problems with panels bought in 2018 december

[fotosettore]

hi it seems something wrong in "new" panels 64x32 i bought first series of panels from a seller and no one works fine : random pixel on - no images - no text. pattern test and pixeltime both not working. i made about 10 building changing cables, panels, d1.mini and nodemcu. i changed all possibily software setup (zigzag, line, 1/16 etc etc) . no luck i think that new panel series, after 2018 october, changed in something, so them do not work with the available (oct 2018) pxmatrix library. i sent a my panels to a user that has a panel that works fine and confirm to me than they do no work. i saw other users complain about the same problem. today were delivered panels form other seller : same problem. any help ?

[2dom]

Have you ensured that there is a proper ground connection between ESP and panel? It may also be a timing issue..

[fotosettore]

yes, i had. anyhow the ground between power supply of panel and all ground pins of all connector are electrically connected together. so I do not think that's the problem. however i tried to connect ground of power supply to ground of nodemcu. same problem. the same sketch works fine on 64x64 panels. there are same wiring connection. please note i'm not only maker that complain about this problem : all last messages of last makers. the makers before october does not have this trouble. really very strange.

p.s. i removed some flickering problems using a prototype pcboard made with my cnc. this means that wiring connection must be as short as possible.

[2dom]

you could try reducing the SPI speed in the library...

[fotosettore]

SPI.setFrequency(20000000); this one ?

[2dom]

yes ... that's the one. The 20 MHz might be too much...

[fotosettore]

I will try and i will let you know. now I do not have the 32 panel at hand. many thanks for your support.

[fotosettore]

tried SPI.setFrequency(20000000) SPI.setFrequency(2000000) SPI.setFrequency(10000000) SPI.setFrequency(1000000) SPI.setFrequency(100000) SPI.setFrequency(40000000) SPI.setFrequency(4000000)

unlucky tests. in SPI.setFrequency(1000000) brightness is low tried more than one 64x32

tried on 64x64 ... all works fine

[houk001]

I have the same problem with panels 64x32 ordered 11 dec from sryled display https://www.aliexpress.com/item/P3-RGB-pixel-panel-HD-display-64x32-dot-matrix-p3-smd-rgb-led-module/32728985432.html 2 panels 3 nodemcu, 2 power supplies all the same, even pattern test not work as expected.

[fotosettore]

this is a half confirm that something changed in new panels :-(

[2dom]

Ok ... could you upload a picture how it looks like?

[fotosettore]

this is my "effect" but is random, because sometimes only some lines of led are present.

[2dom]

what is it supposed to show?

[fotosettore]

sorry ... pixeltime.ino

[2dom]

which part? The weather icons and the color bars?

[houk001]

This is my random effect from pattern test Sometimes the upper line is white sometimes yellow but newer is going to the end of panel. Always some parts are black

From: Dominic Buchstaller [mailto:notifications@github.com] Sent: Saturday, December 29, 2018 10:18 PM To: 2dom/PxMatrix PxMatrix@noreply.github.com Cc: houk001 houk@hawke.pl; Comment comment@noreply.github.com Subject: Re: [2dom/PxMatrix] problems with panels bought in 2018 december (#53)

Ok ... could you upload a picture how it looks like?

— You are receiving this because you commented. Reply to this email directly, view it on GitHub https://github.com/2dom/PxMatrix/issues/53#issuecomment-450520723 , or mute the thread https://github.com/notifications/unsubscribe-auth/ARjJlqS3bJJJopj8DYeZMicoZDOQ1r8_ks5u99v9gaJpZM4ZgXEY . https://github.com/notifications/beacon/ARjJlvnecCyGNjF6rn9J3NPvATAp7M8Fks5u99v9gaJpZM4ZgXEY.gif

[fotosettore]

i take the sketch pixeltime as is, i changed only PxMATRIX display(64,32,P_LAT, P_OE,P_A,P_B,P_C,P_D,P_E); and display.begin(16);

[2dom]

Could you generate a video with the pattern test?

[fotosettore]

this is the pattern_test.ino with same needed changes also here all is random ... sometimes different colors and pixel light

[2dom]

I need a video with one full cycle - red,yellow, white

[fotosettore]

i make video but NO CIRCLE ... all pixels are stopped

[fotosettore]

in ten minutes i make a video with 64x64 e 64x32.

