Converting cheap multicolor LED tape to addressable LEDs?

[Galane]

I've been seeing some rather inexpensive multicolor LED tapes with a control box attached which can have color patterns move along the tape. To me that implies the controller is sending signals to a number of the LEDs then repeating that pattern down the string.

I'm wondering if I could take one of those cheaper than a tape of Neopixels units and replace its control box with an Arduino or other programmable control system and individually address the multicolor LEDs?

I have a project that needs 80 multicolor LEDs in a 16x5 grid, with programmable colors, and in a separate unit 80 switches, with each switch controlling the on/off state of one LED. The current setup is a vintage thing from the 1960's with a very 'brute force' setup that simply has a large number of wires inside a flexible tube.

Cutting that down to an Ethernet or USB cable would be very nice, as would being able to use different colors for the lights instead of just the white incandescent bulbs being on or off, and frequently burning out then being expensive to replace because they run on 28V DC.

 

[Dave_H]

removed (duplicate)

 

[Dave_H]

Many low-end RGB strips have all R, G, and B wired in parallel so the each colour can be controlled independently, but all LEDs in the string are the same, so no moving patterns possible. There is a variant with separate R,G, and B LEDs spaced out, also with parallel control, so has some limited moving pattern capability.

I think what you refer to uses serially-controlled LEDs which are daisy-chained. Have a look at World-Semi WS2811 driver chip; or WS2812 integrated with RGB LED. This gives independent control of each LED in the string, lots of pattern capability. I have no experience with this, but someone on here should have, or know someone who has reverse-engineered the serial data protocol to work on R-Pi, Arduino etc.

Dave

 

[LEDphile]

Probably easier to just buy the LEDs used in the strips instead of trying to cut down a strip. They are easy enough to find online - Adafruit is one such vendor (they sell them as "Neopixels") and as a hobbyist-oriented vendor, also has Arduino examples.

 

[PhotonWrangler]

+1 for Adafruit. They carry tons of addressable RGB and RGBW strips along with tutorials on how to drive them from an Arduino, RaspberryPi or a FadeCandy module. Check out their Dotstar line also, which works better for faster patterns and video, Dotstar is all 2-wire SPI.

 

[Dave_H]

Not exactly what OP is looking for but related; I am pleased to find that for two low-cost RGB LED 10" "selfie" ring lights I've picked up recently, both use addressable LEDs. They are under brands "Premier" and "SOAR" around here OTC, both around $10. No WiFi, BT or IR remotes on these, strictly in-line selection of mode and brightness (fine for me at this price). Power is from USB.

Packaging showed multiple colours on at the same time which means addressable LEDs, compared to all LEDs on same colour/brightness which is a limit of cheap strips with all LEDs wired/controlled in parallel.

Inside one ring light was found 48 4-pin 5050 RGB LEDs which I am not able to identify yet. There are various pinouts and function (including data interface) among a few devices I found data for.

For now I'm happy with available colour patterns, no need to hack it i.e. connect to a different controller, but looks do-able, and the price was right.

Dave

 

[Galane]

Temu has tons of RGBW and RGB LED tapes but so far I've yet to see any that are truly multicolor. They show pictures of them lit up with several colors at once but that ain't what you get.

 

[Dave_H]

Temu has tons of RGBW and RGB LED tapes but so far I've yet to see any that are truly multicolor. They show pictures of them lit up with several colors at once but that ain't what you get.

Yes, LED tape packaging can be misleading. They sometimes show multiple strips, each with different colour.

There is a variation with separate R,G, and B LEDs spaced out, which allows some level of motion effects but not colour mixing. (e.g. "XTREME RGB Flow" product).

Here is shot of the ring in RGB pattern mode snapped with 1Mp camera which does
only a fair job of rendering the colours. For some reason, my 6Mp and phone cameras
do not capture the colours well, must be some mode/setting.


Dave

 

[alpg88]

I have a strip like this, unlike regular 3 color rgb strips, which have separately addressable colors, those have an individual ic controller for every 3 leds, so the controller box is really talking to controllers of each individual cluster, which are turning leds on off in certain sequence, in theory you can program that main controller to do anything really, if you know how.

 

[Dave_H]

I just recently had a close look at a short piece of strip, what you describe. It uses WS2811 control chip for every three LEDs, run from 12v. For efficiency, three LEDs of each colour are wired in series. They can be controlled in groups of three. The LEDs in the ring have RBG LEDs combined with driver, so every RGB can be controlled separately.

The WS2811 can control only one RGB LED, but that would triple the number required.

Dave

 

[Galane]

I found these, individually addressable and conveniently spaced 3" apart on wires. https://www.temu.com/set-ws2811-pix...-12mm-dc-5v-dc5v-50pcs-g-601099514334029.html

But no mention of what's needed to control them. One person posted a review saying the work with WLED and a Node MCU controller.

