Last Christmas I used a LPD8806 LED light strand for some festive decorations. The wife and kid thought they were pretty cool. So much so, that they decided to get me another strand for a present. Life being what it is, I never really found the time to play with the new strand. Fast forward to the present and I'm getting out the light project to get ready for this Christmas. I'm having some trouble getting things to work with the old strand. (Turns out the problem was me having the microcontroller ground and the strip ground not connected.) In the process of troubleshooting my setup, I switch out the LED strip completely and notice that the "newer" strand doesn't seem to work at all. I should add that until I started this debugging process (within the last week), this strand was still unopened in its ESD bag.
The setup I have is a RaspberryPi controlling the lights using the SPIbus and a home-made wire that connects to the strand via the JST connector. I'm using the RPi-LPD8806 python library. The current state is and things I've tried are:
- 1. One strand works fine, and when I disconnect it and connect the other strand, nothing happens.
2. Both are full 5m strands.
3. I verified that the input side of both strands corresponded to the JST connector I was using.
4. The non-functioning appears to me to get warmer than the working and lit strip after an equivalent amount of time.
This is a picture of the setup with the working strand. And a close-up of the working strand. And for completeness, a close-up of the not working strand. You can see that the spool shows a different item #.