[houk001]

For me pixels are moving line by line Now it look like this:

https://cloud.hawke.pl/index.php/s/xpap2SQmJkgzaQ5

[fotosettore]

64x64 video http://www.homoandroidus.com/github/pxmatrix/VID-20181229-WA0068.mp4

64x32 (sorry in video i say 42 instead of 32) http://www.homoandroidus.com/github/pxmatrix/VID-20181229-WA0070.mp4

[houk001]

There is a movement in your video to. Line after some time go down by one pixel. On my both panels is go the same. I waited some time and red line goes to the half of size o panel and go up to the first line again.

Second blue line goes to the bottom of panel and goes up to the half of display again.

No other movement on panel.

[houk001]

Like this

[2dom]

@fotosettore ok thanks ... that does not make much sense.

Just a wild guess that either the latch or the output enable signal hast changed from activt low to active high or vice versa. Lets start with OE - could you try running the pattern test and modifying the latch function to this?

void PxMATRIX::latch(uint16_t show_time )
{

  digitalWrite(_LATCH_PIN,HIGH);
  digitalWrite(_LATCH_PIN,LOW);

  digitalWrite(_OE_PIN,HIGH); 
  delayMicroseconds(show_time);
  digitalWrite(_OE_PIN,LOW);
}

[fotosettore]

of course ... i try in few minutes

[houk001]

New video uploaded to cloud after change in latch function of course

[2dom]

@houk001 sorry ... cannot watch your videos ... loading forever :(

[fotosettore]

more lines of led on but does not works do you need a pic ?

[houk001]

Download it and then watch. VLC or similar is working

[2dom]

ok ... lets try changing the latch pin polarity

void PxMATRIX::latch(uint16_t show_time )
{

  digitalWrite(_LATCH_PIN,LOW);
  digitalWrite(_LATCH_PIN,HIGH);

  digitalWrite(_OE_PIN,LOW); 
  delayMicroseconds(show_time);
  digitalWrite(_OE_PIN,HIGH);
}

[fotosettore]

now ... "half" works :-)) it needs video please wait

[houk001]

Some progress :DDD video uploaded

[2dom]

@houk001 Still cannot watch those videos ... download times 10min+

[fotosettore]

void PxMATRIX::latch(uint16_t show_time ) {
digitalWrite(_LATCH_PIN,LOW); digitalWrite(_LATCH_PIN,HIGH);

digitalWrite(_OE_PIN,LOW); delayMicroseconds(show_time); digitalWrite(_OE_PIN,HIGH); } made this effect: http://www.homoandroidus.com/github/pxmatrix/VID-20181230-WA0001.mp4

[houk001]

https://youtu.be/fZrK874I-EU

[2dom]

Try

void PxMATRIX::latch(uint16_t show_time )
{
digitalWrite(_LATCH_PIN,LOW);
digitalWrite(_LATCH_PIN,HIGH);
delayMicroseconds(10);
digitalWrite(_OE_PIN,LOW);
delayMicroseconds(show_time);
digitalWrite(_OE_PIN,HIGH);
delayMicroseconds(10);
}

[2dom]

@houk001 Great ... that works! Very colorful :)

[fotosettore]

no changes with last void

[houk001]

Yes, no change with delays

[2dom]

try increasing the delay to 100us

[houk001]

Still the same.

[2dom]

Hm .. ok ... will have to think about it (and get some sleep). Thanks for your help ... I think we got somewhere !

[2dom]

uh ... one last try .. what about this ?

void PxMATRIX::latch(uint16_t show_time )
{
digitalWrite(_LATCH_PIN,HIGH);
digitalWrite(_LATCH_PIN,LOW);

digitalWrite(_OE_PIN,LOW);
delayMicroseconds(show_time);
digitalWrite(_OE_PIN,HIGH);
}

[fotosettore]

completely stopped with some pixel on

[houk001]

A step back with first high. No more animated right to left movement.

[2dom]

ok then ... another day. Cheers!

[fotosettore]

thanks for your support. now problems is emerged i hope it will be solved . have a nice night

[houk001]

Thanks from me too, i think that we are close to success :D