I'm wanting to turn them on and off individually and set their colors. Still looking for a method to wire 80+ switches into a matrix and poll them to upgrade an old BINGO flashboard. It has to be able to map the switches 1 to 1 to the LEDs and be able to read all the switches simultaneously closed. That's a situation *possible* but in practice rarely, if ever, achieved in a blackout game. But I bet if it was capable of handling any less than all switches closed, it wouldn't take long for random chance to have a game go to all balls drawn.

 

[Dave_H]

WS2811 driver is from World Semi (www.world-semi.com). Datasheet is available. They also have WS2812 which is driver integrated with RGB LED. Any controller needs to be compatible with this. I have found different driver/LED devices from World-Semi and Bright LED Electronics Corp. World Semi shows strips and controllers on their site.

For switch matrix I imagine you would use push-button or toggle (spring-return) to cycle through multiple colours and on/off? Or would flipping regular toggle switches back and forth do it? How that would feed into the LED controller is a good question. The matrix needs to accept multiple closures while avoiding "phantom" switch detection; not complex but has been awhile and I forget the details.

Unless you find a controller specifically designed to interface to a switch matrix, this is looking more like a "custom" job. Not only the hardware, but mapping the switch activity to desired colours/states/sequence is a further complication. Sounds like a Raspberry Pi or Arduino with the right SW and HW interface would work, sorry I can't offer any specifics.


Dave

 

[Dave_H]

I am wondering if you could take advantage of USB keyboard mechanism for encoding switches. You may be limited to momentary switches but should be able to deal with multiple simultaneous press up to some limit. Of course now it's a matter of software to interpret/map and format this all into light settings; and getting it into the controller whose SW you'd need access to. Raspberry Pi has USB and a good possibility.

Dave

 

[HarryN]

Yes, LED tape packaging can be misleading. They sometimes show multiple strips, each with different colour.

There is a variation with separate R,G, and B LEDs spaced out, which allows some level of motion effects but not colour mixing. (e.g. "XTREME RGB Flow" product).

Here is shot of the ring in RGB pattern mode snapped with 1Mp camera which does
only a fair job of rendering the colours. For some reason, my 6Mp and phone cameras
do not capture the colours well, must be some mode/setting.


Dave

View attachment 44903

Your experience can spawn a very in depth / complex discussion that I won't go into here, but you are exactly right.

The inability to take some pictures with cell phone and a number of digital cameras (that were easy to take with film ) led me on a long and expensive journey. My wife can now take photos of waves breaking over rocks on the sea shore, and I can take photos of snow on a hill but it didn't come cheap.

The easiest explanation is that your camera sensor is based on 3 color science and that just is not enough to really capture what our eyes (or film ) can see.

 

[Galane]

I am wondering if you could take advantage of USB keyboard mechanism for encoding switches. You may be limited to momentary switches but should be able to deal with multiple simultaneous press up to some limit. Of course now it's a matter of software to interpret/map and format this all into light settings; and getting it into the controller whose SW you'd need access to. Raspberry Pi has USB and a good possibility.

Dave

I've not found a keyboard controller that can read 75+ keys simultaneously. What the system would need to do is poll the key matrix every n time and update the output, leaving the corresponding LEDs lit until a clear switch is momentarily closed to turn the LEDs all off.

 

[LEDphile]

I've not found a keyboard controller that can read 75+ keys simultaneously. What the system would need to do is poll the key matrix every n time and update the output, leaving the corresponding LEDs lit until a clear switch is momentarily closed to turn the LEDs all off.

If you want a single "clear" switch, that leaves you using momentary switches to set state. And for that, you don't need to read more than a few (perhaps even as low as 1) switches simultaneously. But for that approach, you don't get any state indication from the switches unless you add individually addressable LEDs for the switches as well. And yeah, a USB keyboard with custom keycaps is probably going to be your easiest option. If you do want to fabricate something, a simple matrix of rows and columns with switches connecting a row with a column should work for this application.

 

[Galane]

If you want a single "clear" switch, that leaves you using momentary switches to set state. And for that, you don't need to read more than a few (perhaps even as low as 1) switches simultaneously. But for that approach, you don't get any state indication from the switches unless you add individually addressable LEDs for the switches as well. And yeah, a USB keyboard with custom keycaps is probably going to be your easiest option. If you do want to fabricate something, a simple matrix of rows and columns with switches connecting a row with a column should work for this application.

The bingo balls fit into holes, each with a momentary switch. When a game is over a slide is moved down to drop all the balls back to the blower cabinet. Releasing all the switches should clear the board but having an extra switch would be a useful signal to set the system for the next game. Patterns, colors etc could be pre set so the bingo caller wouldn't have to do them between games.

The switches could be constantly scanned for state changes, and the state stored as a 2D array. https://e2e.ti.com/blogs_/b/analogw...umber-of-i-o-pins-with-a-switch-matrix-module

75 switches would need 20 I/O pins. More than 20 to add a few more.