Announcement

Collapse
No announcement yet.

4DPi-35-II Kernel - Raspberry 3 USB Boot Mode

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • 4DPi-35-II Kernel - Raspberry 3 USB Boot Mode

    Hy,

    i´m using an Raspberry 3 with the jessie lite linux and with the 4DPi-35-II display.
    The display works fine when i use the sd card as memory.

    Now i have to boot my raspberry from USB. This works fine with this tutorial:
    https://www.raspberrypi.org/document...otmodes/msd.md
    During this installation the kernel changes and because the display uses the kernel7_hat the usb boot doesn´t work.

    Is there a tutorial how i can install the display software manually?

    Thanks

  • #2
    Hi,

    it is always possible to compile a custom kernel; but does kernel7_hat.img kernel not work if installed on USB drive? I have browsed the tutorial and it looks that the point is in upgrading bootcode.bin, start.elf and changing OTP. So likely the _hat kernel should still work (but haven't tested...). Once your RPi is booting from USB, I'd just try installing the 4DPi kernel package (but make a backup first...)

    Comment


    • ggRasp
      ggRasp commented
      Editing a comment
      Hi,

      i have already tried to install the 4DP kernel after the USB boot installation.
      I only get a colored screen at startup and nothing more happens. When i delete the kernel7_hat entry in the /boot/config.txt the system will boot from USB again. but in this case the display will not work.

  • #3
    Hi, colored screen and nothing else usually means that the kernel can't be loaded, so I am not sure whether start.elf can find the _hat kernel; you can try removing the kernel= line from config.txt and renaming kernel7_hat.img to kernel.img. It is also possible that _hat kenrel is not compatible with new firmware that was installed with upgrading. If this is the case it will be necessary to get the new kernel's sources (probably using rpi-source), and compile a custom kernel.

    Comment


    • ggRasp
      ggRasp commented
      Editing a comment
      Hi,
      renaming the kernel doesn´t work, i have already tried it. how does it work to compile a new custom kernel with our drivers? i´m not really a linux expert.

  • #4
    There is a good tutorial for building the kernel here: https://www.raspberrypi.org/document...l/building.md; basically the procedure would be:
    -build the kernel directly on RPi running from USB; get kernel sources with rpi-source (https://github.com/notro/rpi-source/wiki)
    -follow the tutorial (on RPi3 build takes about 90 minutes)
    test the kernel that has been build
    -follow the readme file: https://bitbucket.org/4DPi/4d-hats, and rebuild the kernel again (it will be much faster this time...)
    good luck

    Comment


    • ggRasp
      ggRasp commented
      Editing a comment
      Hy,
      i think i was able to build a new kernel!
      the rasp boots from USB and the display shows something. but i´m missing the login message. i only can see it on the hdmi output.
      Do you have any idea where i can find this setting?
      Thanks.

  • #5
    Dear ggRasp,

    The best way to do it is to use an Raspbian image in which you have already applied the 4D Hats
    package.

    1. Using the win32diskimager, make an image of the modified Raspbian image to your USB flash drive
    2. Format your uSD card with FAT and copy the contents of the USB flash drive.
    3. In your PC modify the config.txt and choose the model of your 4D PI display.
    4. In your PC also change cmdline.txt on sdcard from root=/dev/mmcblk0p2 to root=/dev/sda2
    5. Insert uSD card to Raspberry Pi and also your USB flash drive.
    6. Power up.

    Best regards,

    Comment


    • #6
      Hi, for console, try this command (execute it through ssh or in HDMI console...):

      con2fbmap 1 1

      this command is executed at boot time from /etc/rc.local file (from 4dpi kernel package)

      Comment


      • ggRasp
        ggRasp commented
        Editing a comment
        no this command didn´t solve the problem. maybe there is any to edit in the /boot/config.txt?

    • #7
      Dear ggRasp,

      Edit the /boot/config.txt using this command:

      sudo nano /boot/config.txt

      uncomment or remove the # to this --> dtoverlay=4dpi-35

      press ctrl x and Yes then sudo reboot

      Best regards

      Comment

      Working...
      X