64x32 RGB LED Matrix Adafruit RGB Matrix HAT + RTC

[blakebr]

Hi,

I just purchased the following:
64x32 RGB LED Matrix - 4mm pitch - Product ID: 2278
Adafruit RGB Matrix HAT + RTC for Raspberry Pi - Mini Kit - Product ID: 2345

While running the python samples I am getting strange results. This is my command line:

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sudo python3 graphics.py --led-slowdown-gpio=1 --led-rows=32 --led-cols=64 --led-brightness=75

What the image does is load just fine. It is suppose to show for 10 seconds, then clear. What it does is load, show good for a couple seconds, show a jumble of LEDs lit, stabilize, show a jumble of LEDs, stabilize, turn off display.

I have a python program that shows time/date/etc. that runs fine at 100% brightness, but has intermitent jumble of LED at 10% brightness.

This is on a Raspberry Pi 3B+ with a fresh DS card and a fresh OS load.

I have a video. How do I make it available to you?

What am I doing wrong?

Bruce

[mikeysklar]

Bruce,

Post the video on google drive, youtube or any site you can drop us a link to.

I'm sorry if you mentioned this before, but are you using a 4A Adafruit power supply with this?

Are you running in "convenience" mode vs. "quality" mode?

[blakebr]

Mike,

"convenience" mode, 3 Amp power supply. Tried a 10 Amp, no change.

Bruce

[blakebr]

and a link:

https://drive.google.com/file/d/1K5sLiW ... sp=sharing

[mikeysklar]

Thank you for the video.

Those demos look like they are running correctly.

Is it that it is turning off or that is garbled when you lower the brightness that you are concerned about?

Is this on Bullseye or Buster (Buster - Legacy 32-bit Lite install is recommended).

[blakebr]

Mike,

This is what I get when I log in.

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Linux raspberrypi-LED-Clock 6.1.25-v7+ #1647 SMP Wed Apr 26 17:35:40 BST 2023 ar                                                                                                                     mv7l

The programs included with the Debian GNU/Linux system are free software;
the exact distribution terms for each program are described in the
individual files in /usr/share/doc/*/copyright.

Debian GNU/Linux comes with ABSOLUTELY NO WARRANTY, to the extent
permitted by applicable law.
Last login: Thu May  4 15:23:12 2023

From that I would guess I am using Bullseye. I am using whatever the Raspberry Pi org is loading to the DS cards when using their Windows application rpi-imager.exe. Not really in the mood to do a full reinstall.

The jittery display during the time.sleep(10) before the python program exits and turns off all the pixels.

Is there another setting besides --led_slowdown_gpio=1 that I can test out? I have tried =4 with no improvement.

Bruce

[mikeysklar]

You are most likely running Bullseye. The results of:

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uname -a

and

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cat /etc/os-release

would be the best way to confirm what you are running.

I have a Pi 3B+ and 64x64 with the RGB Bonnet so I’ll try running the same demos and let you know the results. I just setup an microSD with Pi OS legacy 32-bit Lite.

What you are describing as jittery might be the same as what the hzeller README calls flicker. I would install the #4 <—> #18 quality jumper and manually pass the following argument to the demo.

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--led-gpio-mapping=adafruit-hat-pwm

https://github.com/hzeller/rpi-rgb-led- ... ng-flicker

[blakebr]

Mike,

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pi@raspberrypi-LED-Clock:~ $ cat /etc/os-release
PRETTY_NAME="Raspbian GNU/Linux 11 (bullseye)"
NAME="Raspbian GNU/Linux"
VERSION_ID="11"
VERSION="11 (bullseye)"
VERSION_CODENAME=bullseye
ID=raspbian
ID_LIKE=debian
HOME_URL="http://www.raspbian.org/"
SUPPORT_URL="http://www.raspbian.org/RaspbianForums"
BUG_REPORT_URL="http://www.raspbian.org/RaspbianBugs"

[mikeysklar]

Yeah, definitely Bullseye current. Try that quality jumper and pwm flag first before we talk about rolling back to Buster.

[blakebr]

Mike,

Added jumper 4 to 18 and --led-gpio-mapping=adafruit-hat-pwm. No change.

Bruce

[mikeysklar]

I tried the cube demo (./demo -D0) and the graphics.py from the samples folder. Both ran fine and smooth for my 64x64 display. The only arguments I provide are row/col size. I am running Buster (not Bullseye).

Three thoughts.

1) Make sure you are running as root with 'sudo' in front of the commands to reduce flicker.

2) Confirm by running raspi-config that the sound and one-wire are disabled.

3) You can adjust pwm-bits.

--led-pwm-bits=(1…11) For long matrix chains you’ll probably need to use fewer PWM bits, sacrificing some color fidelity to improve refresh speed. Default is 11.

If the above does not effect things you will need to roll back to Buster. When using Image to setup a new microSD card hit:

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 choose OS --> Raspberry Pi OS --> Raspberry Pi OS (Legacy)

[blakebr]

Mike,

Thanks for all your help. However I don't feel like loading an old OS to make this thing work. I will keep checking the adafruit tutorial pages to see if the support software has been updated. I will stay with what I have and try as many work-arounds as I can find.

I believe not updating the software to be fully compatible with the current OS is a bad corporate decision. I bet there are many hobbyists who don't want to load an out-of-date OS with the risks of known/unknown security risks and other incompatibilities.

Bruce

[mikeysklar]

Bruce,

Running a current Pi OS would be ideal. I'll point out that the guide only claims support up to Buster.

We have a script that downloads the code and any prerequisite software. It works with the current Raspbian “Buster” (or earlier “Stretch”) operating system (either the Lite or Desktop version):

https://learn.adafruit.com/adafruit-rgb ... re-1745233

so maybe we can modify that once Bullseye is confirmed to work.

Recently the 32-bit Bullseye pulled a somewhat unexpected move and through in a 64-bit kernel into the update which has caused other issue in the guide world. Just one example of why it is so difficult to keep pace with the current release + updates.

I'll update mine to Bullseye and let you know if things work the same or I encounter issues.

[blakebr]

Mike,

Recently the 32-bit Bullseye pulled a somewhat unexpected move and through in a 64-bit kernel into the update which has caused other issue in the guide world. Just one example of why it is so difficult to keep pace with the current release + updates.

I admit I am not the brightest bulb on the tree... But an OS with a 64-bit kernel is NOT a 32 bit OS.

Thanks for your testing.

Bruce

[mikeysklar]

In March of this year that is what happened. A pure 32-bit install of Pi OS got a 64-bit default kernel update. A mix of 32-bit user space and 64-bit kernel space.

This is why I'm suspicious of issues between Buster --> Bullseye. I'll let you know what I find on my RGBMatrix.