Hello folks!
I was wondering two things about metering the data line on a ws2812B strip.
Firstly, could one check for resistance value by checking the first and last pads on the strip?
Secondly, could you meter the current at the end of the powered (and receiving data) strip to verify that data is reaching the end?
I’m trying to diagnose a problem in a line and I want to know if it is data related. The code is effective on other cut strips off the same roll, so the voyage of progressive diagnosis continues.
Thanks for reading!
Firstly, could one check for resistance value by checking the first and last pads on the strip?
Probably not, every LED has a IC in it and the data gets processed and repeated by the IC, it’s not a continuous path from one end of the strip to the other since every LED interrupts the path.
Secondly, could you meter the current at the end of the powered (and receiving data) strip to verify that data is reaching the end?
You’re dealing with digital logic, current is likely in the microamp range and it’s not a continuous signal. You might see some current flow, but the current would vary depending on what data happens to be on the bus at the time. The best way to see if data is present would be to connect an oscilloscope to the data line at the point you’re testing and see if you are getting some sort of square wave. If you are, data is flowing. In a pinch you could use a logic analyzer in place of a scope, but the scope would be easiest to quickly see if something is there.