repair advice for bad NAND blocks Options

[Zuber]

You did all this, and you did not ask them when the new version would be coming out and what the specs would be ?

How could you ?

[kitsnews]

If you're careful, you could try erasing the flash using Linux.  It could be a little complicated unless you're a Linux guru, but the basic idea would be to boot from the special ROM Linux (or alternately setup a ramdisk setup with the essential utilities), unmount all the flash filesystems, and run the flash_erase utility, which you can get in the mtdtools package I uploaded here recently.  Then go back and restore the flash.

p.s.  I make no guarentees this is really a good idea.  :)

Dear DrWowe,

GREAT!!! you guide me to explore another world of zaurus. I have searched in-depth working detail of zaurus for long. But I can't find any.

By the word mtdtools, I find this.
http://www.zaurususergroup.com/index.php?n...iewtopic&t=3986

Thanks a lot.

Actually, I am a so-called system engineer in linux/bsd field. But I don't know the working of zaurus at all.

Thanks a again.

[jchung]

Hi all,

I just recently bought a c760 from ebay with the same problem as the original poster.

The guy I bought the unit from couldnt get the c760 NAND to flash... any suggestions on what I should do?

the strange thing was he was able to flash the unit using a c860.dbk. I was able to access the OK + power menu but when I try to reset the device or flash a new ROM the screen just goes blank.

If i go into D + M menu it's white (c760) but if I go into P + D menu it's red (c860)

I tried reflashing using a c760 NAND but it gives me the error

[Stubear]

Hi all,

I just recently bought a c760 from ebay with the same problem as the original poster.

The guy I bought the unit from couldnt get the c760 NAND to flash... any suggestions on what I should do?

the strange thing was he was able to flash the unit using a c860.dbk. I was able to access the OK + power menu but when I try to reset the device or flash a new ROM the screen just goes blank.

If i go into D + M menu it's white (c760) but if I go into P + D menu it's red (c860)

I tried reflashing using a c760 NAND but it gives me the error

Because the unit was flashed with a C860 NAND it now thinks it is a C860, you will have to rename the C760 NAND to make the Z think it is a C860 NAND - change the "7" in the name to an "8" before you copy the NAND across.

That should do it (did for me anyway)

Stu

[jchung]

Hi all,

I just recently bought a c760 from ebay with the same problem as the original poster.

The guy I bought the unit from couldnt get the c760 NAND to flash... any suggestions on what I should do?

the strange thing was he was able to flash the unit using a c860.dbk. I was able to access the OK + power menu but when I try to reset the device or flash a new ROM the screen just goes blank.

If i go into D + M menu it's white (c760) but if I go into P + D menu it's red (c860)

I tried reflashing using a c760 NAND but it gives me the error

Because the unit was flashed with a C860 NAND it now thinks it is a C860, you will have to rename the C760 NAND to make the Z think it is a C860 NAND - change the "7" in the name to an "8" before you copy the NAND across.

That should do it (did for me anyway)

Stu

yeah I did do that, but it's still having problems.. So most likey the unit can only be used for spare parts..

These are the errors I get when trying to do stuff in teh D + M menu

NAND Flash (sum): "Can not read sum area"

(in extra menu) NAND Bad Count: "ERROR! cannot initial. code=(-2)"


in the P + D menu:

NAND Bad Count+Sum: "ERROR! cannot initial. code=(-2)"

NAND Flash Erase: "ERROR! cannot initial. code=(-2)"


what's strange was I was able to do bad count checks and usually it would come back with a few bad blocks.. and sometimes it would give me like 7000 something bad blocks..



I think there's no hope for this c760. maybe if someone would be kind enough to receive the zaurus after I send it to Sharp Japan for repair..

[mspencer]

My C700, which I just got back from Japan a few months ago, is having the same problem again. I had programs lock up intermittently, and now it won't boot. Same flashing lights.

It's not going back to Japan again -- I'll buy a C3000 from conics.net first. But maybe I can salvage this device.

--Michael Spencer

[speculatrix]

My C700, which I just got back from Japan a few months ago, is having the same problem again.  I had programs lock up intermittently, and now it won't boot.  Same flashing lights.

It's not going back to Japan again -- I'll buy a C3000 from conics.net first.  But maybe I can salvage this device.

--Michael Spencer

In my experience, from years gone by when I did embedded microprocessor systems, when you get a memory problem it isn't just the memory:
* bad memory cells in the device (individual memory locations faulty - stuck bits)
* bad memory interface in the memory device (whole row or column faulty, e.g. 256 bits stuck, or, always bit 0 of every location)
* a failed address or data bus driver on the CPU causing it to wrongly address chunks of memory (manifests same as bad memory interface in memory device)
* a PCB fault on the address or data bus (manifests same as bus driver and memory interface) - either a short to a neighbouring "wire" or a crack in the PCB causing open circuit.
* a bad connector or dry joint causing bus problem

Bad memory cells, bad memory or bus interfaces are usually permanent. PCB faults are more likely to be intermittent, and can go away depending on vibration/shock and/or temperature.

SOMETIMES you can get lucky and find that simply opening the device and unplugging/replugging cables can cure a variety of problems. If you're desperate, resoldering dodgy-looking joints can fix things, but might also ruin it.

This advice was free, and my liability is equal to the price you paid for it :-)

[Zumi]

I got exactly the same problem that was described in the opening post.
So, my Zaurus is dead.

Anybody found out anything about the repair, except from sending back to Sharp Japan?

...but I've got an idea
I'm still able to go in the menu where I start the reflashing process (Power+OK) and the reflashing process starts (I try it with pdaXrom). It stops with some error, it can't decide what is my Zaurus (C700, 750, etc.) version, this must be because of the corrupted NAND flash.

