So, I have my main N900 since June 2010, but broke the USB a long time ago (2013 I think). Other than that and a suspecting GSM failure (very rare, but I guess it's happening... been like that for a year. I guess it will eventually die and only show up the SIM card error).

About the USB, unfortunately, the repair shop f****d up the motherboard pins, so now fixing it is going to be one hell of a job, which neither me nor my father have any expertise on (I guess it'd be similar to oh2btg's fix, except he did a mistake and swapped some wire "positions", as far as I know). Oh, if only I didn't go to that repair shop... the motherboard pins were absolutely intact before going there, so it'd be just slapping a new microUSB in there. My father could have fixed it instead, but he was a little afraid of doing it since his vision had better days and nowadays everything is so tiny.


Anyway, it's running CSSU Thumb and I'd like to flash it back to stock, mostly because Rockbox keeps crashing, but also because I'd like to start it fresh again.

Obviously I don't have a working USB, and right now I don't have hardware or expertise to use the back "pins" you see when you remove the battery.

I do, however, have a spare N900 (that I bought used in 2013, with a working USB, but the GSM module failed much sooner, so it's useless as a phone and serves only as a heavy iPod, which is why I don't use it.

Anyway, I have backupmenu installed on my main N900, and was wondering how i'd go about this.

I could try doing a clean install on my spare N900, install backupmenu on it and create a backup image, and then put it on my main one, which does not have USB.

However, I read that backupmenu does not mess with the kernel and I am afraid of bricking it, so I'd love if any of you could help me guide through the process to avoid any mistake. Usually I'd just do this crap on my own and fix any mistakes on the way, but without the working USB I can't afford to get in a boot loop! (I charge all my batteries externally, by the way), so I'll have to hit everything perfect on my first try!


Any help would be appreciated!


And now for my second request, but I'd only do this if I manage to flash the phone back to stock successfully: Get help removing the 1150Mhz limit on the power kernel, I'd love to try higher frequencies, perhaps reach 1300Mhz (after all, the Motorola Droid, which uses the same OMAP 3430 as far as I know, reached 1.3Ghz!) (and yes, I know it heats up and will potentially damage it, or even create a black hole, but the phone is already old and the GSM is showing its early stages of death, so might as well go out with a bang!).


Sorry for the long topic!

BackupMenu clone from device to device B is a lottery. It is supposed to work in theory, all you need is to make sure your kernels match. But in practice you can run into all sorts of weird problems.

Take (real) care that both devices run the same kernel. As kernel is not on rootfs/optfs and not covered by backupmenu.
-- pichlo beat me

Another thing is the hardware revision of devices.
Please check them with
If they are the same, good.
If not if may work (it did it to me) but it may also cause some problems (at least that it was I remember to have read).
I switched twice from device to device. Once with same HW revisions. And once from 2101 to 2204. The latter forced me to flash the kernel via USB.

rather wait until you can learn how to fiddle with those 'extra' pins on back of device.

meantime, you're sure your rockbox issues are thumb-related? likely something else is up instead.

perhaps for the time being rather investigate the real cause of that crash, etc. freemangordon would undoubtedly be willing to look at your case if there's reasonable reason to believe thumb is at fault

Ah that's sad, might be related with different HW revisions? AFAIK mine are not the same.

How would I go though - if I need matching kernels, I'd have to install the cssu-thumb kernel on the secondary N900, and then make a backup and apply on my main one (which has cssu-thumb kernel). However, after this, how would I remove that kernel and apply the "normal" kernel-power, non-thumb?


Because I've read that removing the cssu-thumb kernel is not as straightforward as the other ones due to all that errata behaviour change (I'm a little outdated on this, will have to read again after a while).

Or I guess I should just man up and try using the pins behind the battery...

EDIT 1: Indeed, I'll check the HW revisions of both devices and later put them here.


EDIT 2: I believe it is caused only on thumb, I was not the only one with this issue and it has only happened on thumb so far. However, the phone hasn't been flashed in a while and it is no longer 'fresh', had lots of programs that were installed and uninstalled, etc. So to clear out everything a flash, or the closest to a flash I can, would be optimal.