Led matrix missing rows

EL Wire/Tape/Panels, LEDs, pixels and strips, LCDs and TFTs, etc products from Adafruit

Moderators: adafruit_support_bill, adafruit

Please be positive and constructive with your questions and comments.
User avatar
ldzhamov
 
Posts: 10
Joined: Sun Dec 11, 2022 9:05 pm

Led matrix missing rows

Post by ldzhamov »

Hi,

I've been working on a scoreboard project using led matrix and adafruit RGB matrix hat and Raspberry Pi 4. It's all been working well until a few days ago when I was making final testing and left it working for a few hours. It appears that half of the LED matrix rows are not working. I'm seeing 2 rows on, 2 off, 2 on etc.. It happened gradually actually. I started noticing the now missing rows going off and on. After about an hour they've disappeared for good. I went through the forum and tried a lot of options and configurations. No luck so far.
Screenshot_20230330-181657.png
Attachments
Screenshot_20230330-181657.png
Screenshot_20230330-181657.png (974.64 KiB) Viewed 246 times

User avatar
mikeysklar
 
Posts: 13936
Joined: Mon Aug 01, 2016 8:10 pm

Re: Led matrix missing rows

Post by mikeysklar »

Can you show a photo of any soldering you have done and the connections?

What power supply are you using for the matrix?

Is the behavior the same with demo code?

User avatar
ldzhamov
 
Posts: 10
Joined: Sun Dec 11, 2022 9:05 pm

Re: Led matrix missing rows

Post by ldzhamov »

I'm using Dell F220P-00 power supply with 12V to 5V DC to DC converter.
It behaves the same way with the demo code. There is a demo example with a pixel that you can move around. When I move it down it "jumps" through the missing rows.
Attachments
PXL_20230405_033324042.MP.jpg
PXL_20230405_033324042.MP.jpg (109.58 KiB) Viewed 225 times
PXL_20230405_033155860.MP.jpg
PXL_20230405_033155860.MP.jpg (126.28 KiB) Viewed 225 times
PXL_20230405_033300382.MP.jpg
PXL_20230405_033300382.MP.jpg (997.45 KiB) Viewed 225 times

User avatar
mikeysklar
 
Posts: 13936
Joined: Mon Aug 01, 2016 8:10 pm

Re: Led matrix missing rows

Post by mikeysklar »

Thank you for the photos.

Your ribbon cable appears to be reversed.
IMG_1163.jpeg
IMG_1163.jpeg (902.19 KiB) Viewed 222 times
I see the quality jumper is included in your soldering. Did you configure the rgbmatrix setup script for quality mode vs convenience mode when selecting the options?

User avatar
ldzhamov
 
Posts: 10
Joined: Sun Dec 11, 2022 9:05 pm

Re: Led matrix missing rows

Post by ldzhamov »

Reverting the ribbon cable didn't fix the issue. I've set it up using the quality settings.

User avatar
mikeysklar
 
Posts: 13936
Joined: Mon Aug 01, 2016 8:10 pm

Re: Led matrix missing rows

Post by mikeysklar »

Make sure the red line on your ribbon (pin1) is aligned the same as the product photos page on both ends (panel and connector).

https://learn.adafruit.com/adafruit-rgb ... on-1745231

If you setup your board for quality mode solder in the jumper wire. In the original photos I saw the red jumper, but it was not soldered. The next photo the jumper was not there at all.
First, you need to solder a jumper wire between GPIO4 and GPIO18 on the Bonnet or Hat board.

User avatar
ldzhamov
 
Posts: 10
Joined: Sun Dec 11, 2022 9:05 pm

Re: Led matrix missing rows

Post by ldzhamov »

The red jumper has always been there and soldered. I believe it's missing in the photo in your reply.
Screenshot_20230410-124334.png
Screenshot_20230410-124334.png (442.68 KiB) Viewed 205 times
PXL_20230410_163619026.MP.jpg
PXL_20230410_163619026.MP.jpg (96.31 KiB) Viewed 205 times

User avatar
mikeysklar
 
Posts: 13936
Joined: Mon Aug 01, 2016 8:10 pm

Re: Led matrix missing rows

Post by mikeysklar »

All the connections look correct.

This is likely a power supply issue. Do you have a 5v 4A or higher current power source you can try? I see your 12v converter has appropriate ratings, but we often have issues with various alternative power supplies. This would also align with the slow decline in resolution you had observed as rows would start to go away as it was used longer.

User avatar
ldzhamov
 
Posts: 10
Joined: Sun Dec 11, 2022 9:05 pm

Re: Led matrix missing rows

Post by ldzhamov »

I tried another power supply (see attachment). Same behaviour.
Attachments
PXL_20230415_014700095.MP~2-min.jpg
PXL_20230415_014700095.MP~2-min.jpg (823.41 KiB) Viewed 193 times

User avatar
mikeysklar
 
Posts: 13936
Joined: Mon Aug 01, 2016 8:10 pm

Re: Led matrix missing rows

Post by mikeysklar »

Alright, this new power supply also has good specs so we can rule that out.

What is the adafruit part# for the panel you have?

Which arguments are you passing to the demo code?

User avatar
ldzhamov
 
Posts: 10
Joined: Sun Dec 11, 2022 9:05 pm

Re: Led matrix missing rows

Post by ldzhamov »

The manel part is : 64x32 RGB LED Matrix - 6mm pitch PID: 2276

Arguments
--led-gpio-mapping=adafruit-hat-pwm
--led-rows=32
--led-cols=64

I've played around with changing some default values like: slowdown gpio, brightness, PWM bits, refresh rate.
No change, same result.

User avatar
mikeysklar
 
Posts: 13936
Joined: Mon Aug 01, 2016 8:10 pm

Re: Led matrix missing rows

Post by mikeysklar »

CLI arguments are good.

I'm pretty sure this is a convenience vs quality mode issue.

You can resolder the red jumper which does not have enough solder as I can see the exposed via pad and try the demo again (still in high quality mode).

or

Cut the red jumper and re-run the configuration script for convenience mode.

User avatar
ldzhamov
 
Posts: 10
Joined: Sun Dec 11, 2022 9:05 pm

Re: Led matrix missing rows

Post by ldzhamov »

I've tried removing the jumper and reconfiguring using convenience settings. Same result.

User avatar
mikeysklar
 
Posts: 13936
Joined: Mon Aug 01, 2016 8:10 pm

Re: Led matrix missing rows

Post by mikeysklar »

With the quality jumper removed did you re-run the script to set convenience mode and adafruit-hat?

Code: Select all

sudo bash rgb-matrix.sh
The arguments will change when running the demo.

Only use (dropping the adafruit-hat-pwm flag):

Code: Select all

sudo ./demo -D0 --led-cols=64 --led-rows=32 

User avatar
ldzhamov
 
Posts: 10
Joined: Sun Dec 11, 2022 9:05 pm

Re: Led matrix missing rows

Post by ldzhamov »

Yes, that's what I did.

Locked
Please be positive and constructive with your questions and comments.

Return to “Glowy things (LCD, LED, TFT, EL) purchased at Adafruit”