3 days in, slow/stuck or no boot.

[lgmpbp2]

@KC9UDX @wdt
Thank you for the responses.
With some trepidation, I zero'ed the SPI. Unfortunately, I cannot boot anything, now, although yes, at one point, I could boot pmOS from SD card with emmc turned off. Then, I pressed reset and recover. Now, I cannot put tow boot spi.installer.img on it, again, or anything, at all.
When using fcsk or lsblk, all that displayed was the sd card or usb stick, not the emmc. The emmc wasn't recognised. Therefore, when I tried to install pmOS when booted into pmOS, it just saved the install to the usb stick.
This becomes frustrating & disheartening.
If anyone has any suggestions to get this PBP up and going, then yes, I am open to them.

[wdt]

BUT, but when you got the pbp, it was booting from the emmc,
so it must have been recognized then (that particular emmc at least)
The "emmc turn-off" button is a bit flaky, try to boot from sd with emmc removed
I don't know what kind of emmc adapter you have, some are usb and some are sd
If it is usb, and if pmOS boots from sd, then use that to flash armbian on working emmc
(the emmc that had manjaro on it, in adapter, plugged into usb, or a fsck alternatively)
OR, maybe the emmc socket has been damaged, this is a possibility
One other thing to try, if it appears completely dead is a "hard reset" hold pwr button down for 20+ seconds
OR, sometimes a "hard power-off" is useful, hold pwr button down for 8 seconds (usually try this 1st)
----
Please be really careful to use ONLY images for "pinebookpro" and NOT "pinebook"
They are completely different CPU and u-boot locations, you WILL need to do a hard reset after
an attempted boot with allwinner uboot boot attempt

[lgmpbp2]

Thank you for responses. Pinebook pro booted from emmc to start with for approx. 3 days, after I got it just over 2 months ago. After a Manjaro update, it then went to black screen and didn't boot at all. Then, put Tow-boot onto PBB and managed to boot into pmOS, but couldn't get it onto emmc. Received messages to the effect that card or emmc not recognised voltage select -110. After awhile, could only use USB sticks with pmOS, not SD cards. Unfortunately, zero'ed SPI flash which caused an inability to boot at all- black screen, only light is at red barrel port charging. Pressed power off 7-8 seconds (several times) as suggested. Unplugged battery and barrel charger several times to see if red power light would come on. Tried Tow-Boot, pmOS emmc (emmc area doesn't appear damaged), pmOS sd cards( yes, I have PBP images).Nothing works. It seems that PBP is e-waste, now. This is quite disheartening as I wanted to use it for some work as well as to learn more about such laptops and Linux in general.

[wdt]

Probably the voltage select problem is from pmOS, that's a guess, if I was betting, that's where I would put money
You have a emmc adapter, is it usb or sd? If sd, do you have a card reader?
The reason manjaro does not boot is likely that the emmc (one of the partitions) needs a fsck (do both)
(the other problem is manjaro's uboot is still defective months later, has problems booting sd, this is a long standing problem)
I assume you have another computer, probably a windows box?
Do you know how/are capable of making this (other computer) do a "linux live boot"?
Try an armbian image on a sd card
----
Ordinarily the pbp cannot boot from usb, that you could was because you had tow-boot on SPI
The boot loader in the cpu is really limited, only searches SPI, emmc, sd (in that order) to find idbloader,
which initializes memory and then has enough (mem) to load uboot, uboot then alters boot search order
Likely, when you wiped SPI, the next idbloader (and uboot) is on emmc, manjaros uboot which has problems booting sd
And that is likely why you get no boot, I bet if you try to boot with the emmc removed, everything would just work
If my guess is right, then reinstall towboot to SPI

[KC9UDX]

Whatever happens, do not give up hope. I might be wrong but I seriously suspect that every serious PBP user has been through exactly what you're experiencing.

[lgmpbp2]

Whatever happens, do not give up hope.  I might be wrong but I seriously suspect that every serious PBP user has been through exactly what you're experiencing.

Thank you for the supportive responses, @wdt and @KC9UDX 
1. I've used Linux for approx 5 years on Windows or former Windows laptops. With respect to PBP, I flashed images for PBP on Windows on this older Lenovo Thinkpad and then I changed over to Debian. Used Etcher on both and Disks on Debian. Am not necessarily a Linux newbie, but am not a techie, either. Am not entirely sure that I flashed some software images well- that is, archiving, extracting etc. so that I will go over the Getting Started version of Pine64, again. https://pine64.org/documentation/Introdu...g_started/

2. I use Pine 64 store's USB adapter for emmc module and it seems to work well https://pine64.com/product/usb-adapter-for-emmc-module/ I  put pmOS on a new emmc module and put Armbian on the older emmc module and then changed and put pmOS on it because pmOS was the only OS/distro that seemed to work.

3. I use Sandisk Mobilemate+ reader and IOgear reader, usually in USB 2 port. Also, I use either Sandisk 32 G A1 sd card, Lexar 64 g or Kingston 32. Tow-boot is on a Transcend 8G card. For USB sticks, I found that Kingston or Sandisk worked.

