all the way to the bottom. So therefore I have to configure 60 LEDs but not across the full height of the screen. So that gives a situation as bellow:

LED layout
So with the horizontal and vertical scans starting at zero in the top left of the diagram above and my LED strip starting with LED0 just above the bottom right I configured my boblight.conf file for my particular system. I tested this out using the boblight-constant application and things seemed fine but I unfortunately don’t have a 5V power supply which I can use for this project long term. I think 5V 2A will be sufficient. So for now that’s as all I have but I will post again with a video when it’s done. For now some pics…





EE Times University

Posted: January 16, 2013 in Uncategorized

I’ve been working on the EE Times University course Wireless for Miniaturized Consumer Electronics & Mobile Products this week. It has been good so far. The lectures and slides are archived so you can catch up if you have missed the last 2 days. The lecturer has been pretty good but the coordinator is pretty annoying. Have a look if you interested.