Hi,

I was tempted to upload a new image from debian from http://seafile.servator.de/nas/zyxel/images/
after uploading to the SD card debian-nas-bullseye-21.214-armhf.img.gz the system started correctly.
In the next step I did a kernel upgrade to linux-image-3.2.102-1-nas5xx-armhf.zip and unfortunately it did not work properly.
As recommended before rebooting, I ran the rollback routine sudo / firmware / sbin / info_setenv next_bootfrom 1
Errors have occurred and the NAS has restarted.

He has fallen into a noose since then and I cannot save him.
I tried:
- universal_usb_key_func-2015-10-12
- NAS540_521AATB3C0_Upgradekey
- I connected the serial port but the kosola only shows "bushes" and the NAS restarts.

I am asking you for help and suggestions.

manticore

manticore,

I don't have this device, or any FreeScale CPU box, so cannot help you. Hope other who has this device can help.

-bodhi
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Tanks bohdi,

So informative:

Hurray,
However, I changed the USB / TTL from PL2303 to CP2102 and it's beautiful. (Console works)
The logs show that it cannot load:

Hit any key to stop autoboot: 0
booting kernel of type uimage from /dev/nand0.kernel2.bb
Verifying Checksum ... Bad Data CRC
Failed.
booting kernel of type uimage from /dev/nand0.kernel1.bb
ERROR: out of memory

I have both kernels damaged.

Now I'm thinking What next?

manticore,

The boot log indicate that this is barebox bootloader (not u-boot). I don't know barebox, only have done some reading in the past. barebox is a fork of u-boot, the inner working is similar, but the user interface is different.

booting kernel of type uimage from /dev/nand0.kernel2.bb 
booting kernel of type uimage from /dev/nand0.kernel1.bb

I can only suggest: find a good image for the kernel and boot with tftp.

As the exact syntax how to do that, you need to find out from some barebox forum somewhere.

-bodhi
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Hi,

I break loop from the console and type bootm -n.
I was able to start debian by booting the kernel from the console with the parameter -n "bootm -n /dev/nand0.kernel1.bb"

I turned it into an env:
# boot partition
next_bootfrom = "2"
curr_bootfrom = "1"
and everything worked fine.

Then I did a trick and made a kernel update from the previously working system on the SD card.
Thanks to this, I now have two working kernels in NAND. (nand0.kernel1 and nand0.kernel2).
Currently I have curr_bootfrom = "2".

Little note: "Most even professional devices have duplicate boot systems. In our case, there are two kernels and rootfs in different memory areas. This is a security measure, if the modification did not work, you can roll back, as long as you don't panic and do it correctly. "

Maybe someone will find it useful to know:

In NAS540-542, after connecting the console via RS232 / TTL and turning on the power, we will see the bootloader start.
We can stop it "Hit any key to stop autoboot: 3 sec"
And see or edit env config with edit /env/config (we exit with CTRL + D)

Thank you Bodhi for Your support