Problem: The Micro SD card completely died, shows up as some 32MB unit, unformattable and only drops zeroes when dumped. It seems impossible to restore the LaMetric Time to any working condition without a new SD card, with the correct MBR/GPT and bootloader.
The firmware update files provided only contain a squash of the rootfs for update or restore, when the SD, Bootloader and Recovery image are still working.
I have already tried around 10 precompiled bootloaders (u-boot with spl) for some other Allwinner A13 based boards, but the serial dump always dies with errors, likely due to wrong hardware parameters compiled into these bootloaders (mostly mmc init failed).
There's a few simple solutions, to that actually.
One would either need a complete burnable .img for a new micro SD card (including all the firmware),
or a dd writable .bin file that contains the correct MBR, GPT and bootloader for the card.
It would be greatly appreciated if someone with a working unit could dump their bootloader bin of their SD card, it would also help future users whose SD card dies.
Feel free to contact me should you have any questions on how to dump the MBR+GPT+Bootloader part.