Forum Rule: Always post complete source code & details to reproduce any issue!
Results 1 to 6 of 6

Thread: OctoWS2811 to drive pl9823

  1. #1

    OctoWS2811 to drive pl9823

    Hi there

    Try to use in my project PL9823 leds PL9823.pdf

    after about 30 leds - controll signal distorted and leds work not correct.
    But test with 100 leds in single color mode(255 level of each color) work fine.
    if just some leds work (not all 100 pcs) - leds work not correct

    main trouble in timings difference between WS2811 and PL9823

    how i can resolve this? or how i can help?

  2. #2
    Senior Member PaulStoffregen's Avatar
    Join Date
    Nov 2012
    Posts
    19,532
    These types of problems are almost always due to inadequate power line wiring. As you increase the number of LEDs, the increasing current in the ground wires causes more voltage change in ground, corrupting the signal.

    OctoWS2811 has been used for very large LED projects. I personally worked on this one, with 4320 LEDs.

    http://community.arm.com/groups/embe...ker-faire-2014

    Notice in that project the large number of #22 size power wires, feeding each row of 90 LEDs from both sides.

    OctoWS2811 can easily drive 100 LEDs. OctoWS2811 was released in March 2013. Since then, thousands of people have used it to build large LED projects. These reliability problems have been seen many times, and they almost always turn out to be wiring problems.

    If you're getting problems with incorrect results, OctoWS2811 should be the last place to suspect trouble. It is very mature, very widely used software that has been very well tested.

  3. #3
    Thanks for answer, maybe i am not correct explain
    with WS2811 all fine
    when i use pl9823 - trouble
    i check signal timings - almost same - but not exactly

    i try to use more better power system and share results

  4. #4
    Senior Member PaulStoffregen's Avatar
    Join Date
    Nov 2012
    Posts
    19,532
    Normally I do not recommend changing the waveform timing.

    However, if you have LEDs with different requirements, you can edit these 2 numbers to adjust the high time for 0 and 1.

    https://github.com/PaulStoffregen/Oc...WS2811.cpp#L64

  5. #5
    Senior Member PaulStoffregen's Avatar
    Join Date
    Nov 2012
    Posts
    19,532
    You can also change the overall frequency here:

    https://github.com/PaulStoffregen/Oc...WS2811.cpp#L97

    That datasheet says T0H + T0L = 1.71 us, which is 584795 Hz. Just replace 800000 with 584795 to slow the waveform.

    The 2 timing parameters are very close. You might try 53 and 203, maybe?

  6. #6
    Junior Member
    Join Date
    Dec 2018
    Posts
    1
    Quote Originally Posted by PaulStoffregen View Post
    You can also change the overall frequency here:

    https://github.com/PaulStoffregen/Oc...WS2811.cpp#L97

    That datasheet says T0H + T0L = 1.71 us, which is 584795 Hz. Just replace 800000 with 584795 to slow the waveform.

    The 2 timing parameters are very close. You might try 53 and 203, maybe?
    Thank you for these details!

    I'm running a fadecandy currently and had the same issues. I tried just changing the timing parameters to 53 and 203 as suggested, but this made things worse (nonstop flicker on every LED). I've now changed just the overall waveform value from 800000 to 584795 and it is much better! I'm wondering now if I should now try a combination of both changes? I'm quite new to this, but hope this feedback may help someone else.

    Thanks,
    Matt

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •