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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
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Documentation for --led-pwm-dither-bits=<0..2> ? #1193

Open marcmerlin opened 4 years ago

marcmerlin commented 4 years ago

https://github.com/hzeller/rpi-rgb-led-matrix/blob/master/examples-api-use/README.md mentions

        --led-pwm-dither-bits=<0..2> : Time dithering of lower bits (Default: 0)

which is all I was able to find. However, it gives me a massive performance boost. I go from about 160Hz to almost 400Hz between 0 and 2, and I'm not sure I see much of a visible difference.

@hzeller , Is there documentation somewhere on the pros and cons of that option given the pretty massive impact it has on refresh rate?

If that helps, this is what I run on a Pi4: /rpi-rgb-led-matrix/examples-api-use/demo --led-gpio-mapping=regular --led-rows=64 --led-cols=128 --led-row-addr-type=0 --led-show-refresh --led-slowdown-gpio=2 --led-pwm-bits=7 --led-panel-type=FM6126A --led-parallel=3 --led-chain=1 --led-pwm-lsb-nanoseconds=100 --led-pwm-dither-bits=2 -D10 it seems to run fine, and I love the refresh speed that is more than twice as fast

652436962 commented 2 years ago

when i use zero( -- led-pwm-lsb-nanoseconds=100 --led-pwm-dither-bits=2 ) , it can.t display. why?