Feasible to drive Adafruit Neopixel LED strip?

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Adafruit is kind of scary about controlling their new "Neopixel" 60-led strip due to stringent timing rqts. they write

"to get high density, the controller chip is inside the LED, which is kind of cool, but also means that the chip only uses a single pin for input and a single pin for output. The protocol used is very very timing-specific and can only be controlled by microcontrollers with highly repeatable 100nS timing precision. We have example code for using with the Arduino Uno/Mega microcontroller at 8MHz and 16MHz, but it will not work with the Raspberry Pi, Basic Stamp, NETduino, any other interpreted/virtual machine microprocessor or any processor slower than 8 MHz."

The above is from this page http://adafruit.com/products/1138

So is this controllable using the Teensy 3.0? Seems to me it should be possible to avoid timing problems by masking interrupts. Suggestions?

thanks in advance.
Charlie in Encinitas CA
 
Yes, you can run NeoPixels, but ...

I've had some success running NeoPixels with the Teensy, but I still don't have it perfected and it's been a very frustrating path. The main problem seems to be the 3.3V signaling from the Teensy 3.0/3.1, so I added a level converter I got from SparkFun.com. That almost worked. But the system was still hinkey, so I put the scope on it. The signal I was getting from the Teensy looked perfect, but after it passed through the level converter, I had a wave form that looked like a square wave with the top slanting steeply from the front to back. I also noticed that the output of the converter never got above 4.4VDC. I eventually deduced that the mosfets in the level converter were simply too slow.

After some research, I discovered that some other people have had success using the SN74HCT245 as a one-way level converter that gives nice clean square waves at five volts for the output. I've ordered some today, should have them next week. I'll try to remember to update this post with the results.

Ray
 
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