Author Topic: P10 panel flickering outline  (Read 3312 times)

Offline JonB256

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Re: P10 panel flickering outline
« Reply #30 on: October 09, 2017, 10:39:50 AM »
Making that last set of changes (from 130 to 300 and 1 to 2 ) removed almost all the flicker and ghosting.

Reducing brightness in LED Panels to 70% got rid of the rest of it. Thanks.

Offline Bshaver

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Re: P10 panel flickering outline
« Reply #31 on: November 01, 2017, 01:34:37 PM »
I was able to make some progress with this issue. Since FPP is using an older version of the RGB Matrix library, the settings shown in the documentation that I mentioned earlier are not available.

I was able to find a constant in the code that controls the PWM Nanoseconds for LSB. I manually changed it and rebuilt FPP using the following.

Code: [Select]
cd /opt/fpp/external/rpi-rgb-led-matrix/lib
sudo nano framebuffer.cc

modify the following line "static const long kBaseTimeNanos = 130;" and change 130 to 300
Save the file and exit

sudo make
cd /opt/fpp/src
sudo rm fppd
sudo make

I then restarted FPP and ran some tests.

The ghosting is now gone for the most part. It still seems to show a little when the text is first displayed but goes away completely after a second. So, I don't know if there is something else in the code that needs changed.

Would it be possible to update the library to the latest version and add this as a setting on the matrix page? I would be willing to do this myself even it was only on my local copy, but I am not that familiar with Linux or the FPP code. So, I would probably need a lot of help.


Just a FYI: I finally..finally got around to doing this, and I can say that this change has made a big improvement to the aliasing / ghosting on my P10 panels.


I was seeing the aliasing on my panels through my color light board, and this resolved that as well.


Thanks for the help on this one!

Denver Colorado
45,000 blinky blinks mix of pixels and 130 AC Channels (powered by Minleon & Lynx) ALL Powered by FPP and Falcon!

Offline JonB256

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Re: P10 panel flickering outline
« Reply #32 on: November 06, 2017, 09:37:00 AM »
I had done the above change with good results (flickering at "end of string")

but did a re-install after a Texas sunshine temperature related crash. Started flickering again because it went back to "130" instead of "300"

If you are using a RasPi Matrix hat, I highly recommend this change. If you follow those instructions to the letter, it is worth it.
I only restarted FPPD when done and it worked fine. Didn't need to reboot.

Offline brichi

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Re: P10 panel flickering outline
« Reply #33 on: January 07, 2018, 07:28:05 PM »
I have been trying to use the sudo nano frame buffer.cc line above but I get the following when I hit enter and I cannot edit anything or move forward




/
  GNU nano 2.7.4                                               File: framebuffer.cc                                               Modified 
                                                                                                                                           
// -*- mode: c++; c-basic-offset: 2; indent-tabs-mode: nil; -*-
// Copyright (C) 2013 Henner Zeller <h.zeller@acm.org>
//
// This program is free software; you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation version 2.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://gnu.org/licenses/gpl-2.0.txt>
                                                                                                                                           
// The framebuffer is the workhorse: it represents the frame in some internal
// format that is friendly to be dumped to the matrix quickly. Provides methods
// to manipulate the content.
                                                                                                                                           
#include "framebuffer-internal.h"
                                                                                                                                           
#include <assert.h>
#include <ctype.h>
#include <math.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
                                                                                                                                           
#include "gpio.h"
                                                                                                                                           
namespace rgb_matrix {
namespace internal {
enum {
  kBitPlanes = 11  // maximum usable bitplanes.
};                                                                                                                                         
                                                                                                                                           
                                                                                                                                           
^G Get Help    ^O Write Out   ^W Where Is    ^K Cut Text    ^J Justify     ^C Cur Pos     ^Y Prev Page   M-\ First Line M-W WhereIs Next
^X Exit        ^R Read File   ^\ Replace     ^U Uncut Text  ^T To Spell    ^_ Go To Line  ^V Next Page   M-/ Last Line  M-] To Bracket

