I get 0V on the data line right now and the controller says that it’s still sending the RGBW test signal. That could be my cheap multimeter not being able to pick up the signal due to change rate.
You need to address why the BBB won't power off your Cape as your first problem.Update from my first round of tests this morning. I swapped in my second power supply and still having issues.
All outputs are set to 20%
1. Tested on solid red with a single strand of 50 pixels using just the 18" pigtails. This works fine on the 4 outputs I have wired up.
2. Tested on solid red with a single strand of 50 pixels using the 18" and a 5' extension. This has flickering on all 4 outputs.
3. Tested on solid red with a single strand of 50 pixels using the 18" and a 10' extension. This has flickering and color issues.
4. Tested on solid white with a single strand of 50 pixels using just the 18" pigtails. This has flickering.
My green connections seem solid - I can pull them off the board by the cabling. I did cut output 2 back to remove the tinning, but can't see that it made a difference compared to the others.
I'm still not seeing any voltage on the data line. This is supposed to be compared to ground at the end of the string, right? I get ~4.7V at the end of the string comparing V+ to ground so my multimeter is working.
Ground isn't looping back to anything. It comes in from the PSU and lands on the board.
I am powering the BBB from the USB input because it won't power up from the board. Could that be causing an issue since they aren't sharing a common ground through the PSU?
Yes that is not right as it should be 5v.
I show continuity to the 5/12 jumper, but oddness to J2 and the 5V header. My meter reads 0 for continuity and those 2 register as ~.7Yes that is not right as it should be 5v.
There is minimal circuitry between your power input on the right and the rest of the circuit.
Unless you have blown the fuse or diode I am still leaning towards the 5v/12v jumper being the issue
With all the power off and your meter set to continuity mode (should beep when you touch the leads together) test from + on the right power input to the 5v/12v jumper and from + to J2 and + to the 5v on the header near the LCD.