Posts Tagged ‘Arduino’

I’m not really any further with any projects to speak of but it feels good to get some personal coding done. This weekend I’ve been playing around with the RFu-328 modules with SRF from Ciseco. I’ve been trying to get ChibiOS/RT running on them as I think it’ll be great to have a small footprint RTOS which runs on 8 bit micros. Task switching and sleeping during idle will do great things for my wireless nodes. So far I have the basic RTOS running with a thread for processing serial LLAP activity and then a semaphore to signal another to process the data received if it is all in order. Currently I am trying to move from the nodes sending data periodically to being able to be polled by the master. This will help prevent collisions as well as stop me from having to update the firmware on the nodes if I make changes to the system. So for now I’m trying to implement Pinata so I can control all the pins on an Arduino compatible unit. I’m not quite there yet but it’s a good start for a weekend. Code, as always, available on my github.

To get this going I’ve gone back and updated my EVE-node application with all the things I’ve learnt from doing the raspberry pi application at work. This application is nowhere near ready for everday use but if I keep cracking on it will be really useful very soon.

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…