Hi, I'm new of the forum and of the maemo world.
My name is Mirko and I have a very big problem.
I'm Italian and my English is not perfect, if there is any Italian who can help please contact me in private
My problem is very simple: I installed u-boot and reboot the n900 I get my u-boot screen where you get to say "Loading Kernel ..." and after a few seconds the phone goes off.
I read that to fix this you have to "re flash", the problem is that connecting the N900 with usb port, n900 reboots always coming back to U-Boot.
According to the guides, the first screen that says "Nokia" should also appear in the USB logo on the top right, but this does not appear.
What can I do to fix my n900?
Thank you all.
Mirko

hello and welcome

are u pressing the 'u' key on your N900 keyboard while connecting the USB?

Yes, of course, I forgot to say, but absolutely nothing changes, carry out u-boot as if nothing had happened. :\
Mirko

many people say take out the battery leave it for a minute or two and try again

1 - remove battery
2 - connect usb cable to pc
3 - press and hold down u key on N900's keyboard
4 - reinsert battery (don't release u key)
5 - wait at least 4-5 secs (don't release u key)
6 - release u key only if usb logo is stable on screen

This should work and if not you have probably low battery (If battery charge is too low N900 doesn't activate flash mode)

m4r0v3r, I've leaved the battery for 10+minutes, I plug the usb cable, pressed the "u" key and re insert the battery, but nothing.. :S
Mirko

@Fabry:
reinsert battery (don't release u key) <- The N900 will not turn on automatically.. :S
Edit: If I've low battery, how I can load it?
Mirko

You can reflash the kernel (as per wiki reflashing instructions) as normal.

Just ignore uboot, or plug the N900 in and don't bother turning it on.

I had this happen once (I made my own uboot+kernel image, used a zImage - had to be converted to uImage, and it wouldn't be able to load the zImage, so it would get stuck on the U Boot screen). I don't remember literally every second of what I did, but I do remember that I reflashed the stock PR1.3 kernel (just kernel, no need to wipe everything else), using the flasher utility, as normal. I don't remember if I let it boot into uboot or not. I'm pretty sure if it tried to start uboot, I just shut it down (pulling battery was the only way), and put it back in, and DIDN'T turn it on.

If everything is normal, your N900 should still be ABLE to enter flashing mode the moment the flasher utility tries to flash it. The hold-u-key process is just an extra layer of just-in-case precaution. It's not necessary.

In the future, look up what your N900's hardware revision number is, and check which uboot version you're using (the latest one including Matan's, e-yes', and other patches doesn't work on one of the hardware revisions).

Also, remember if you're making your own kernel+uboot images, that the extracted zImage has to be made into a uImage using "mkimage" first.

- Edit -

If your battery is horribly low, however, I don't know how to help you. You'd either have to charge it in another Nokia phone that takes the same battery, or in a special charger. Or you might get lucky and the N900 can get enough power from the USB port during flashing even with no energy what-so-ever.

In my experience, when the kernel image attached to u-boot is good, the N900 will start charging automatically. So you'll plug in the charger, uboot will come on, then screen will go dark (but still show the uboot screen, just without backlight), but the N900 will charge (this is just like when the N900 is off, and you plug it in, and it starts charging. What it does, is loads the kernel partway, then drops you into a basic charging mode - when uboot intercepts the kernel first, it takes over the screen long enough to display itself, but then when it launches the kernel, it sees that it got booted from a charger-plugged-in event, and just drops into charging mode). From here, you can let the battery charge long enough to boot normally.

However, if the kernel ISN'T loading, I'm not sure how much it can charge without it. I THINK the hardware has a very basic charging capability beneath what is normally controlled by BME. So it MAY be able to charge, even if it doesn't show anything, enough to boot/flash - but no guarantees on that.

u won't be able to reflash ur mobile with low-battery

u should charge it out of the phone then flash ur mobile

How I can Mido? I haven't any friends with n900..
Mirko