Re: X50v ROM dumping + Flashing via SD Card

A few of us over at aximsite.com have found a method of dumping the ROM on a
Dell Axim X50v Pocket PC and then reflashing it via an SD card. This will
allow users with 'bricked' out of warranty Axims a chance to reflash their
devices when they are unable to use activesync. It also hopefully
contributes to the linux project.

The main stumbling block at the moment is that we need a working CRC file
but cant find out from Dell which CRC algorithm they're using. We're hoping
with a bit of luck that they're using one of the common implementations.

In a nutshell we have a file that refuses to be written to ROM without a
valid accompanying .CRC file and wonder if you know what format Dell use for
the .CRC file? An alternative approach would be to find the bootloader code
and reverse engineer/decompile it to see how it parses the required .CRC
file.

Best Regards
Paul Hanlon

---------------------------

Here's a little more background information :-

Dell have provided a method but not the necessary files :-
--------------
Follow these steps to install

1. Copy the image file (*.nb0) and the corresponding CRC file to one SD card
root directory (the SD card must be formated as FAT32).
2. Insert that SD card into PDA
3. Hold "Power" + "Wireless" + "Reset" simultaneously for one second.
Release "Reset" and hold the other two buttons until system comes up a
screen for SD Update Mode.
4. Use the navigator (Up or Down) to select which image you want to update
if more than one valid image existing on the SD card
5. Wait till reflash completes.

Note: If the card cannot be recognized, or no file is found, please
re-format the SD card and repeat the above steps.
--------------
Dumping the ROM

We've had a good bash at recreating a suitable diag.nb0 by dumping the ROM
using grab_it_128.exe from
http://forum.xda-developers.com/viewtopic.php?t=22861 but the bootloader
flash app on the Axim just sits there doing nothing with it. I think we need
to create a suitable .CRC file.

*Note* before dumping the ROM, the SD card needs to be renamed "Storage
Card"
1. Goto this registry Section [HKEY_LOCAL_MACHINE\System\
StorageManager\Profiles\SDMemory]
2. Change the *Value* of "Folder" to "Storage Card"

Not knowing which CRC algorithm Dell favour I created a CRC32 plaintext file
like :-

-----
CRC Values for diag.nb0

diag.nb0 -- 1293EAB9
------

...and named this diag.crc but this doesn't appear to be the correct format.

I understand that some crc standards also incorporate the file length which
is 62,601,657 bytes.

The discussion at aximsite can be found here :-
http://www.aximsite.com/boards/showthread.php?t=105233&page=3
Received on Tue Nov 29 2005 - 04:53:46 EST