Strange problem, hoping some here have an answer.

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(Stuart Sands) #1

Strange problem, hoping some here have an answer. I’m using an Arduino-compatible controller (Sparkfun ESP8266 Thing Dev)and FastLED to drive a strip of APA102c leds. When I connect the controller to the strip, it works great. If I connect through a 4 foot extension cable (so approx. 4 ft between controller and strip), I get mostly bright blue, with just a hint of the pattern I should have. Switch out the extension, and it looks like it should.
Any thought as to what I can do to so that the extension doesn’t do this? I’ve tried other extension cable with the same results.

(Leon Yuhanov) #2

Are you using a Voltage Level Shifter for the DATA and CLK pins? If not, you should be. Alternatively, connect 1 pixel super close to the dev board, and use it as your booster

(Marc Miller) #3

@Stuart_Sands here’s one of the recommended level shifters and how to wire it.
Imgur

(Marc Miller) #4

Another thing to try could be running your signal lines like this in a twisted pair line. This helps avoid signal interference.

(Stuart Sands) #5

@Leon_Yuhanov I have only level shifted the data, not the clock. I hadn’t thought of that. I suppose I’d better do that, yes?

(Stuart Sands) #6

@marmil I grabbed some CAT5e cable today and was gonna try that for the twisted pair. I’ve used the level shifter, but never did it for the clock - wondering if that will help…

(Leon Yuhanov) #7

@Stuart_Sands Yes both DATA and CLOCK and you should be golden:)

(Stuart Sands) #8

@Leon_Yuhanov @marmil . I level shifted data and clock (had only shifted data previously). No diff. I lowered the data rate down to 1 KHz. No Diff. I subbed out the crappy 4-conductor cable with cat5e twisted pairs and it works. Damn, I must have some really, really lousy cable. Now, I’ve got a ton of re-wiring to do on 3 costumes (one with 8 parallel strips). I so very much appreciate everyone’s help on this. I would not have come up with using twisted pair on my own. Thank you all.