Nothing on fhd-hdmi-screen

General Discussion
1

Hi *,

I have flashed a DietPI image to microSD with the Raspberry PI Imager - one for RPI-3B and one for RPI-4.

When both the microSD’s are inserted in the RPI and booted from, I end up without nothing on the HDMI connected screen. I can use SSH to do a login and make some config changes. But still - it is challenging to get the console working via usb-keyboard and fhd-hdmi-screen. Any suggestion?

With warm regards - Will

2

did you tried adjusting display settings using dietpi-config ?

1 Like
3

Yes - I tried with option 0. With that I get [FAILED] No DRM device has been found.

I also tried withdisplay_auto_detect=1andhdmi_force_hotplug=1in /boot/config.txt.

None of these seems to work.

At one point I achieved output in 640x480 - but changing that into 1920x1080 give me a black screen again.

Any other suggestions?

4

Can you check the following:

dmesg | grep -i hdmi
cat /sys/class/drm/card0-HDMI-A-1/status
1 Like
5

Below the requested output. Is this what you where looking for?

I also added the output of: cat /sys/class/drm/card?-HDMI*and cat /sys/class/drm/card?-HDMI*/status.

Perhaps this helps? :innocent:

=====

@DietPi:/home/will# dmesg | grep -i hdmi
[    0.000000] Kernel command line: coherent_pool=1M 8250.nr_uarts=1 snd_bcm2835.enable_headphones=0 cgroup_disable=memory numa_policy=interleave nvme.max_host_mem_size_mb=0 snd_bcm2835.enable_headphones=0 snd_bcm2835.enable_hdmi=0 snd_bcm2835.enable_hdmi=0 video=HDMI-A-1:640x480M@60D,margin_left=24,margin_right=24,margin_top=16,margin_bottom=16 video=HDMI-A-2:640x480M@60D,margin_left=24,margin_right=24,margin_top=16,margin_bottom=16 numa=fake=2 system_heap.max_order=0 smsc95xx.macaddr=D8:3A:DD:B3:95:3E vc_mem.mem_base=0x3f000000 vc_mem.mem_size=0x3f600000  root=PARTUUID=2538bb87-02 rootfstype=ext4 rootwait fsck.repair=yes net.ifnames=0
[    6.770529] [drm] forcing HDMI-A-1 connector on
[    6.774247] rc rc0: vc4-hdmi-0 as /devices/platform/soc/fef00700.hdmi/rc/rc0
[    6.776024] input: vc4-hdmi-0 as /devices/platform/soc/fef00700.hdmi/rc/rc0/input4
[    6.782804] input: vc4-hdmi-0 HDMI Jack as /devices/platform/soc/fef00700.hdmi/sound/card0/input5
[    6.784224] vc4-drm gpu: bound fef00700.hdmi (ops vc4_hdmi_ops [vc4])
[    6.785820] [drm] forcing HDMI-A-2 connector on
[    6.793007] rc rc1: vc4-hdmi-1 as /devices/platform/soc/fef05700.hdmi/rc/rc1
[    6.793150] input: vc4-hdmi-1 as /devices/platform/soc/fef05700.hdmi/rc/rc1/input6
[    6.801039] input: vc4-hdmi-1 HDMI Jack as /devices/platform/soc/fef05700.hdmi/sound/card1/input7
[    6.801583] vc4-drm gpu: bound fef05700.hdmi (ops vc4_hdmi_ops [vc4])

@DietPi:/home/will# cat /sys/class/drm/card0-HDMI-A-1/status
cat: /sys/class/drm/card0-HDMI-A-1/status: No such file or directory

@DietPi:/home/will#cat /sys/class/drm/card?-HDMI\*
cat: /sys/class/drm/card1-HDMI-A-1: Is a directory
cat: /sys/class/drm/card1-HDMI-A-2: Is a directory

cat /sys/class/drm/card?-HDMI\*/status
connected
connected
6

This is the config that gives you 640x480 output?

Can you change the resoution to 1920x1080 with dietpi-config and do the same again, please?

1 Like
7

Just found the root-cause (and fixed it): the cable was poorly connected – hence no image.

I now firmly attached the micro-hdmi cable and everything is working as expcted.

Thank you for your time and patience.

1 Like