Voting resources, early voting, and poll worker information - VOTE. ... Adafruit is open and shipping.
0

32 x 32 LED matrix not working
Moderators: adafruit_support_bill, adafruit

Please be positive and constructive with your questions and comments.

32 x 32 LED matrix not working

by veedub88 on Mon Sep 14, 2020 1:12 am

Hello, I am having an issue with a 32 x 32 LED matrix that I just purchased. I am using the Adafruit RGB Matrix shield with a brand new Arduino Uno. I thought my old arduino might have been the culprit so I bought a new one and I am having the same results. If I program it with some of the example 16x32 programs (testshapes_16x32 or testcolors_16x32) it sorta works (orientation is sorta off) but the 32x32 programs just give me garbage.
On the attached pictures, pic1 is running the 32x32 textshapes and shows just lines without the power supply turned on, if I turn it on I get nothing. The other pic is running the 16x32 testshapes and it sorta works. This is a straight forward setup, just the shield plugged into an arduino.
Any ideas on what could be wrong?
Attachments
pic2.jpg
pic2.jpg (383.67 KiB) Viewed 216 times
pic1.jpg
pic1.jpg (436.62 KiB) Viewed 216 times
veedub88
 
Posts: 9
Joined: Tue Jun 19, 2012 2:15 pm

Re: 32 x 32 LED matrix not working

by veedub88 on Thu Sep 17, 2020 12:54 pm

Anyone? Is it just maybe a defective led matrix?
veedub88
 
Posts: 9
Joined: Tue Jun 19, 2012 2:15 pm

Re: 32 x 32 LED matrix not working

by veedub88 on Tue Sep 22, 2020 12:37 am

Hello Tech support?
veedub88
 
Posts: 9
Joined: Tue Jun 19, 2012 2:15 pm

Re: 32 x 32 LED matrix not working

by adafruit_support_carter on Mon Sep 28, 2020 12:41 pm

Please post a photo showing the soldering job on the RGB Matrix Shield headers pins and matrix connector header pins.

adafruit_support_carter
 
Posts: 17112
Joined: Tue Nov 29, 2016 2:45 pm

Re: 32 x 32 LED matrix not working

by veedub88 on Tue Sep 29, 2020 1:47 am

Hello, here are a couple of pictures. I retouched all of the solder joints on the matrix shield and that didn't help.
Attachments
20200928_223159.jpg
20200928_223159.jpg (342.41 KiB) Viewed 143 times
20200928_222001.jpg
20200928_222001.jpg (268.03 KiB) Viewed 143 times
20200928_221923.jpg
20200928_221923.jpg (308.88 KiB) Viewed 143 times
veedub88
 
Posts: 9
Joined: Tue Jun 19, 2012 2:15 pm

Re: 32 x 32 LED matrix not working

by veedub88 on Tue Sep 29, 2020 1:47 am

Couple more pictures.
Attachments
20200928_222847.jpg
20200928_222847.jpg (301.61 KiB) Viewed 143 times
20200928_222842.jpg
20200928_222842.jpg (318.86 KiB) Viewed 143 times
veedub88
 
Posts: 9
Joined: Tue Jun 19, 2012 2:15 pm

Re: 32 x 32 LED matrix not working

by adafruit_support_carter on Tue Sep 29, 2020 2:04 pm

Try powering the matrix through the shield instead of directly connected to the bench supply.

adafruit_support_carter
 
Posts: 17112
Joined: Tue Nov 29, 2016 2:45 pm

Re: 32 x 32 LED matrix not working

by veedub88 on Wed Sep 30, 2020 1:03 am

I tried that with the same results.
veedub88
 
Posts: 9
Joined: Tue Jun 19, 2012 2:15 pm

Re: 32 x 32 LED matrix not working

by adafruit_support_carter on Wed Sep 30, 2020 11:18 am

Please post a photo of that setup. Wondering if there might be a GND connection issue somewhere throwing off the signal levels to the matrix.

adafruit_support_carter
 
Posts: 17112
Joined: Tue Nov 29, 2016 2:45 pm

Re: 32 x 32 LED matrix not working

by veedub88 on Wed Sep 30, 2020 11:19 pm

Here is the setup
Attachments
20200930_200412.jpg
20200930_200412.jpg (392.31 KiB) Viewed 117 times
veedub88
 
Posts: 9
Joined: Tue Jun 19, 2012 2:15 pm

Re: 32 x 32 LED matrix not working

by adafruit_support_carter on Thu Oct 01, 2020 12:14 pm

Thanks. You've got input power connected to the power output. The terminal block on the shield are for powering the matrix. Connect the matrix power to those as seen here:
https://cdn-shop.adafruit.com/970x728/2601-02.jpg
and then apply the input power to the UNO's barrel connector.

adafruit_support_carter
 
Posts: 17112
Joined: Tue Nov 29, 2016 2:45 pm

Re: 32 x 32 LED matrix not working

by blnkjns on Fri Oct 02, 2020 5:18 am

This won't work on an UNO. For a 16x32 matrix you need 1.5 kB of RAM, now you need 3kB, which does not fit. Get a MEGA or a M0 Express.

blnkjns
 
Posts: 19
Joined: Fri Oct 02, 2020 3:33 am

Re: 32 x 32 LED matrix not working

by adafruit_support_carter on Fri Oct 02, 2020 12:43 pm

Hmmm. 32x32 *used* to work. But it was def a close fit. I've passed this on so the lib devs can take a look and see what might be up.

The product page for the shield mentions this will work "possibly", so not sure if maybe something has changed with the library to push that over the edge for an UNO.

adafruit_support_carter
 
Posts: 17112
Joined: Tue Nov 29, 2016 2:45 pm

Re: 32 x 32 LED matrix not working

by pburgess on Sat Oct 03, 2020 12:55 am

It might be a function of single- vs double-buffering. I’ll need to dig deeper this weekend and see what the Uno RAM situation is. There’s also a phenomenon where the Arduino core library tends to get incrementally bloatier over time…what used to (barely) fit in RAM might no longer be the case. Again, will require more probing, I’ll respond with results when I have them.

pburgess
 
Posts: 4062
Joined: Sun Oct 26, 2008 2:29 am

Re: 32 x 32 LED matrix not working

by pburgess on Sat Oct 03, 2020 7:36 pm

Can confirm: the only option that fits on the Arduino Uno anymore is 32x16, single-buffered. Double-buffered at that size, or anything 32x32, no longer fits. This is due to gradual incremental bloat in the Arduino core and/or the RGBmatrixPanel and Adafruit_GFX libraries.

Some options:
1. If you absolutely, positively MUST have this working on an Arduino Uno, you might be able to use an earlier version of the Arduino IDE and aforementioned libraries. I have no guidance to offer as to when each of these pieces crossed some critical threshold, and solving such a puzzle would entail an inordinate amount of work, I don’t recommend it.
2. If you need this on an AVR (for 5V GPIO or whatever) but not Uno/328P specifically, Arduino Mega has sufficient RAM for this. (Arduino Leonardo, despite having a little extra RAM, is NOT compatible with the library due to that board’s pinout.)
3. If you don’t need 5V GPIO, consider an ARM-based board, e.g. Metro M0.

I’ll be updating the guide to discourage use of these matrices on Arduino Uno going forward.

pburgess
 
Posts: 4062
Joined: Sun Oct 26, 2008 2:29 am

Please be positive and constructive with your questions and comments.