My problem is specific to the Tomtom device: by replacing the original
'ttsystem' file from the internal memory by my own (with my kernel, my
filesystem, packed together with the image building tools from the
Wiki), will I be able to restore back the original version if
something
goes wrong ?
I was worried about that with my 910, too. I originally even went
that far that I checked that the internal hard disk was connected
through an IDE connector so that I could have connected it to an
external USB box or something.
However, it turned out that at least 910 boots to USB disk mode if
connected to a USB host during the boot. That is, even without a
working ttsystem, if I reset the device, put it to the USB dock, and
power it up, the firmware puts it directly to the USB target disk
mode, allowing me to access the internal hard disk contents.
I suppose 920 would work the same way, but perhaps you should test...
--Pekka
