I have spent today tinkering.
Background (as a level set):
- I chose update via webgui. Resulted in bootloop of eMMC (revealed when plugged into HDMI).
- Trying to boot from a fresh image on the microSD, with the eMMC still attached meant I kept crashing into an invalid root device error, which spat me to a shell. Ugh.
- I had to remove the eMMC card, and install a fresh image of dietpi on the microSD (took some time – multiple reboots / updates – be patient).
- Once dietpi was updated and running on the SD card, I then reattached (turn the power off first) and reflashed the eMMC using the instructions posted above (note the “wget” command is helpful to download the diet image directly on to Sparky microSD so that you can then flash it. You could also use a USB stick and mount it).
- When the dd copy is complete, then poweroff, remove microSD, and allow the image on the eMMC to bring itself up to date.
- If you have the eMMC adapter, get the screwdriver out, pull off the eMMC, and flash it directly. Quicker.
- If not, the above steps may be helpful