RP4B 2GB | HDMI to Samsung 4K TV not detected

oswyevega

So, I've been struggling with this for 2 days. Tried every configuration I can get on internet and the forums, but nothing works. My TV model is un60au8000, the thing is I got it working the first day, but the next day the TV didn't recognize the RB pi anymore.

I'm using a Samsung monitor for testings but despite it works on the monitor it doesn't on the TV. I want this build for Steam Link.

Addison

Unplug the HDMI cable from the Pi and plug it into the other HDMI output on your Pi.

See if that works.

mitu

Limit the resolution to 1080p - see https://retropie.org.uk/docs/Pi4/#issues-using-a-4k-tv - and make sure you're powering on the Pi after the TV is on.

oswyevega

@mitu Thanks for your response, still not working, it is working on the monitor but not the TV.

I added these settings as suggested and turned on the TV and set the source on HDMI 3, before power on the RB

hdmi_group=1
hdmi_mode=16
hdmi_max_pixel_freq:0=200000000
hdmi_max_pixel_freq:1=200000000
gpu_mem=320M

This is the original set of configs in the config.txt

dtparam=audio=on
camera_auto_detect=1
display_auto_detect=1
dtoverlay=vc4-kms-v3d
max_framebuffers=2
disable_overscan=1
otg_mode=1
arm_boost=1

oswyevega

@addison Not working. I'm using the closest port to the power supply port, but also tested in the other port, and it didn't work.

mitu

Are you even using RetroPie ? Looks like you're using the newer Raspi OS (11), which is not yet supported by RetroPie.

oswyevega

@mitu I switch the OS to test if it was a Retropie issue. I will install the OS again and test with these settings. Let you know if it works. Thanks again for your support!

oswyevega

@mitu I installed Retropie 4.7.1 from Raspberry Pi Imager. This is my current config.txt settings:

# uncomment if hdmi display is not detected and composite is being output
hdmi_force_hotplug=1

# uncomment to force a specific HDMI mode (this will force VGA)
hdmi_group=1
hdmi_mode=16
gpu_mem=320M
hdmi_max_pixel_freq:0=200000000
hdmi_max_pixel_freq:1=200000000

# Enable audio (loads snd_bcm2835)
dtparam=audio=on

[pi4]
# Enable DRM VC4 V3D driver on top of the dispmanx display stack
dtoverlay=vc4-fkms-v3d
max_framebuffers=2

[all]
#dtoverlay=vc4-fkms-v3d
overscan_scale=1

Again, working on my monitor but not on my TV. I turned on my tv first, and then power on the raspberry. Any advice ?

mitu

You should remove the gpu_mem setting, it's no use on a Pi4. Also, you've set the resolution explicitly, there's no need to add the other configurations (hdmi_max_pixel_freq).

Does your TV support 1080p ? If you run tvservice -m CEA, what's the output ? You can run the command via SSH and copy the output.

oswyevega

@mitu

pi@retropie:~ $ tvservice -m CEA
Group CEA has 4 modes:
           mode 4: 1280x720 @ 60Hz 16:9, clock:74MHz progressive 
  (prefer) mode 16: 1920x1080 @ 60Hz 16:9, clock:148MHz progressive 
           mode 95: 3840x2160 @ 30Hz 16:9, clock:297MHz progressive 
           mode 97: 3840x2160 @ 60Hz 16:9, clock:594MHz progressive

Current config.txt

# uncomment if hdmi display is not detected and composite is being output
hdmi_force_hotplug=1

# uncomment to force a specific HDMI mode (this will force VGA)
hdmi_group=1
hdmi_mode=16

# Enable audio (loads snd_bcm2835)
dtparam=audio=on

[pi4]
# Enable DRM VC4 V3D driver on top of the dispmanx display stack
dtoverlay=vc4-fkms-v3d
max_framebuffers=2

[all]
#dtoverlay=vc4-fkms-v3d
overscan_scale=1

mitu

Though the list of supported modes is a bit short, 1080p seems supported. Other than double checking the cable, no idea at this time.

oswyevega

@mitu Thank you again for the support. Yeah, is a mystery to me as well since I got it working the first day with Steam Link and everything looked good. So don't know what changed from day one to day 2.

I'll review the HDMI cable and the power supply. Maybe that is the issue.

busywait

@oswyevega
Try putting this overclock line in to /boot/config.txt

core_freq=650

It overclocks the "GPU", the core that is involved in putting data onto the HDMI cable. That change fixed a blank screen on my 4K PC monitor after I switched to the new (bullseye) Raspberry Pi OS.

Even without that change the blank screen went away when I used the official Raspberry Pi monitor cable - probably the best solution :)

oswyevega

@busywait I'll try this one and let you know the results! I also ordered the official HDMI cable and the official power supply, from Amazon, just to make sure!

Thanks for the advice! :)