4. I left the PBP battery unplugged overnight  and pressed recovery, power off for about a minute each, after trying Tow-boot, sd cards with pmOS. As well, I tried a few suggestions from this 2 year old thread specifically ayufan's uboot erase and uboot flash. Nothing worked. https://www.reddit.com/r/PINE64official/...r_good_or/  https://github.com/ayufan-rock64/linux-m...t/releases
Yes, I tried sds with emmc removed or turned off--- is turning it on really turning it off. I read somewhere on here that it is this way?-
Nothing worked and it is very disheartening. The red power light at the barrel port is on when plugged in with charger.
This is a lovely laptop and I wanted to use it with either Abiword or Libre Office, to watch videos (yes, I did so already and the display or screen is nice); listen to music on Elisa and some more and learn a bit more about Linux and such laptops.
Although I am aware it is nearly impossible to totally brick PBP, I am not sure what else to do. Thanks again.

[wdt]

Yes the emmc switch, on is.... disable= on = emmc off ,, This is indeed backwards to normal understanding
occasionally the sd sodket or board is bad, at a guess 1 per 10K
Is it possible that the SPI did not get completely erased?
Maybe I misunderstand, I thought you said the voltage select problem was for emmc
with a pmOS usb boot, but now you say pmOS worked on emmc?
To erase uboot, just write /dev/zero to 1st 16M, maybe save mbr first if it would be usefull, as so
dd if=/dev/zero of=/dev/something bs=1M count=16 ..... all this as root,,,, to install image (most are .xz)
xzcat image |dd of=/dev/something bs=1M ....but VERY sure that you have right output file, of=
SPI is different, idbloader starts at 0 rather than 64 sectors as on sd, emmc

[lgmpbp2]

Yes the emmc switch, on is....  disable= on = emmc off ,, This is indeed backwards to normal understanding
occasionally the sd sodket or board is bad, at a guess 1 per 10K
Is it possible that the SPI did not get completely erased?
Maybe I misunderstand, I thought you said the voltage select problem was for emmc
with a pmOS usb boot, but now you say pmOS worked on emmc?
To erase uboot, just write /dev/zero to 1st 16M, maybe save mbr first if it would be usefull, as so
dd if=/dev/zero of=/dev/something bs=1M count=16    ..... all this as root,,,, to install image (most are .xz)
xzcat image |dd of=/dev/something bs=1M    ....but VERY sure that you have right output file, of=
SPI is different, idbloader starts at 0 rather than 64 sectors as on sd, emmc

Thanks for the response, @wdt 
Thanks for clarification of the backwards emmc switch's on and off. That is helpful.
Voltage select message seemed to occur with not only pmOS but also Armbian as I recall. Nothing would really boot up and would receive the voltage select message.On Tow-boot, voltage select message occurred with emmc, sd, usb. pmOS would boot up from usb, eventually, but it would boot up without going through Tow-boot or that is how it seemed to work.
To be clear,the usb emmc module adapter seemed to flash the pmOS software well enough on my other laptop. But emmc modules don't seem to work on PBP.
Thank you for the erase u-boot formula. I believe this has been a u-boot problem, or at least most of it, and perhaps the timing is off somewhere. I don't know if SPI flash is completely erased but it certainly seems that way since I cannot even  put Tow-boot on, again.
Would it be possible for someone to put the solution to the Manjaro u-boot issue on here somewhere?
I really don't know what else to do. It has been said that totally bricking the PBP isn't possible and I hope so and hope that I could eventually get this going, somehow. Thanks again.

[KC9UDX]

You can get a different U-Boot. The one that comes with NetBSD works well. I'm not sure how to point you to the correct procedure at the moment, but you need to put U-Boot in the right place for it to work. I'd like to say that Tow-Boot might help you but I just have no experience with it.

[wdt]

>I don't know if SPI flash is completely erased but it certainly seems that way since I cannot even put Tow-boot on, again.
Well, you have to get a boot to be able to write anything
One thing, somewhat advanced, make a plug and flip switch to get serial output (from audio socket)
I have serial from nearly all of my SBC, but not pbp, have not ever opened back, have not made jack
Every image has idbloader and uboot in 1st 16M, also mbr in 1st sector (unless gpt, that is 34 sectors),,, so..
save mbr.... dd if=/dev/something of=emmc.mbr count=1 (dd defaults to bs=512..(bytes))
a still compressed image ... xzcat image |dd of=1st-16M.distro bs=1M count=16
Then using dd write 1st-16M.distro to whatever target, them mbr to overwrite probably wrong mbr
You don't need count, dd will stop when if reaches end of file, but for larger writes to flash bs=1M is MUCH better

Two other things
Under a strong light and a strong magnifying glass, look at emmc pins and socket, for bent pins
There is a (sometimes flaky) button to disable SPI, push, wiggle and hold just before powering on (for 3-5 sec)
(with something bootable in sd and emmc turned off/removed)
It doesn't always work (the button) If it does boot, wipe the SPI again

Oh, last point. If you actualy had tow-boot on SPI, that was what was booting anything, pmOS or other
since SPI is first in the cpu boot order and the 1st idbloader/uboot found is what will be used

Again, when uboot loads it changes boot order, uboot is looking for
boot.scr OR extlinux.conf in 2 specific places (since uboot does not know if it is a 1 or 2 partition setup)
ie boot.scr or boot/boot.scr (some, *BSD I think, use aarch64.efi, this is less common)
Then uboot reads that config file and knows what and where to boot