Happy eMMC and SDcard OS usage for Pinebook Pro Newbies...

[Mangled]

OK, lsblk 1st,, boot0 and boot1 are on emmc, I will use terms /dev/SD and /dev/emmc,,
replace SD and emmc with right mmcblkX
Then, sudo gdisk /dev/SD,,, the screen that comes up will have this section

Partition table scan:
  MBR: MBR only
  BSD: not present
  APM: not present
  GPT: not present

So you can tell the partitioning style of the disk, Ayufan often uses GPT
If it is mbr, you save 1 sector, if gpt save 34 sectors,,, (dd default bs is 512 Bytes, 1 sector)
(GPT has protective mbr, 1 sector, GPT boot code, 1 sector, partition table, 32 sectors,,4/sector,128 partitions)
make a directory to work in, empty
cd ; mkdir uboot-sav ; cd uboot-sav
save SD mbr
dd if=/dev/SD of=SD.ubuntu.mbr count=(either 1 OR 34)
save ubuntu uboot(optional), good practice to always be able to go back
dd if=/dev/SD of=ubuntu.uboot.16M bs=1M count=16
Transfer 1st-16M emmc->SD
dd if=/dev/emmc of=/dev/SD bs=1M count=16
restore mbr
dd if=SD.ubuntu.mbr of=/dev/SD  (count not necessary, will stop at end of file)
Also a good practice to give self documenting names, very helpful a month later
This assumes manjaro on emmc,, ayufan ubuntu on SD,, ubuntu boots OK
Doesn't matter where you boot from, but if SD card is in, will boot ubuntu
Then test, remove/disable emmc, can SD boot OK?  If so, transfer ubuntu to emmc,,
with rsync (already in forum OR on other computer OR do an install from image,, BUT
BEFORE rebooting transfer manjaro uboot to emmc (saving emmc mbr 1st, and restoring last)

Thank you so much. Yep the image had GPT partition. Followed your steps and it worked. I booted into Ubuntu 20.04. However I updated Ubuntu to 20.10 and it boots but fails and tells me to enter maintenance. I may have to attempt the steps again for the new update.

[wdt]

There are yet some more steps (in booting) AFTER uboot has found extlinux or boot.scr
Since uboot has a somewhat generic dtb (specific to a particular cpu family),
once it loads extlinux/boot.scr, it then reads what dtb is referenced, loads it for its own use
(because that dtb is specific for that device),, then finishes setup
The kernel loads, also loads dtb to know specifics of that hardware
And then the video drivers for X have to be right, most of the rest of the hardware is generic
In 20.10 can you get a vt? ,, I mean does it get booted that far?
--edit--
And you know, anything that has ubuntu in sources.list, well you can make sure there is a display manager (sddm?)
and go wild with synaptic/apt-get.. Sometimes there is a task-(window-manger) to make it simpler,
still have to fill it out but that does 1/2 (for example,, task-xfce)

[middlecope@gmail.com]

Download ChromiumOS (made by Ayufan) Placed it on USB stick with OpenSUSE imagewriter.
Started PBP with the USB stick attached. No booting on the stick I only see Manjaro.
Is there some trick to enter U-boot? I am only used to GRUB
Thanks for your attention.

[wdt]

>Is there some trick to enter U-boot?
Unless you have a serial connection, you will see nothing, well samueldr uboot shows on display
So, take off back, flip switch, plug in 3.3V converter, use some terminal emulator, I use putty
('cause you don,t have to remember command switches, others work OK)
Usually hit space to stop boot, then use uboot command line
BUT
the best way to test that Chromium image would be on SD, usb boot is a bit "spotty"

[middlecope@gmail.com]

>Is there some trick to enter U-boot?
Unless you have a serial connection, you will see nothing, well samueldr uboot shows on display
So, take off back, flip switch, plug in 3.3V converter, use some terminal emulator, I use putty
('cause you don,t have to remember command switches, others work OK)
Usually  hit space to stop boot, then use uboot command line
BUT
the  best way to test that Chromium image would be on SD, usb boot is a bit "spotty"

Thanks for the answer.
It is getting complicated. I have to buy an USB-serial connector. I am living on a small island in the Caribean.
Do I have to order the "EZSync USB to TTL(RS232) Cable, FTDI Chip, 3.3V TTL, 1.8 Meter, 3.5mm Audio Jack, TTL-232R-3V3-AJ (Transparent)"
That will add $ 50,- to make my PBP work.
By the way: Does anyone know: If I place ChromiumOS (Unfortunately I love Linux) Can I make Skype video calls in the Chrome browser?
All answer are appreciated. You are helping a retired programmer (Pascal language)
Thx, Teunis

[middlecope@gmail.com]

>Is there some trick to enter U-boot?

I also found "DSD TECH USB to 3.5mm 3.3V TTL Cable with Audio Jack Interface 6FT" on Amazon
It was reviewed favoureble by an amazon client, who used it for a PBP The price is $ 12,-

[wdt]

OR, if you can solder <$5,, tip,, DON'T buy FTDI from china or anywhere that gives no guaranty
lots of fakes, almost 100% from ebay, real FTDI are ~$15
Do get something that can be jumpered 3.3V

[middlecope@gmail.com]

I bought the "DSD TECH USB to 3.5mm 3.3V TTL Cable with Audio Jack Interface "
It will arrive in about 3 weeks. After that I can give it a try.
My soldering is no good because I only have one working eye.
When I countinue I will start a new thread "ChromiumOS on PBP" to tell about my experience.
Thanks WDT for your advices.
I don't understand the terminal emulation part. Maybe you can advice me on that in the new thread.
I use Putty to work on a server via SSH. I have to find out howto with PBP. For me it is a challange.
Thx, Teunis

[feoh]

What are you using to burn the SD card?

I've had two varieties of problem with trying other distros:

1) Burning SD cards incorrectly using Balena Etcher. I had better success with dd
2) Manjaro playing fast and loose with writing to the emmc even when booting off of SD

Also which Ubuntu image are you using?

[middlecope@gmail.com]

What are you using to burn the SD card?

My configuration is a PC with Linux OpenSUSE as OS.
I use the  SUSE Studio ImageWriter.
The written SD or DVD were adequate for me to load on a PC with x86-64 CPU
No experience until now with ARM CPU