Okay, I tried connecting the LED strip to all 3 pins on the board and used only one power supply to power the lumazoid board. http://i.imgur.com/khw6o3w.jpg
Now sometimes some LEDs light up when I hold a button while powering on, but not everytime and it seems random and they “freeze” – meaning only the LEDs which lighted up on power on are on but nothing else happens.
btw, I’ve ordered two lumazoids and I have the same problems with both, so I think it’s either my LED strip or maybe my power supplies which cause the problem… I ordered some new ones and will see if that fixes the problem.
Yes, the blue LED does blink a few times when I power on the unit.
The wires from the Lumazoid to the strip are very short (approx. 10cm).
On DOUT I measure 2.10V.
Just to make sure (as I’m not an expert in electronics): connecting all GNDs together would be the right way? As said, it works for the Arduino Nano but I’m not really sure if this is the right approach for the Lumazoid too.