/


Offline brichi

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Re: P10 panel flickering outline
« Reply #34 on: January 07, 2018, 07:42:16 PM »
not all pasted above, sorry but I don't see the line ""static const long kBaseTimeNanos = 130""



I searched every line, maybe the latest beta is different from 12/8/17? Is that just a Pi setting, Im using a BBB and have bad ghosting also

Offline rmp2917

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Re: P10 panel flickering outline
« Reply #35 on: January 08, 2018, 05:08:40 PM »
Use the arrow keys to scroll down to line 38. It should be 3 lines below the "kBitPlanes = 11".

This is only used on the Raspberry Pi. It will not effect the BBB.

Offline brichi

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Re: P10 panel flickering outline
« Reply #36 on: January 08, 2018, 05:17:09 PM »
Thats what I figured once I looked more into the code, I have the BBB so im still stuck with a ghosting pixel issue

Offline JonB256

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Re: P10 panel flickering outline
« Reply #37 on: January 08, 2018, 06:16:33 PM »
Thats what I figured once I looked more into the code, I have the BBB so im still stuck with a ghosting pixel issue

What BBB code are you using?  The Dan Kulp series (I'm using 3 of them) does not ghost.

Version: v1.9-bbb-138-g53088307 (bbb-stretch-v1.x branch)

http://www.dankulp.com/bbb/    (9.2 beta, latest version)

Offline brichi

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Re: P10 panel flickering outline
« Reply #38 on: January 08, 2018, 06:20:29 PM »
running the latest beta also, cant get this to work without the green following white - check it out here, I sound like crap cause im a little sick and the kids were going to bed so trying to stay quiet -  https://youtu.be/BnznhaxunZY


I have 2 BBB, one is running latest beta and one running non beta, I swap the Octoscrolla between the 2 and get the same results, I wonder if the Octo is bad?


dkulp has been in a thread I created helping out so hopefully its something he can fix in code

Offline JonB256

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Re: P10 panel flickering outline
« Reply #39 on: January 08, 2018, 06:23:52 PM »
If it is the Octo (and its begingging to look like that) it sounds like a bad decoupling capacitor to me. They are those tiny little yellow dudes near every IC chip on every board.

In your video, the green seemed to be above and below the white, but your layout seemed to be horizontal, so that may not be the cap.

Online dkulp

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Re: P10 panel flickering outline
« Reply #40 on: January 08, 2018, 06:28:29 PM »
If it is the Octo (and its begingging to look like that) it sounds like a bad decoupling capacitor to me. They are those tiny little yellow dudes near every IC chip on every board.

In your video, the green seemed to be above and below the white, but your layout seemed to be horizontal, so that may not be the cap.


The octo's don't have them.  The Octo's are really simple, there is just one chip on it and that's it.  So it's either the chip or a solder joint.  Usually if it's one of those, then you get something much more noticeable, like an entire color not working or an entire line not working or similar. 


That said, it kind of does seem to be power related somehow.   
Dan Kulp

Offline brichi

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Re: P10 panel flickering outline
« Reply #41 on: January 08, 2018, 06:51:19 PM »
so on a power end just so you know I am running a 5v/300watt and the BBB I tried running off that power supply and now I have it running off its own 5volt p/s just to eliminate that being the cause.


Offline Wichita

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Re: P10 panel flickering outline
« Reply #42 on: January 08, 2018, 07:56:37 PM »
I didn't plan ahead last year and bought my panels from 2 different vendors. 10 from 1 and 2 from another.  The fix for the pi helped a bunch but the 2 odd panels have issues.  The one thing I noticed is that the input and output are different and a few components are different. The board numbers are identical.  My matrix is still mounted above the garage right now but I think the panels with issues had the connectors on the outside set of solder pads and the good ones it was on the inside set. Could be the other way around but I can't remember.  I don't know if that means anything but it did follow that the panels with issues.

 

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