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December 03, 2014

Arduino controlled RGB strips

   This is a project I started the other day.  It uses an Arduino Uno to control two strips of RGB LEDs.  The Arduino board belongs to Xiphos and he had picked it up a year or two ago for a project that didn't end up working as advertized.  The Arduino has been sitting idle since.  I decided to I wanted to made an LED controller to replace the one currently in use under my bench.  There are two problems with the existing controller.  One, it can only switch about 10 watts/channel and I cannot drive all my LEDs from a single source.  And two, the PWM is 100 Hz, which is too slow and causes a noticeable strobe effect when the LEDs are the only light source.  I knew the Arduino had PWM channels and I figured they should update faster than 100 Hz.
   Turns out the Arduino was much easier to get up and working than I thought it would be.  In no time I had a PWM dimmer test running.  From my days working at DigiCon (now non-existent) I had a bunch of IFR3710 MOSFETs.  These had been cut off old hardware that was going to be thrown away, and were used in an H bridge to drive a large solenoid.  They are pretty beefy devices and according to the data sheet should be able to switch around 500 watts at 12 VDC.  I have around 20 and have been sitting in a bin for many years.  It was time to put them to work.  I wired the PWM channels to the FETs and was in no time able to control two RGB LED strips.  To check for heat dissipation I connected several LED strips to a single FET and set the duty cycle to 50% (a lot of switching).  It didn't change temperature at all, even pushing more then 30 watts.
   When I showed the setup to Xiphos his eyes lit up.  He had all kinds ideas about what could be done with the setup.
   Xiphos has completed more of his boat.  It has three layers to represent the three decks of the ship, all of which contain 1x1" grid lines for role-playing.  The main mast has been installed and two more are to be added.  The top most deck isn't on the model at the moment so glue can dry, but very nice work Xiphos!
   Yesterday marked December 1st, and the day I typically switch to my snow themed site.  The snow behind the logo was designed back in early 2007 and at the time the browers and computers were so slow I had to limit the snowfall to 50 flakes with a slow update rate.  I've more than double both and it is no longer having an impact on CPU loading.  But then my computer is a lot faster and browers have changed a lot since then.  Anyway, I figured with the amount of snow we have been getting it was only fitting to have my site do the same.

December 01, 2014

I/O Shild of Odroid Dead

   So the work on the solar powered web server has been on hold for a couple of weeks now.  While busy with other projects the main problem is some doesn't work... again.  After some investigation today I'm fairly convinced the Atmel chip on the I/O Shield is dead.  Unlike how I killed the Odroid proper, I don't have a clue how I killed this device.  The chip fails to communicate and runs quite hot.  I have a parts order coming up so I think I'm going to try ordering a replacement CPU.  I should have the tool necessary to replace it and we'll see if that helps. 
   Not that way I like to start December, one of my favorite months.  But December is sure to stay cold, bring more snow, and I'm will be more agreeable soon.
 

November 30, 2014

Updates for Large Data

   Operation Lux has been running since August acquiring light data.  In fact, it has acquired so much that the script that drove the graphs could no longer analyses it all before timing out.  So over the weekend I have been breaking up one massive data file into individual files grouped by day.  This allows the chart to load only the data needed.  That all seems to be working and viewers can once again scroll through the light data.
   Our group battles a Hydra in an effort to prove to the island's Orks we are worthy of their respect.
   Our annual Black Friday leftovers gathering today.  We had a fair number of people but really no leftovers.  Instead we bought food and cooked it, spending all of the afternoon and evening eating.
   A few weeks ago the household worked on cleaning up the garage so the a car could be parked inside.  As part of the process we put up an other shelve to hold wood.  Here I am grinding off some screw heads that stuck through the wood after mounting.
   While I had a full day to work on projects, I spent a good deal of time in front of the computer.  Our laptop, Pluvius, needed to be reformatted and setup.  It's a long boring process.  I switched from Linux Mint back to Ubuntu, mainly because my only problem with Ubuntu is Unity and once you get rid of that everything is fine.
   Pictured are Zach and James sampling alcohol soaked fruit from a concoction they made.