Recently purchased received yesterday. Cannot get it to work properly. Only get half of the LEDS to work in two rows of 8, top and bottom and can only get red and green, no blue. Used examples and checked cabling 3 times, used different board still the same. Have 5V, 3 amp power supply to led array.
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Assume this is the panel you have.
Can you provide more information on how you have it set up (a pic maybe), what controller you are using, etc ?? 13 GPIO’s is a large number to get right. It specifies 5V/2A supply, but that assumes not all leds will be on at full brightness. If all 512 were on at full brightness it would need over 10 amps.
Suggest you cut it back to very basic in the software. Try to turn just one LED on or off. Examine the Adafuit library to see what it is doing and how it turns the LEDs on and off and try to emulate that for just one LED in your software. I never trust these libraries until they have proven to work.
But hard to say why it is not working without more information.
Regards
Jim
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HI James
Trying it with A MEGA now, will let you know. Pretty sure I have all 13 lines correct. Already tried individual pixels with no luck so I don’t think it is power supply. Ultimately the reason I got this was to provide specific wavelength of light for small plants in scientific research at Adelaide Uni. I will need to illuminate all of the LEDS at full strength. Is it safe to use a 10 amp supply if such exists at 5 v. If so my next option is to use a Pi 4B with the special hat for the array.
Cheers
Steve
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The best source for a 5V supply is an old PC. AT power supplies were often rated at 20A for 5V.
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OK I have a few.
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Hi Steve
I have a MeanWell 5V @ 14A supply which is not too large physically and won’t break the bank.
MeanWell have been around a long time and are reputable enough to have survived the current cheap and cheerful competition.
Jaycar are offering this one at $57.95. Cat no MP3289. A little more expensive that when I bought mine but still pretty reasonable.
Cheers Bob
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@steve103761 The 10A comes from 20mA x 512 = 10.24A. Full bright.
Looking through the comments in the library it says the pinouts for a ATMega will be different. This is not mentioned in the DFRobot Wiki page.
Looking further through the library, in my opinion, it is a really complex way to turn on and off RBG LEDs. Without a circuit schematic it is hard to understand what it is doing. But I think it needs to write to the display often to keep the LEDs lit, further complicating the process. The comments also mention a way of doing this I am not familiar with. It would be interesting to know if anyone has actually got one of these to work with the DFRobot Wiki advice.
All the best
Jim
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Thanks Jim, Ill let you know.
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Hi Steve,
Let us know how you go. A picture of your setup and the code you’re running can also go a long way for us to get your project back on the road.
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OK will do. In the meantime not sure why I did not try the GlowBit matrix…seems simpler.
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Hi Jack
Got it working fine with the Mega. Suggest you direct customers to this site: https://learn.adafruit.com/32x16-32x32-rgb-led-matrix?view=all
Cheers
Steve
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Hi Steve,
That a good reference, I will be sure to pass on if someone needs help in the future. Otherwise there is no better place for this information to be available than in this forum post for this product.
Thanks Steve!
Sam
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Hi Sam,
I have got the RGB LED panel to work for our experiment, but it may not be bright enough. I wonder if you could recommend a brighter RGB array?
Cheers
Steve
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Hi Steve,
Unfortunately these kinds of displays (at the hobby level) are pretty dim.
Something like the GlowBit Matrix might be a bit brighter
Whats your application?
In Thredbo it looked like they had a similar screen (LED HUB75 matrix) but the area was shaded, no strong sources of light behind the display giving it good contrast, but it still wasnt visible from a long range or super clear unless you were standing normal to the screen.
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HI Liam
It is to support to some extent plant growth on plates and to switch on genes that respond to blue light, therefor we are using RGB LEDS. Leds can be quite close to the little plants to get the required intensity. I did look at the GlowBit 8x8 matrix and from the description I assume they are much brighter than the 16 x 32 matrix from Adafruit? I will go for an order to trial them if you think they would be brighter. I would probably link two or three together with adequate power supply.
Cheers
Steve
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Hi Sam,
The GlowBits may be brighter than the Adafruit matrix.
To run 3 of them you would be looking at needing a 6A power supply to power them all.
I am curious if you are still running the Adafruit Matrix with a 2A supply?
Having a look through the specs for them it looks it requires at least 2.5A and we recommend a 4A supply for it.
Not being able to supply them with the required current might be why they aren’t as bright as expected.
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Hi Aaron,
I am running them from a 4 Amp supply currently and I also have a 14 Amp supply ready to go.
Cheers
Steve
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Hi Aaron
Would it be possible to run the Glowbits 8 x 8 matrix with the Adafruit Matrix Portal M4 microprocessor. It would appear to have sufficient speed and memory, just wondering if the Adafruit Neopixel Library will work with this board. I would prefer not to use a Pi.
Cheers
Steve
@steve103761 the Neopixel library ought to work - it might just take some due diligence to make sure the LEDs are arranged in the same pattern (rows or zigzag)
If i recall correctly, the adafruit library as options you can set to address either type though.
The M4 is more than ample for the task.
