Waveshare 4.3" hdmi with orangepi/nanopi?

[arjepsen]

Hey.

I have a waveshare 4.3" 480x272 screen, that I'm trying to get to work with my orange pi zero +2, or nanopi M1 plus.

However, I can't get the screen to show the right resolution - that only seems possible on my raspberry pi (which I don't want to use for this project).

I've been running over all the (little) info I can find, and it seems to be a general problem to get hdmi working if the screen edid is a bit flaky - is this still the case, or is it possible to get this combination of opi/nanopi to work on this display?

 

Regards.

Anders

[jernej]

Can you give link to your exact model? Looking at waveshare site, 4.3" 480x272 LCD has only 40 pin connector - this will not work with anything but RPi. Or did you mean 4.3" 800x480 HDMI monitor? This one should work in theory. There is also 4.3" 800x480 DSI one which I'm not sure if it can work or not.

[arjepsen]

this one:

https://www.waveshare.com/wiki/4.3inch_HDMI_LCD

V2 in my case.

[jernej]

Please provide EDID blob (most probably at /sys/class/drm/card0-HDMI-A-1/edid) and content of /sys/kernel/debug/clk/clk_summary

[arjepsen]

Here's the summary.

I'm a bit uncertain about whether "cat /sys/class/drm/card0-HDMI-A-1/edid" is what you want - I've been messing with it quite a bit in various edid editors, so I also attach a bin file I got from one of them here. 

 

edidblob clk_summary edid.bin

[jernej]

Everything seems to be in order, assuming edid is correct. Refresh rate is pretty strange - 65.681 Hz. Clocks are correctly set according to edid - 32 MHz. I have another waveshare HDMI screen (1024x600) where pixel clock is also 32 MHz and it works fine. Not sure what to suggest, except that you can try to override edid with your own.

[arjepsen]

That's the point  - the edid is not correct. On the raspberry pi it is overriden to 480x272@60 by these lines in config.txt:

hdmi_group=2

hdmi_mode=87

hdmi_cvt 480 272 60 6 0 0 0

But this does not work in armbianEnv.txt

 

I have been trying to override the edid , but have so far not been successful in making one that doesn't throw errors on boot, and it is stuck at 800x480.

 

[jernej]

If you can manage to prepare appropriate edid binary, you can supply it to kernel according these instructions: https://wiki.archlinux.org/index.php/kernel_mode_setting#Forcing_modes_and_EDID If it works, you can in some cases also write that permanently into your screen. Wrong EDID is worst kind of issue. I never actually had such problems, so I'm not sure how to edit edid.

[arjepsen]

ok. Thanks for your input anyway. :-)

[ej0rge]

On 4/12/2021 at 1:01 PM, jernej said:

Can you give link to your exact model? Looking at waveshare site, 4.3" 480x272 LCD has only 40 pin connector - this will not work with anything but RPi. Or did you mean 4.3" 800x480 HDMI monitor? This one should work in theory. There is also 4.3" 800x480 DSI one which I'm not sure if it can work or not.

 

Minor quibble -- You can get the gpio displays to work, but you need a dtoverlay and you will probably have to write it yourself - at a minimum you'll have to edit an existing one unless there is already one available for your exact configuration.