But... is it possible to alter a setup script in a way that it doesn't setup anything but boots up a system entirely from the SD or CF card, not using the NAND?

[Zumi]

Hello! Good news!
For all the Z owners with this problem, there's hope!
I managed to revive my Zaurus. I don't know _exactly_ what did it, because I wandered a lot in the Service menu.

I write here the process of my restore. (which I think lead to success)

- The objective is to clean up the NAND.
You have to get into the service menu for this:

1. Open the battery cover
2. Take out the battery for about 5 seconds
3. Put it back
4. Hold down the D+M keys on the keyboard
5. Close the battery cover while holding the keys
6. You will find yourself in the service menu
7. Get in the 3rd page (with the "up" arrow)
8. Choose "7.EXTRA MENU"
9. Choose "1.Zaurus Test"
10. Get to the 2nd page and select "10.NAND Flash Full Erase"
11. This is the tricky part. If this doesn't work for you (gives an error message) then I don't know... There are other NAND Erase options in the Service menu, try all (at least I tried every one I saw). If it doesn't help, try them again (especially this NAND Flash Full Erase). I tried it a good couple of times before it worked. If you can put your NAND in a good shape, you won.
12. If you managed to do it, then you won't see error messages in the different parts of the service menu.

Your Zaurus is most likely in a better, but still bad shape now, so you need to recover it.
- The C+D recover:

1. Get the recovery package from here: http://pocketworkstation.org/files/recover/
2. Read the included README. Read it again. You really want to do it? If you got this far, I think you do.
3. Copy the files on a CF card and put the CF in the Zaurus
4. Use your AC adapter in the process and make sure your battery is not low
5. Open the battery cover and take out the battery for about 5 seconds
6. Put it back
7. Hold down the C+D keys on the keyboard
8. Close the battery cover while holding the keys
9. The mail and charge leds will continously light and will turn off after 30secs-2mins

Time for a NAND Restore!
The NAND backup file that has everything on your NAND flash. You can download original NAND files for different Z versions from here:
http://downloads.conics.net/pda/zaurus-sl-...iginal-backups/
Use only the same version as your Zaurus!

1. Put it on a CF card (make sure it is formated FAT16!)
2. Get into the Service menu again, make sure you are using AC adapter.
3. Go to the 3rd page in the service menu and select "10.NAND Flash Restore"
4. If the Z doesn't find the NAND image, although it is there, try reformat it. If that doesn't help, try to get a different CF card.
5. If the restore process fails ("format error" with red letters) then the NAND flash is still not OK, go back to the previous steps
6. If the green line reach the right side of the screen and it says OK, then your Zaurus is living again!

You can now flash your favourite ROM on your revived Z!
This tale was about a SL-C700, I read somewhere that you can use SD card for NAND Restore with greater versions.

I hope you will have luck with this too!
Zumi

[Zumi]

So, the bad news...

The repair is only temporary. It starts degrading very fast. I was able to put on it a distribution two times but it freezed and beginned the usually partition error stuff.
So, this seems to be a real hardware problem, not only a software one. Any ideas how to repair it? Or how to run some NAND flash independent distribution on it?

Zumi, with a bricked Z

[jasonakay]

So, the bad news...

The repair is only temporary. It starts degrading very fast. I was able to put on it a distribution two times but it freezed and beginned the usually partition error stuff.
So, this seems to be a real hardware problem, not only a software one. Any ideas how to repair it? Or how to run some NAND flash independent distribution on it?

Zumi, with a bricked Z

Great. My C760 crashed on me yesterday. It also has bad NAND flash! I suspect I could purchase a new C1000 for what it will cost me to send the C760 to Japan for repair. Are there any other options?

Jason (also with a bricked Z).

[Stubear]

Great.  My C760 crashed on me yesterday.    It also has bad NAND flash!  I suspect I could purchase a new C1000 for what it will cost me to send the C760 to Japan for repair.  Are there any other options?

Jason (also with a bricked Z). 

Bad NAND flashes are more often the result of CF or SD card problems than NAND erros in my experience.

Try reformating for CF or SD card before copying the NAND file over and try again - it helps of you haven't turned the Z off after the Bad flash, just pop the CF card, reformat, copy nand file, and reflash.

Happened to me about 6 or 7 times so far, I guess the CF gets too fragmented after a while.

Stu

[jasonakay]

Bad NAND flashes are more often the result of CF or SD card problems than NAND erros in my experience.

Try reformating for CF or SD card before copying the NAND file over and try again - it helps of you haven't turned the Z off after the Bad flash, just pop the CF card, reformat, copy nand file, and reflash.

Happened to me about 6 or 7 times so far, I guess the CF gets too fragmented after a while.

Stu

Well, I've done a full erasure of the NAND and I still get two bad blocks (#1 and #3) out of eight. That's before or after I do the recovery and NAND restore.

Jason.

[jasonakay]

9. The mail and charge leds will continously light and will turn off after 30secs-2mins

The first time I tried the recovery, this worked as you described. I was able to perform a NAND restore as well, but I couldn't install a ROM. I am running through the whole process again -- full NAND erase; recovery; NAND restore. This time, while doing the recovery, the mail and charge lights have been lit for over 10 minutes and are still! Any idea why this would happen?

Thanks,

Jason.

[jasonakay]

Well, now it's really toast! All 8 blocks are bad. When I try to use the service menu to erase the NAND all I get are errors. I think this one is done. I can't really afford to send it back to Japan for repair. Can someone recommend where in Canada or the USA I might find someone who can solder a new NAND chip (and remove the old one) for me? For that matter, where would one find a compatible NAND chip?

Or should I just sell my Z for parts?!

Thanks,

Jason.
C760 (not doing so well...)