Andrew Que Sites list Photos
Projects Contact
Main
   This is the nearly finished result of my Arduino light controller.  Yesterday and today I put the cleaning touches on the source code, and it now controls all 6 channels (my initial setup only controlled 3 channels via DMX).  I have ordered a part that should allow me to program the blank ATmega328 part, which will allow me to put the controller on it's own board.  Then it gets combine with a 12 volt power supply and handed off to Xiphos for his lighting rig.  I am pleased enough with the results I plan on making a similar setup for my under bench lights.  I am considering using the infrared remote I have to signal an Arduino, which will in turn control the LEDs in my bench setup.  Xiphos and I also talked about making use of some of the other I/O, perhaps to control some strobe lights.  There are a fair number of pins left, so this an option.
   Didn't bike into work because my back tire still isn't holding air.  However I took the bike out this evening for my typical 10 mile loop since I had no time schedule a flat might upset.  The tire held up fine, so it must be a slow leak.  The reason I wanted to do an evening ride was my under shirt that is suppose to wick sweat away from the body so I don't have cold liquid against my skin.  I wanted to give it a test.  While it isn't cold (above freezing) it is humid, and a quick 11 mile run should provide a good test.  I'm not sure how I feel about the garment.  It seems like I felt dryer during the ride.  But when I returned home and pulled the shirt off it was soaked is perspiration.  More data is needed.
   I tried a couple of shots while on the ride.  However there was a fairly steady wind from the west, and the cheep tripod I was using wouldn't hold still enough for the long exposures.  So I only got a couple of pictures. 
Raven

Raven

   Attended a photo exhibit this evening in which our house, Elmwood Park, was featured.  The photographer wanted to capture communal living and put together a set of pictures emphasizing our sci-fi/fantasy/role-playing side.  The speech that accompanied the presentation was about how the title of nerd isn't claimed, but earned, and earned the hard way.  One doesn't become a nerd because they decide to be, it's because they are and have no choice.  It spoke directly to my nerdy little heart.
   Pictured is Raven who attended the showing with me.

December 09, 2014

Xen's Choir Concert

Xen on stage

Xen on stage

   Tonight we attended Xen's choir concert in an over packed auditorium.  We were able to get seats because Xiphos new the person operating lights/sound.  I've discovered my love for music is a bit of a hindrance when it comes to appreciating middle and high school kids singing.  Missed notes were like fingernails on a chalkboard and while I was trying to give every benefit to the singers and nonetheless made a scrunchy face many times throughout the performance.
   Xen was one of 4 young men to in his choir and they sang a solo part together.  While I tried hard I could not pick out Xen's voice from the others, but they harmonized well and were (thankfully) always in pitch.  He gave a good performance.

December 08, 2014

Arduino DMX controller

Xiphos controls RGB strips from his lightboard

Xiphos controls RGB strips from his lightboard

   Today an order of parts arrived.  Included was an RS-485 transceiver.  This will allow the Arduino to receive the DMX-512 signal from a light board.  I found a DMX library for the Arduino and figured after I could receive the DMX signal the rest should be pretty easy.  I was right.  After putting the transceiver on the breadboard and connecting it to the Arduino it was less than a minute before I had control of an LED using the library--everything just worked.  I spent the rest of the night setting up the code to drive the LEDs.  I assigned 4 channels to a single RGB strip.  The 4th selector is a mode select, and I currently have 4 modes: RGB, HSL, strobe, and fade.  RGB mode just sends the levels from channels 1-3 to each of the LED PWMs.  Nothing to that.  HSL was something I had been toying with over the past week and I created a function to translate hue/saturation/lightness to RGB.  This works pretty good.  In strobe mode, I use the first channel to select the color of the strobe effect (hue), the second channel for how long between pulses, and the third channel for the duration of the pulse.  This does allow blinking, but the LEDs don't seem to be fast/bright enough to really good a strobe effect like one can with a Xenon strobe tube.  The last mode is a fade.  It uses the first channel to determine the speed of the fade, the second channel for saturation, and the third for lightness. 
   While the code needs some cleanup, I was surprised at how quickly this all came together.  The Arduino makes these kind of project move very quickly without the the need to really dig into the details of anything.  Having been an embedded programer for over 17 years I am not use to the ease of a project like this.  Things like this usually involve more datasheets, register setup, and a painful learning curve for the tools.
   The only thing I didn't get working right away was a blank Atmel chip.  I picked up the same chip as the Arduino, but didn't realize the Arduino requires the chip be programmed with a bootloader.  I will have to look into getting the chip programmed so the system can be built up as a standalone system.  For now, however, the setup works great and both Xiphos and I are very pleased.