I am trying to find some info on the C860 on ROMS. Basicly I understand that you can do an ROM upgrade via the regular (hold the ok and turn on), or you can do a NAND restore via the D+M service menu. Question is, what is the difference between doing that this 2 ways. What are the benefits and drawbacks of each method?

Assumptions (not being a c860 owner at present): I assume that the 128 MB NAND is partitioned off, part for the ROM (root) and the rest for /home.

The main difference is that the NAND is a snapshot of your whole flash chip - including the diagnostic menues, the bootloader, the normal filesystem and the backup maintanece filesystem.

The ROM however is just the files on the normally visible part of the flash chip (ie / ro filesystem and the /home rw filesystem (actually the /home /var and /dev are all tarballed under /root as hidden files but they come with the ROM)

The advantage of the ROM is that is much faster than the NAND restore (usually 30MB against 128Mb+) and the ROM update doesn't need to be done from the diagnostic menus (D+M) which Sharp doesn't really approve of simple users using. The diagnostic menus contain some options that can turn your Zaurus into a brick, so don't experiment in here unless you are ready to shell out extra cash to get you Z back on line or have the expertise/patience to get it back yourself (note: there are a lot of posts here about people who brought their Z back from the dead)

The advantage of the NAND restore is that aftre the restore the Z is exactly as it was when you made the NAND backup. All the packages you had installed, all your settings, docs, addressbooks enteries etc will be there - this is a good reason to be careful about sharing NANDS!

The format of the NAND is also different from the ROM, the ROM is a jffs2 or cramfs filesystem while the NAND contains raw data from your flash partitions as well as certain header files (which casue the NAND file to be bigger than 128MB)

hope this is helpful

Stu

One other advantage of the scripted ROM install is that you get a "clean" original just as it left the developers' hands.

Like a fresh install of a distro to a cleand hard drive.

The NAND is more like restoring a Ghost or Drive Image copy to a HD. You get "warts & all" when youre done.

Ah ok, I understand it now. One other question. What other than the OS and user space is stored in the NAND flash area. This is my asumption, and corect me if I am wrong. In NAND, you have the code that handles scripted OS (ok+poweron) upgrades, the bootloader, the OS and the user area. In my mind, the bootlader and the os upgrade menues may be the same component, but not having one of these units I dont know.

The non changable code is the D+M HW menu, and any lowlevel code used to recognize the HW componenets, kind of like BIOS.

Is this right?

If this is the case, how come nobody has re-written the scripted OS loader menu (ok+poweron) to be in English? Is this even posible? If it is I would like to start hacking it up, once I get my C860 this month. Forgive me if this has already been handles in the cacko ROM's.

I do know that if you have repartitioned the system, the NAND will restore the partition sizes as well as their contents. There are references to a non writable "P2ROM" in some C series (including photos of the chip on a Japanese site) but I have not been able to find out if the C860 has this chip or not.




Have not yet gotten really clear answer(s) on exactly how much and of what is in NAND space. Possibly everything? Would *like* to find out but haven't worked out just how to do it so far.




Good question. To find out might risk terminal brickage if wrong. (G) I can give you citations to what data I have found, if you want.




Hummm. Have not run the OK+PWR sequence since loading Cacko. Will have to try & see. But maslovsky would be able to tell you, if anyone can. He is the mighty wiz in that area. (G) Cacko 1.22 has the first splash screen in English now and once that was posted as not expected to be do-able, so ......

Keep asking the questions. Eventually we'll get some real answers (G).

Geeks GOTTA *KNOW*!!

The diagnostic menus are included in the NAND, I know this cause I flashed my C760 with C860 NAND and the diagnostic menus changed from white (c760) to red and reported my machine as a C860. To flash back I had to rename my C760 NAND to systc860.dbk to get it restore the NAND.

I think from discussion on the old Sharp forums that there is another chip, but I can't be 100% sure I'm not halucinating.

There were some specs of the C750 flash layout on a Japanese site. Extending from this page klause created some scripts for extracting recovery files for Cxx0 zaurus http://pocketworkstation.org/files/recover/

The openzaurus people or the Cacko people may be able to give you more info on the bootloader but a perl script I found for dismembering the NAND was improved by iain_benson over at http://externe.net/zaurus/forum/viewtopic....&highlight=nand. But basically the layout of the NAND for a C760 and C860 is


The kernel defaults to English, so if you remove Sharps custom start screen then you can see the kernel info go by in English. The Cacko rom have replaced the Japanese "please wait" Sharp screen with and English version and a number of kernel images remove it altogether.

I haven't seen the ROM flash menu in anything but Japanese yet, but I imagine that it's also possible to change that too.

Sorry for thr disjointed response, recollecting lots of very old discussions and links. Hope dome of this is helpful to you

Stu

I appreciate all the info here... You have given me alot of good and usable info. I guess now, I should hack apart a NAND backup and see what I find.

Hi,
where to find all information about nandlogical and boot-process?
nandlogical:
1) the second argument always is READ or WRITE?
2)if I copy from device mtd1 at address 0x70000- what I get?
(or maybe full map of /dev/mtdX ???)
3)which mtd's are logical devices and which aren't?
4)Is always secure (for zaurus) to test with nandlogical when reading?
(I have never used nandlogical yet)
boot-process:
where to find full description?
where are located kernels (Sharp and this one from Cacko)-
maybe it is possible to mount /dev/mtdx and copy Sharp's kernel to cf card?
(I am using Cacko 1.22 on C860)
Thanks in advance
Janusz

Hello

See externe.net/zaurus/flash especially the .jpg where I tried to explain that. It's for a 6000 but it should also apply.

Regading the power+ok menu - I have a 6000W which had that in japaneese. I flashed the 6000L part (will post the parts extracter soon) and now I have it it english so it should be possible on a Cxxx - however if the 6000 code is different you could turn your Z into a brick.

Guylhem

Thanks for information!
About two weeks ago I have seen:
http://www.h5.dion.ne.jp/~rimemoon/zaurus/memo_006.htm
and I have done translation using:
http://babelfish.altavista.com/tr .
I think that I can all understand
(eg: addresses where dd do not work for mtd1, kernel file suitable for "memory map"), but:
1)maybe someone who speeks in both languages could do better translation?
2)this page is from 2003 and seems to be that more is known -
maybe an Expert could send for us this "secret" information?

I am looking for "a good disassemler" for arm-ELF files(I think that Experts do not like to talk
to ordinary users ....),
maybe someone could give "a good link" for it?

Maybe someone know something about structure of paraminf.bin
or have source modparam.c? (I am looking what the program modparam do
with paraminf.bin-file....)

Maybe someone knows something about verchg (more that verchg --help)?

Thanks in advance
Janusz