Pinebook Pro refuses to boot from eMMC

[tophneal]

Thanks a lot for your time, effort, and patience with myself, being a complete noob.

You're not rude at all; I should have been clear: I don't know Linux much, and even though I've now read up a lot about U-boot.

Firstly, the bind/mount commands didn't mount anything. I performed an lsdsk, which actually listed the eMMC, but still.

Secondly, I ran Mr. Fixit's script as sudo:



Reboot did nothing: eMMC switch was in the correct position (towards the hinge) so eMMC wasn't turned off. I couldn't boot Pinebook Pro from the eMMC, but it could boot from SD.

Thirdly, I retried the script:



That did nothing either; the same result as mentioned at my second attempt (as mentioned in this post).

Fourthly, I did this:



After that little manoeuvre, the computer won't start at all, not from SD nor eMMC. I'm guessing I've now either completely bricked the computer or something else is the matter. At any rate, this computer is becoming my Joker's Origin Story, but I could have myself to blame completely, which I naturally accept. Desperation has brought me to this moment. 

Any help at this point would greatly be appreciated.

You're on the right path in that last image.

judging from the lsblk output, the emmc was bound and mountable. I goofed there. Binding will make it visible to the PBP again, so it can be mounted, but you don't necessarily need it mounted for this.

Concerning the dd commands you ran:
1. it'll need to be run with sudo.
2. do NOT include any partitions. you used mmcblk1p1, but you should be using mmcblk1. Look at the commands given on the page for pcm720's uboot that i linked previously.
3. don't bother with the SPI img. get rid of it, it's considered unstable even for those that know what they're doing, and it won't work on the emmc (it's made specifically for the PBP's SPI.) you write that to the wrong place, and you'll likely need to rewrite your emmc.

If your Debian SD won't boot, I'd just rewrite it. Easiest/fastest way to get it back up and booting.