Increase refresh speed - waveshare 6inch HD e-Paper HAT

[serafimdasaudade]

Hi,
I'm testing this lib.
I'm using the vnc desktop, and it working. But I start notice that e-paper take a lot of time to update +- 5sec.
The command I'm using:
poetry run papertty --driver it8951 vnc --display 1 --password raspberry --sleep 0.1 --rotate 0

I would like to improve the refresh rate. Any tips?

Cumps,

[joukos]

Which RPi are you using? To get decent speeds with a display this size an RPi3b+ / RPi4 might be best. There's a lot of room for optimization in general, though.

[serafimdasaudade]

I'm using a RPI 4.
I'm doing some code teaks, but with no noticeable improvements.

[serafimdasaudade]

Which RPi are you using? To get decent speeds with a display this size an RPi3b+ / RPi4 might be best. There's a lot of room for optimization in general, though.

Hi, Do you got some tips. Help me go to the correct direction?

Cumps,

[chi-lambda]

You can set the max_speed_hz (driver_it8951.py:183) to something higher. 18 MHz worked for me, but it stopped responding after running it for a few hours. Could be unrelated though. There was no permanent damage as far as I can tell. VNC uses the grayscale instead of black-and-white mode, which uses more data (I think it was a factor of four because even b/w uses 2 bits per pixel) and is therefore slower. You could add another filtering step to turn it into a black-and-white picture after papertty.py:369 to speed things up if you can accept the loss of quality.