Controlling WS2812 device (RGB LED strip)



  • @Luciano-S. It's a bot, no point in talking to it. Just report its posts and move on.



  • @Luciano-S. Your comment is OK, but please remove your unneeded quote (it's still spam).



  • @WereCatf said in Controlling WS2812 device (RGB LED strip):

    @Luciano-S. It's a bot, no point in talking to it. Just report its posts and move on.

    It is just a shame that there are no admins around to keep order here ... bot or not, make order is up to them.



  • @Luciano-S. I agree - haven't seen the admins around here for a long time - and there are a few issues that need addressing. I know they will have been busy with getting the Omega2 out, but now that it is being delivered is just the time we need their presence



  • @Kit-Bishop i believed it was not a startup campaign anymore ... but it looks like that they do similar mistakes again.
    Letting wait a active community makes ppl move on ... good that there are other IOT projects with a good working infrastructure ;-)

    Tony Stark is definitely missing in this forum :smile:


  • administrators

    All of our Tony Starks have been heads down on getting to Omega into the hands of all of the backers, so we've been absent from the community for a little while.

    @Kit-Bishop @Luciano-S I agree, we need to be more present on the Community and it's definitely our New Year's resolution :)
    Expect to see a LOT more of us around here from now on.

    (I've deleted the spam btw)



  • i think you can use SK9822 LED Strip , just use the dotstar APA102 liBrary , by the way , WS2813 is also a choise , as it is faster and one led broken will not affect another



  • Timing of the WS2812B and SK6812 LEDs ( datasheet http://www.ledlightinghut.com/files/SK6812 LED Datasheet.pdf ) is not as critical as the datasheet alludes to. The only thing that matters is the high time for setting either a 0 or 1 bit.



  • @Matthew-Dewey yes, the signal high time is what needs to be precise to ~100nS. However, while the low time can be much longer than stated in the datasheet, it still must be below about ~10uS (for WS2812 and P9823; WS2813 allows up to 100uS). Otherwise, the chain will reset too early.

    Now the problem is that there are interrupts taking more than those 10uS. So to produce flicker-free updates for a WS2812 chain, interrupts need to be disabled during the entire chain update, which means several milliseconds. This works (ws2812_draiveris does this), but it's ugly and completely messes up all other timing that might go on in parallel.

    On the Omega2, there's a PWM unit that can help a bit. It's not perfect because it lacks DMA support, but it can generate chunks of ~20 bits of WS28xx payload at a time, entirely in hardware, and can be re-filled via interrupt. See here for an attempt to do it this way ;-)



  • we supply the ws2812b led, Learn mpre please contact jessie@witop-tech.com. we will give you more news about Led.


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