Steps for Installing Alternative OSes in 2022

[jazzhands]

I have a 2022 Pinebook Pro. I used dd to write an OS image to an SD card, in my case NetBSD which I sourced from here:

http://nycdn.netbsd.org/pub/arm/netbsd-9/

Last time I ran NetBSD was years ago, on a different architecture. When I reboot the power led blinks and then nothing happens. Maybe I'm missing something obvious.

After searching I found this post:

https://forum.pine64.org/showthread.php?...#pid113987

To wit:

The version of Manjaru that comes pre-installed on the 2022 Pinebooks Pro, includes a U-boot that does not allow booting from micro-SD card.

The ways to resolve this are
1) replace the U-boot on the eMMC with a different one, or possibly Tow-boot
2) wipe out the eMMC and install a different operating system on it.
3) install Tow-boot to SPI ROM (I do not actually recommend this, but it can be done, apparently).
4) disable the eMMC 

OK, so I need to do one of 4 things which I have no background to assess the relative merits thereof. Maybe I want to do the easiest one.

For #1, I can't find anything that looks apropriate and recent.

For #2 I'm not sure I want to get rid of Manjaro yet.

Why would #3, installing Tow Boot to SPI be a bad choice? Anyways, I found these tutorials for that:

- https://tow-boot.org/devices/pine64-pinebookPro.html
- https://forum.pine64.org/showthread.php?tid=17529


#4 is not appropriate obviously (can't boot from SD)

Any pointers and thoughts would be appreciated.