search

hzeller / rpi-rgb-led-matrix

Controlling up to three chains of 64x64, 32x32, 16x32 or similar RGB LED displays using Raspberry Pi GPIO
GNU General Public License v2.0
3.67k stars 1.17k forks source link

RPI 3B+ 8 X modules P5 + PowerSupply 5V60A + Adapter passive 3 = Fickering #790

Open AliDem opened 5 years ago

AliDem commented 5 years ago

Hello, I do not understand why? These is my command line options, I use Raspbian list (without GUI) isolcpus = 3 is enabled. I tried all the combinations but I still have the same problem. I tried to change Makefile "-DFIXED_FRAME_MICROSECONDS=XXXX", improve little bit, reduce the flickering but the problem is always the same. I Can't use gpio-slowdown to 1 or 0.

--led-rows=32 --led-cols=32 --led-chain=8 --led-parallel=2 --led-multiplexing=2 --led-pixel-mapper "U-mapper" --led-slowdown-gpio=2 --led-pwm-lsb-nanoseconds [100-300] --led-scan-mode=[0,1] --led-pwm-bits=[8,9,10,11] --led-pwm-dither-bits=[0,1,2]

https://www.ali-demir.com/video-1554219170.mp4

you will see the refresh of the video on the door, is not stable.

Thank you in advance,

jaygarcia commented 5 years ago

hi @gamukeat, have you tried a more optimized distro like DietPi?

leoceto commented 3 years ago

I do have the exact same behavior on the RPI 3B+, I struggle to find the right parameters while it is working well on RPI2 et RPI4.

Any ideas to optimize it on RPI 3B+ ? It looks like it is between gpio-slowdown 2 and 3 or 1 or 2....

jaygarcia commented 3 years ago

@leoceto did you follow the above isolcpus = 3 param? The flicker depends on a ton of factors, including things like locks to any threads you might be running to feed the buffer for this library as well as overheating. Is your 3B+ actively cooled?

leoceto commented 3 years ago

Hello, yes i put the isolcpus = 3 param, I manage more or less to have almost no flicker by decreasing the pwm-bits and increasing the pwm-dither-bits while limiting the refresh rate with a gpio-slowdown = 2, but that's a pity to decrease the performance for that....