No Video Output with Hdmi to Dvi Cable RPI 3 B+

1st Official Post

    Hi everyone!

    I am quite new to libreelec and have the follwing issue:


    I use a hdmi to dvi cable to connect the rpi3 b+ to my beamer. with the older rpi3 b it worked like a charm (with retropie). After installing the os (with a normal hdmi cable connected) i tried it with the hmdi>dvi cable which is giving me no output.

    I already tried this:

    Code
    mount -o remount,rw /flash

nano /flash/config.txt

    I then uncommented the hdmi_force_hotplug=1 But that didn't change a thing...Any suggestions here?

    Try to increase the config_hdmi_b o o s t parameter in config.txt (the word b o o s t is censored on this forum for some reason, so no spaces)

    • Official Post

    It is working without any option changes on LibreELEC. I have been tested it with Raspberry Pi 3B+, a HDMI cable and a HDMI to DVI adapter on a PC monitor. Make sure to first connect the display device, and then power on the Raspberry Pi. LibreELEC figures out, what display is connected, while booting.

    PS: It could be a PSU issue, too. The 3B+ needs more wattage compared to the 3B.

    Arrrgh....can't get any output ....Actually it is a very old beamer, which might be part of the problem.

    Quote from smp

    Try to increase the config_hdmi_b o o s t parameter in config.txt (the word b o o s t is censored on this forum for some reason, so no spaces)

    Increasing the value didn't work for me....still no output.

    Quote from Da Flex

    It is working without any option changes on LibreELEC. I have been tested it with Raspberry Pi 3B+, a HDMI cable and a HDMI to DVI adapter on a PC monitor. Make sure to first connect the display device, and then power on the Raspberry Pi. LibreELEC figures out, what display is connected, while booting.

    PS: It could be a PSU issue, too. The 3B+ needs more wattage compared to the 3B.

    I already many different variants but that didn't solve the issue. I bought myself a new rpi adapter with 2.5 wattage, which should fit quite well.

    Interestingly the older rpi3 worked fine out of the box with the same setup...some more suggestions, what I could do? Thanks for advise!!!

    Edit:

    I tried a different cable (vga) with a hdmi to vga adapter. And now it becomes strange, because this setting normally works everywhere i have been so far. But still the same problem...

    Maybe i give some more information about my setup:

    RPI 3 Model B+

    Hifiberry dacplus
    RPI Powersupply (2.5)

    To the RPi connected:

    USB Hub (with its own Powersupply)

    LAN Cable

    Cinch to the Hifiberry

    ...

    Edited once, last by benjamin10 (October 6, 2018 at 11:36 AM).

    • Official Post
    Quote from benjamin10

    Interestingly the older rpi3 worked fine out of the box with the same setup...some more suggestions, what I could do? Thanks for advise!!!

    Edit:

    I tried a different cable (vga) with a hdmi to vga adapter. And now it becomes strange, because this setting normally works everywhere i have been so far. But still the same problem...

    I think those points are indications for a PSU issue. Please try your older 3B with the LibreELEC MIcroSD card that you have in your 3B+ now. If it works with the 3B, you can be sure that the wattage of your PSU is the problem.

    I guess you are right. I tried a new installation of libreelec, but still the hdmi is not working. Everything else seems to work correctly (green light and red light is flashing) Is there anything I can do about the hdmi output? Could it be that it is somehow damaged?

    ssh into libreelec and then run tvservice -s and post the output.

    I'm using a HDMI-DVI cable on my test setup without issues and the tvservice output here looks like this:

    Code
    state 0x120006 [DVI DMT (36) RGB full 5:4], 1280x1024 @ 75.00Hz, progressive

    You should get a similar line, with "DVI" and "DMT" in there. If the HDMI cable is disconnected the RPi will switch to analog (CVBS) video output and you get a line like this:

    Code
    state 0x40001 [NTSC 4:3], 720x480 @ 60.00Hz, interlaced

    Note the "NTSC" in there, this means analog output is used.

    If auto configuration via DDC/EDID doesn't work you might need to manually set the video mode, using hdmi_group and hdmi_mode parameters in config.txt - see the RPi config.txt docs for details: Video options in config.txt - Raspberry Pi Documentation

    so long,

    Hias

    Add "ssh" to the end of /flash/cmdline.txt, after "quiet". Note that everything has to be in a single line and that there has to be a blank between "quiet" and "ssh".

    You can also edit this on your PC, cmdline.txt is in the first (FAT) partition of the SD card. If you do this make sure the file is saved with unix lineendings, so eg use Notepad++ on Windows.

    Or connect the RPi to some HDMI monitor and perform initial configuration there before switching to the problematic DVI cable setup.

    so long,

    Hias

    Thx for help...

    I got the follwing output:

    with hdmi_force_hotplug=1

    Code
    state 0x12000a [HDMI DMT (4) RGB full 4:3], 640x480 @ 60.00Hz, progressive

    And without hdmi_force_hotplug=1

    Code
    state 0x40001 [NTSC 4:3], 720x480 @ 60.00Hz, interlaced

    Beamer was switched on and connect prior to boot.

    ...i don'think it is an cable issue. I tried it with different cables working with other computers...

    Intresting is that i tried it with the follwing configs:

    Code
    # Force HDMI even if unplugged or powered off
#hdmi_force_hotplug=1
hdmi_group=2
hdmi_mode=9
hdmi_drive=1

    and uncommented

    Code
    # Force HDMI even if unplugged or powered off
hdmi_force_hotplug=1
hdmi_group=2
hdmi_mode=9
hdmi_drive=1

    Both is leading to the exact same output of tvservice -s

    Code
    state 0x40001 [NTSC 4:3], 720x480 @ 60.00Hz, interlaced

    ...The configs don't seem to work ....

    • Official Post
    Quote from benjamin10
    Code
    state 0x40001 [NTSC 4:3], 720x480 @ 60.00Hz, interlaced

    ...The configs don't seem to work ....

    Are you sure your beamer can deal with interlaced signals? If you still have the handbook, investigate what display modes are supported by the beamer. Here is my guisettings.xml, which uses 720p / 60Hz as default. You can try those settings on your device.

    Check out the whitelist on your guisettings.xml:

    Code
    <setting id="videoscreen.whitelist">.....</setting>

    Maybe the detection of available screen modes doesn't works right with your beamer. Detected screen modes will appear on that whitelist. Manually editing the whitelist (or using my guisettings.xml) could be worth a test, too.

    ....hmm i guess that is not really the problem. Thing is that i already tried different screens and the first installation on my samsung monitor worked. First install i had a signal but now not even this screens works anymore.... Can i check somehow if the graphics or the hdmi port is still working correctly?

    Shouldn't the output of tvservice -s different after changing the config.txt file?