Back up of the "Factory Bad Block Table" BBT, needed or a waste of time?

Visti Andresen talpa at
Sat Jul 28 14:46:24 CEST 2007

I'm probably going to receive my Neo next Monday (the joy).

Therefor I'm curious about backing up important data from the device before
I start to playing around with it.
As far as I can tell there are to bits of important data?

The gpsd 
The "Factory-programmed NAND bad block information"

The gpsd should be backed up by the procedure in:

However badblock information is stored in out-of-band (OOB) data

and inside the bad block table (BBT), I guess that the BBT isn't located 
inside the 4. partition and therefor not backed up?

Is it necessary to back up the BBT alt all?

Can the "factory BBT" be recreated using JTAG?
or has the factory used a special kind of "magic" when
establishing the BBT?

The recreation may of course not be an exact copy of the original as some
FLASH pages may have gone bad since then.
But that shouldn't be a problem....

If the JTAG recreation of the BBT is actually a working "Factory BBT"
I suppose it isn't necessary to back it up, as any error sever enough 
to cause the need for a restore of the BBT probably will require 
a JTAG reprogramming anyway.

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