NO HDMI

Discussion in 'UDOO BOLT' started by Chris Taylor, Sep 26, 2019.

  1. Chris Taylor

    Chris Taylor UDOOer

    Joined:
    Sep 19, 2019
    Messages:
    3
    Likes Received:
    0
    Hi I'm wondering if anyone can help no HDMI signal absolutely nothing, Ram is to spec, HD compatible tried various monitors even my TV.

    Rgds
    Chris
     
  2. nophead

    nophead UDOOer

    Joined:
    Aug 18, 2015
    Messages:
    62
    Likes Received:
    4
    I had to use an UDOO HDMI cable and my TV to see the BIOS. For some reason the ports are very picky as the first HDMI cable I used works with all my other SBC's, of which I have many, and so do my ASUS monitors.

    I actually put a Ubuntu live image on a USB key and discovered it booted and appeared on my network before I got the HDMI port to show anything. I thought the board was dead.
     
  3. ccs_hello

    ccs_hello UDOOer

    Joined:
    Apr 15, 2017
    Messages:
    391
    Likes Received:
    150
    Sometimes, it is the proper HDMI cable that determines if there is display or not.
     
  4. nophead

    nophead UDOOer

    Joined:
    Aug 18, 2015
    Messages:
    62
    Likes Received:
    4
    Define proper? All my devices except UDOO Bolt work with any HDMI cable and any monitor. There is something wrong with the UDOO bolt HDMI implementation and something wrong with the BIOS firmware as even with a cable and monitor that works in Ubuntu it doesn't show the BIOS, which is a complete pain for me because I have to disconnect three perfectly good monitors in my lab and take my bolt on a trip to my TV in the lounge which has overscan.
     
    Chris Taylor likes this.
  5. Chris Taylor

    Chris Taylor UDOOer

    Joined:
    Sep 19, 2019
    Messages:
    3
    Likes Received:
    0
    I totally agree all my devices work with any HDMI cable and any monitor apart from the UDOO BOLT!
     
  6. ccs_hello

    ccs_hello UDOOer

    Joined:
    Apr 15, 2017
    Messages:
    391
    Likes Received:
    150
    HDMI 1.1, 1.4, 1.4a, and 2.0 have slightly different spec.
    so likely UEFI firmware needs to see different signals than what an OS (with proper diver loaded) can offer.

    Note: HDMI full spec has 19 leads defined, other than transmitting the video signals and timing, it has the option to carry CDC, HDC, and/or I2C
    (DCC) signals all well. So does cable allow the proper signal to pass-thru, does the HDMI monitor have the successful monitor capability/DRM negotiation, etc. can all play part in.
     
  7. nophead

    nophead UDOOer

    Joined:
    Aug 18, 2015
    Messages:
    62
    Likes Received:
    4
    Yes but all the HDMI specs are supposed to be backward compatible and I don't think the BIOS needs to care about DRM or put out a 4K signal, etc. All the BIOS needs to do is what my other older PC BIOSes do.
     
  8. ccs_hello

    ccs_hello UDOOer

    Joined:
    Apr 15, 2017
    Messages:
    391
    Likes Received:
    150
    I wish everyday is a sunny day.
    re: "backward compatibility", oh yeah, that's why my basement is full of old junk electronics.
     

Share This Page