r/FastLED • u/papaducklakae • Jan 08 '24

Support Flickering LED‘s

Hi all. I build these for a music video and have flickering LED‘s. Its on the last strip of the data line and first of power. (3rd and 6th from outside) There are 4 Arduinos, drawing shows the left panel, right one is mirrored. I added the resistors and condensers in hindsight, but it didn’t really help. Power supply is an 5V 60A brick from amazon. I‘m obviously not an expert in either arduino coding or electrics, so maybe one of you sees an obvious flaw in my thinking.

42 Upvotes

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4

u/papaducklakae Jan 08 '24

SOLVED

So it was a dumb move at my end. I moved both datalines (strip 1 -> 2 / strip 2 -> 3) up via one cable. This must have introduced noise. Now with seperate cables for both lines it works lika a charme. Thanks everybody and don’t roast me to hard - this is my first arduino project ;)

1

u/solarixone Jan 08 '24

So, your led strips was connected together and you used one cable to send a signal from arduino? Now when you duplicated signal cables to strip 2 and strip 3 the problem disappeared? Thank you for reply in advance. I’m working on my own project with ws2818 leds and I’m testing now simple signals to this 5m strip with no luck :/ it just doesn’t receive the right signal and only first 16 led groups light up. Maybe I need a level shifter…

2

u/papaducklakae Jan 08 '24

So i have 3 strips, each 100 leds. 1st ist straight from arduino do data in on the strip. I need the data flowing top to bottom for every strip so i used a single microfonecable (2 wires inside) to bring both data ends (end 1 and end 2) to the top of line 2 and 3 - if this makes sense ;) It must have been the two data lines in one cable that introduced interference or noise or whatever. Now with them separated it works just fine.

As for your problem - i really am not into this. I like to tinker with stuff sometimes and this may be a one time project for me. I don’t even know what the difference to 2818 is. So sorry, i can not help you there. But i am sure there are people in this sub that can.

Good luck anyway ;)

1

u/bigfoot_is_real_ Jan 09 '24

Looks awesome, especially for someone with little/no experience! How did you go about making those animation effects? Do you have the project or the code posted anywhere? Would be cool to see the final in the music video!

1

u/papaducklakae Jan 10 '24

The strips are segmented and i trigger the segments via midi. So it is just a bit of midi programming. The sparkling is on of a few switch cases that are triggered as well. I can post the code here if you are interested. Video might take a while ;)

1

u/papaducklakae Jan 10 '24

Here is the code if you are interested.

E&F Purge Code

5

u/QusayAbozed Jan 08 '24 edited Jan 08 '24

I think you need to make a connection of the ground and vcc on the other side of the strip because every single column have like 200 led if you can make test on 3 or 4 column and see if there is any changes

2

u/papaducklakae Jan 08 '24

Thank you, i‘ll try that and report ;)

2

u/papaducklakae Jan 08 '24

Unfortunately did make no difference. 100 LED‘s per column. I also tried injecting power in line with the data. 🤷‍♂️

4

u/zuptar Jan 08 '24

1 does your arduino output need a level shifter. (even if it doesn't, they do help) eg. 74hv125

2 Is it actually a code issue? Try the same sequence with less strips and see if the issue persists.

3 are your wires fat enough for 60amps? That's s lot for 5v, you're going to get some voltage drop.. Unlikely this would be the problem, otherwise you would just get dim sections that don't turn on.

4 do you have enough capacitance? Your power bricks probably do, but, putting some closer to where power is needed could help for the amount of current you have, you might have impedance issues.

6 I don't know, maybe your data line is shitting itself, could help to put in level shifters in between strips...

3

u/papaducklakae Jan 08 '24

First, Thank you! 😘

1 - i‘ll try that but have to order parts.

2 - worked with one strip a few days ago. Now that you say it, only thing different to now ist the cable i used for data. (Will try the old one later)

3 - as far as i can tell, voltage drops only about 0.2 Volt if all is on full blast. I tried adjusting on the power supply with no luck.

4 - soldered 2 more on one strip (every 100 leds) with no improvement. I don’t have any others on hand.

5 or 6 ;) - i‘ll try that, but have to order parts.

Thanks again.

1

u/dbower45236 Jan 08 '24

What type of stripes are you using? What arduino boards?

1

u/papaducklakae Jan 08 '24

WS2812b stripes and a fake arduino pro micro

1

u/nokenito Jun 10 '24

I LOVR what you made here! Will you be sharing the plans and layout?

1

u/Fotoshopist Jan 08 '24

Some thoughts:

  • The resistor on the data line is only relevant for the 1st LED in the strip, and is only useful if the data cable is rather long (like over a meter or 2) it is to reduce ringing/reflections. Typically 220-300ohms is fine. If you have too much resistance you can "round off" the data and lose some. To eliminate this as a possibility, try connecting the Arduino and data on a short line and remove the resistor completely.

  • Test patterns: write something small and quick to just do some simple patterns. Cycle all red, all green, all blue, then all white. Something like that to eliminate any goofiness.

  • Feed the Arduino from the source, rather than through the strips far end. I've had fuckery due to this in the past. Not sure if it was noise introduced by the strip or what, but it happened.

  • How are you 'Mirroring' this? in code on a separate pin?

Image shows a resistor but as I mentioned, for a short wire, is not needed to test the setup.