>How/where do I save data?

From userland, for most apps, you'll have to use the disks.
They'll spin up if you read from them (I hope, if not we'll fix that).
But yes, they're normally R/O, so you'll need to fix that also.

Global machine settings (eg. voladj, screen blanking, etc..) are better suited to storage in the Flash memory reserved (or stolen ) for such stuff. But this is a very limited resource.

I suppose somebody will need to write a small app to load/save data from a reserved disk sector or something, which could be done without much trouble and which would avoid having to remount the fs rw . Or maybe just bite the bullet and do the rw remount, save data, and then mount ro again.

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