How does a WS2811 led strip default pattern colors work?

Other Hardware LEDs and Multiplexing
1

I have a WS2811 led strip and when I turn on the 5V power source connected to the strip, it starts to do some color patterns, it is some kind of demo/presentation that most of these strips have.

Where is this coming from? How does it work?

Why am I asking this? Because I cut this strip in two parts and I was able to control the leds from the second part (farther away from the beginning), but I can't control the first part, it is always running the "demo/presentation patterns".

Any ideas? Should I just jump and cut the first leds out?

2

We can't help without more information, like a link to the strip you have, or at least some pictures.

But ordinary ws2811 strips don't have any default colours or patterns. Your strip must have a controller chip somewhere.

3

It does seem to have an additional component on the first section, that doesn't appear anywhere else on the strip. Is that it? Can it be removed?

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4

And we have no idea. :roll_eyes:

OK, I suppose we do. :grinning:

This strip is a novelty, an outlier; that does indeed appear to be a microcontroller generating the patterns. It has a 5 V regulator next to it.

If you really don't like it, just cut that first module off at the copper pads on the right of your photo.

5

Interesting, never seen that before. I guess the extra components we can see are a microcontroller of some kind and a voltage regulator to supply it with 5V.

I guess you could cut off that first section and the rest of the strip would work as an ordinary ws8211 strip.

The strange thing is that there is a "DI" (data-in) connection on the strip. Why would that be there if the built-in controller cannot be overridden?

6

PaulRB:
The strange thing is that there is a "DI" (data-in) connection on the strip. Why would that be there if the built-in controller cannot be overridden?

Ah, you did notice that. :grinning:

I thought it might be some sort of override or simply a pattern select input such as the button on Christmas light controllers - which would probably ignore rapid data streams as it would have a de-bounce routine.

7

Paul__B:
I thought it might be some sort of override or simply a pattern select input such as the button on Christmas light controllers - which would probably ignore rapid data streams as it would have a de-bounce routine.

@thiagolr what is the centre ("DI") cable connected to?

8

It is connected to my Arduino Uno, but it doesn't work, it doesn't control anything...

The other led strip segment which was cut from this one works ok, with the same setup (DI connected to Arduino)...

9

I meant originally what was it connected to? Or was it like that when you purchased it? Can you post a link to where you purchased it?

10

There was a "dc jack" connector using the +12V and GND, no connection on DI.

I purchased it here:

There is a video there showing the color patterns and also the connection.

11

Hmph! Very informative.

12

I see a bulge in the cable. What is that?

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Can you give a good picture of that?

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13

I don't have that, it is probably from his power source.

This is was I cut from my strip:

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14

Oh. It will remain a mystery.

15

PaulRB:
https://produto.mercadolivre.com.br/MLB-717358222-fita-led-rgb-5050-5mt-w2811-enderecavel-150-3m-led-ip65-_JM
Hmph! Very informative.

Should of course, have been included in the very original posting. :roll_eyes:

16

I cut that first section off and everything worked as expected, thanks for your help!