The excellent tutorial for these pixel strands (http://www.ladyada.net/products/rgbledpixel/
) recommends:As shown below, connect ground to both your supply and logic microcontroller. Then connect the 5V pin to the power supply. A large capacitor (1000uF or so) is a nice addition to keep ripple down.
Forgive my ignorance, but I'm not sure where to put said capacitor. Is it series between the 5V power supply output and the the strand's power input wire (the red wire)?
P.S.: I think there are two small bugs in the library for the pixels that's posted here: https://github.com/adafruit/LPD6803-RGB-Pixels
. Specifically, both the 4-argument version of) setPixelColor in LPD6803.cpp, and the Color function in strandtest.pde, seem to place the r, g, and b arguments in the wrong order. i.e. r should be the 5 highest-order bits, then g, then b. (1) How best to alert the authorities? Does this suffice? (2) I may of course be wrong, but when I use the code as is I don't get the colors I expect, and when I modify it I do. So if I'm wrong can you explain what's going on?