What’s the best way to tell if an LED (WS2813 or 2812) is passing a data signal? When I measure the voltage, I only seem to get a reading when measuring AC, and with just the red lead attached. And even then, it seems to fluctuate from 2V to as high as 20V. With black lead attached to GND, it goes to 0.
Is it more or less a binary thing, i.e. if you get a voltage, then it’s being passed?
Trying to troubleshoot a ~35’+ jumper that has 3 repeater LEDs in it. At point point it worked, but now only the 2nd repeated LED lights, it’s dark from there on. And it’s a PITA to work with, given its location.
The best way is with an oscilloscope. Configure for rising edge trigger and set trigger holdoff to slightly longer than the number of LEDs * 30us. Proper holdoff setting will allow you to horizontally scroll through the data without false triggering frustration.
Using only a multimeter is difficult at best. Both 0s and 1s are fast pulses, differing in width but both are at 800 kHz, which is higher than the AC bandwidth of virtually all handheld meters.