Rapberry Pi4 custom Display Problem

[TRyan]

Hello,

in the past (Raspberry Pi 2B, 3B, 3B+) I used a custom Display with a resolution of 480x640.

To use the display I used this config in the config.txt.

hdmi_ignore_edid=0xa5000080
hdmi_group=2
hdmi_mode=87
hdmi_cvt=464 618 65 1 1 0 0
hdmi_drive=1
dtoverlay=vc4-fkms-v3d

I tried this configuration with the Raspberry pi 4, but the display shows nothing.
When I use: hdmi_safe=1 the Display is showing something but the resolution is wrong.

Did the configuration from the display change by the Rasoberry Pi4?

Greetings

Tobias

[jamesh]

I think you need to remove this line from config.txt

dtoverlay=vc4-fkms-v3d

The VC4 fkms is replaced by v3d-fkms-v3d on the Pi4. Which should be there already in the [pi4] section.

[TRyan]

Hi Jamesh,

thanks for your quick replay.

I removed the line from the config.txt.

But still the same. When I use the same SD-Card in a Raspberry 3B+ the Display works.

Thanks for your help

Greetings

[jamesh]

Ensure you are using HDMI 0, or make the same config.txt entries available on HDMI1

e.g.

hdmi_group:0=2
hdmi_group:1=2

[TRyan]

Hi Jamesh,

thanks for your replay.

I change the config to:

hdmi_ignore_edid:0=0xa5000080
hdmi_group:0=2
hdmi_mode:0=87
hdmi_cvt:0=464 618 65 1 1 0 0
hdmi_drive:0=1

But no difference.
When I at hdmi_safe:0=1, the Display show the console, but die resolution is wrong and the display ist not fillied
Thanks for your help

Greetings Tobias

[TRyan]

Hi,

it seems that the command hdmi_cvt maks the problem.

I use now:

hdmi_timings

and it works.

Now I must find out the right timmings for my display.

Thanks for your help.

Greetings Tobias