this post was submitted on 18 Nov 2023
4 points (100.0% liked)

Ask Electronics

3316 readers
1 users here now

For questions about component-level electronic circuits, tools and equipment.

Rules

1: Be nice.

2: Be on-topic (eg: Electronic, not electrical).

3: No commercial stuff, buying, selling or valuations.

4: Be safe.

founded 1 year ago
MODERATORS
DavideAndrea@discuss.tchncs.de
linker3000@discuss.tchncs.de
4
Fixed address WS2811/WS2812b clones. (lemmy.world)
submitted 1 year ago by cynar@lemmy.world to c/askelectronics@discuss.tchncs.de
4 comments fedilink hide all child comments
 

My Google-fu has completely failed me. I've got an RGB addressable led curtain. It has 20 strings of 20 LEDs in a square arrangement. I initially assumed it had a wire feeding led data back up, to go to the next drop. On checking however, they are T jointed.

Apparently the address is hard coded into the RGB controller in the LED. I've found a few places where others have talked about them. I've also found that adafruit had some available,, unfortunately they lacked any info on how they are programmed, or where to source them from.

https://www.adafruit.com/product/4917

Anyone got any info on what the chip name of these is? Even better if you have any info on how they are programmed etc!

you are viewing a single comment's thread
view the rest of the comments
[–] mvirts@lemmy.world 2 points 1 year ago (1 children)

On the adafruit page it says:

These LEDs are not shift registers. In fact, if you look closely, there's no input and output pin, only one data line. That's because each LED in this strand is pre-addressed from 0 to 100. Whenever it receives the NeoPixel data, it picks out the n'th color data (matching to its pre-address) and displays that. You cannot change the pre-address, its fixed permanently - or at least, we have no idea how to re-address it.

[–] cynar@lemmy.world 1 points 1 year ago (1 children)

Yes, I read that bit. I'm trying to find out more.

They are obviously made in bulk, somewhere in china, since they are quite common, and cheap. Unfortunately, I've only found them in pre-built products, and none actually identify the chip model.

They obviously can be programmed (at least once) since you can buy arrays of at least 400. There is no way a factory is making 400 different chips, given the end price.

[–] mvirts@lemmy.world 1 points 1 year ago (1 children)

Are you looking for info on how to set the led color or something else?

[–] cynar@lemmy.world 2 points 1 year ago

I'm after a name or model for the chip/led itself. Potentially along with info on its extra functions.