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Subject: Data CRC failed on node...
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Hi All,

    I have a 5272 Motorola Coldfire based board, running "uClinux dist. :
uClinux-20030305.tar.gz" +

"Tool Chain : m68k-elf-tools-20030314.sh.".

I have a 2Mb flash (AMD AM29LV160DB) using MTD + JFFS2.

It has worked fine for a long time, then I received the following message
during the bootstarp :

        Command: mkdir /var/run
        Command: mkdir /var/lock
        Command: mount -t jffs2 /dev/mtdblock2 /mnt
        jffs2_scan_inode_node(): Data CRC failed on node at 0x0005ca64: Read
0xb399e587c
        jffs2_scan_inode_node(): Data CRC failed on node at 0x000a1424: Read
0xee61d2b26
        Command: ifconfig lo 127.0.0.1
        Command: route add -net 127.0.0.0 netmask 255.0.0.0 lo

To fix the problem I do the command "eraseall /dev/mtd2" and the error was
cleared.

I have posted the problem to the uClinux List and I received the following
answer :

>>        Yes. Pls umount when u done using the flash. Because if u don't
unmount
>>        properly it will just scan for the nodes once again when the
filesystems
>>        comes up next time. It's just scans all the nodes,if u properly
unmount
>>        the filesystem before turning it off. So pls ensure u umount the
>>        filesystem before turning off.


Do I have to mount/unmount the flash every time I have to read/write from it
?

Which is the correct way to read/write from flash to avoid the "Data CRC"
problem ?

Thanks!

Massimo.