Hello All,
I decided last night to revert from my penguinbait SD boot to booting the onboard flash. I don't use my n810 much in an interactive means any more and found that I could never get things operating 100% stable with the SD boot.

So, I do some quick googling to find the stock n810 images from nokia and the upgrade instructions ( it'd been a while ). Everything was going well until I tried to put my n810 into usb flash mode. I quite literally will not enter usb flash mode. No matter if it's already plugged into the PC or not, nor powered or not. Every time I try, it boots to the boot device selection menu and as soon as I release the home button, it goes into network recovery mode with telnet enabled.

Since I couldn't get USB recovery mode working.. I thought I might as well boot to the onboard flash from the boot menu and from there, use the internal flash tools to restore at least a completely stock kernel and initfs. (Note, I'd not done any kernel/initfs customizations aside from the penguinbait SD boot process)

Before I could do this however, I found that I was having issues even getting the n810 past the 'Nokia' splash screen. No boot menu, etc. It would sit at the 'Nokia' splash screen for about 30 seconds, then power off.

After many failed attempts and various boot tests in different configurations ( powered by adapter, USB plugged in, etc.. ) With the unit powered down, if I insert the power adapter the unit enters an endless reboot loop, each time displaying the 'Nokia' splash for 30 seconds, then resetting and doing the same again. I found that the only way I can reliably boot my n810 now is if it's plugged into my computers USB port when I press the power button. As long as it's connected via USB first the unit boots completely normally.

One other item I've noticed is that the unit will not enter USB drive mode. Actually, there is nothing displayed in my linux boxes messages or dmesg logs upon plugging in the n810.

I found bug 3026 which seems to indicate that some n810's have problematic USB hardware. I'm beginning to wonder if my system falls into this realm.

I've recently been using the n810 purely for it's GPS abilities in my vehicle. It stays plugged into a cig-lighter power adapter and powered on for days on end in my car. While the weather here has been winter and spring in nature, the inside of the vehicle has been up in the 80's and 90's on the warmer days so the n810 has experienced some environmental heating.

Before trying to enter USB flash mode, the unit was booting and acting quite normally. I hadn't plugged it into a PC via USB for quite a while, and didn't try this until after attempting to enter flash mode, so I don't know if that would work before hand.

I have managed to use the kernel_flash and initfs_flash tools to restore the stock kernel and initfs, but the n810 still refuses to boot without being plugged into a PC over USB. I've also tried simply applying power with a USB power adapter to the n810's port to try and figure out if it was simply the power part of the connection that permitted it to boot, but this failed.

I set the debug level higher for the USB stack per the above linked bug.
From this, I monitored the dmesg output upon inserting the USB cable to a linux box. The following is all that is output:

So, the n810 sees it is plugged in, but nothing else seems to occur.

I sincerely apologize for the long post, but I wanted to make sure I provided as much detail as I could in hopes that someone has seen this issue and gotten past it. I've had my n810 for about 18 months and I'm certain there's no warranty left on it, so if hardware replacement or repair is required, I guess I'm a bit hosed unless this is a known hardware flaw and covered by that premise.

Thanks in advance for any advice. If I've left out some detail, please don't hesitate to ask.

Thanks,
LK

Made the mistake of letting my n810 battery drain completely. Now I can't get it to boot even when connected to my PC.

Any help would be greatly appreciated..

Thanks,
LK

I've always found starting the flasher on the PC first, then (with USB cable connected) running the flasher (this assumes you're using Linux); ie:


1. run (as root) "flasher -r /path/to/rootfs.jffs2 -f" (it should say something like "no device found; waiting")

2. Insert USB cable into N810 and PC

3. Power on N810 (no button pressing required, it should just flash)


I really hope that helps, though it sounds like you've probably tried it already. If you're using Windows, maybe trying with a live CD and the Linux flasher*?

*I don't have the most faith in Windows stuff

Hello Capn_Fish,
Thanks for the response. Definitely gave that a shot, but the n810 isn't getting far enough into the booting process now to be recognized at all.

An no winbloze junk here... pure linux for me.. I keep an eye on the dmesg output of the linux box with USB connected during the n810's bootup and not a single message appears.

I've tried multiple USB ports on 2 different linux boxes and multiple USB cables to rule out any of those points of failure.

At this point, when I plug power into the n810, the Nokia splash hits, and stays up for about 5 seconds, then it resets... rinse, repeat.

I really think this one is busted. My expectation is that there is some issue with the USB chipset in the n810, but haven't been able to confirm that yet. I've got another one on the way and as soon as it gets here, I may deconstruct this failed one unless someone thinks I've got a chance at Nokia repairing it... ( had it for > 18 mos ).

Thanks,
LK

Before you tear your tablet apart, try changing out the battery. While I haven't seen this problem on this device, I have seen mobile phones go into the reboot loop when the battery is nearly dead (and won't take a charge). This may not solve the initial problem but it should get you to where you can do more troubleshooting.

Hello Kansasdude,
Thanks for the idea. I have been able to get the battery charged and it produces the same results.

I've acquired another n810 to fill my needs, but would love to get this one working again. Any other ideas greatly appreciated.

LK

What distribution are you running. I had loads of issues lately when I re-flashed my N810 on Ubuntu. I ended up needing to blacklist a couple of modules before it would see the N810. Can't remember what they were, but I found the info on here. A quick search should find it.

Are you running the flasher command as root?

Hello gazza_d,
I run Fedora 12 x86_64 right now... Waiting for 13 to go final. I've had luck flashing my new unit without any changes to the OS. And yep.. Run'n the flasher as root.

Really think'n the USB chipset is hosed some how on the n810.

Thanks,
LK