Thursday, February 20, 2014

Pretty little lights

I've been busy investigating LED technology and I've learned a few things like many cheap LED bulbs don't work well in a table lamp. I've also learned about bulb type and shapes, color temperature, color rendering index (CRI), that LEDs fade over time and LED WAF. I've found a few bulbs that work (so far, let's see how long these things last). I am worried about cheap bulbs and bulb life. If I understand things correctly, my LED bulbs will slowly fade over time, cheap bulbs more so as they push the components past design recommendations. I've already seen CFL bulbs die a smokey and smelly death. I'm hoping that won't happen with LED bulbs.
Since LEDs are small, it might be time to rethink the light fixtures. I've seen a number of interesting lamp/light designs. So with that thought I picked up a Adafruit NeoPixel RGB LED Strip. I plan on using them on the Dollhouse. It should be interesting to see how they get used an what I can do with them. I intend to control them with the chipKit Pi from Pytomation on the Raspberry Pi. If I understand the interface correctly I'll need to setup the ChipKit board to have 8MHz SPI setup. More on that later.

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Tuesday, February 18, 2014

Raspberry PI, topped with a chipKit Pi

In a previous posting I hinted about using the chipKit Pi instead of the Arduino Uno with my Raspberry Pi and the Z-Wave board. The chipKit board fits nicely on the Raspberry Pi and gives me the equivalent of a serially connected Arduino on the IO header of the Pi. Using the chipKit_Pi with Pytomation instead of the Arduino will give me a nice platform to interface to my Dollhouse. In addition the Z-Wave interface makes for a nice demonstration of technology that normal consumers can buy. Hopefully I'll be able to do a few preview demonstrations at IXR before TCF 2015. I'll definitely need a few more Z-Wave devices before then.

My choice of hardware has confused a few people. They ask why one or the other. A lot of what I do involves the internet. I love the Arduino, it's inexpensive, small, supports plenty of libraries and easy to use. But I don't want to try and squeeze IP support into such a small processor. Team that up with a Raspberry Pi instead of an Ethernet shield and the ease of programming provided by Linux and the Pi makes the extra cost more than worth it. Now choosing between an Arduino Uno and a chipKit Uno32 comes down to more what I have on hand more than the cost of the 2 boards (Uno32 is more expensive). The chipKit does edge out the Arduino in CPU and system resources. So when it comes time to decide, it is the right tool for the job. :-).

Oh and that tight timing I mentioned above, that would be the 60 LED/meter strip I'll be working with. At the moment I'm not sure how it will be used in the Dollhouse but I know it will.