how to unfreeze my BBB?

So, in an attempt to upgrade the OS on my BBB, I managed to get it to lock up.

When I try to boot, the LEDs look like normal for a few seconds, but then LED2 comes on solid, and the others are off.

This occurs whether or not I plug in my flash drive.

When I hold down the boot button, I get no LEDs at all.

So…I’m guessing that I’ve corrupted some system files and am entering an infinite loop. Given that the workings of the BBB are essentially hidden from me (I can’t access it via ssh or even ping), what is my best course of action?

Thank you.

reflash with a current image or an image of your choice

On Tue, 14 Feb 2017 15:34:47 -0800 (PST), mzimmers
<mzimmers@gmail.com> declaimed the following:

So, in an attempt to upgrade the OS on my BBB, I managed to get it to lock
up.

When I try to boot, the LEDs look like normal for a few seconds, but then
LED2 comes on solid, and the others are off.

This occurs whether or not I plug in my flash drive.

When I hold down the boot button, I get no LEDs at all.

So...I'm guessing that I've corrupted some system files and am entering an
infinite loop. Given that the workings of the BBB are essentially hidden
from me (I can't access it via ssh or even ping), what is my best course of
action?

Thank you.

  Is "flash drive" a USB memory, or a microSD card?

  If USB -- create a microSD card with a recent image and see if that
will boot (you might need to hold down the boot select button to force
microSD).

  If the microSD image will boot, follow the instructions to convert it
to an eMMC flasher image, and reboot. Then remove the microSD card after
the flashing is complete and again reboot -- this time it should be off the
eMMC.

This is one reason to buy, own, and use a serial debug cable, or module.
You'd know exactly where the boot process was stopping. Then if you put the
kernel in verbose mode( remove "quiet" form the boot args ), you would
probably know exactly why the board is hanging. Chances are pretty good
that the image flashing just failed for something like insufficient power
while flashing( using USB power ) or maybe a picky, or bad sdcard.

Hi, Dennis - thanks for the reply. The image is on a microSD card. I followed the directions here. I got the image from here. It doesn’t boot.

William: I do in fact own a debug cable. I’ll try plugging it in and see if I can see anything. I’ve never worked with boot arguments; can you tell me where they’re kept?

mz

Here’s a snippet of terminal output.

copying: [/dev/mmcblk0] → [/dev/mmcblk1]
lsblk:
NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT
mmcblk0boot0 179:8 0 4M 1 disk
mmcblk0boot1 179:16 0 4M 1 disk
mmcblk0 179:0 0 3.6G 0 disk

-mmcblk0p1 179:1 0 96M 0 part /boot/uboot
`-mmcblk0p2 179:2 0 3.5G 0 part /


df -h | grep rootfs:
rootfs 3.4G 2.1G 1.2G 64% /

Error: [/dev/mmcblk1] does not exist
writing to [/dev/mmcblk1] failed…

I don’t know what to make of it…is it possible that my SD card is mis-formatted? And if so, can someone direct me to the directions for properly formatting it? It’s a 64GB.

Can you please provide the full serial log when you tried to boot with
that card? (it's picking up the eMMC, but not the microSD on bootup)

BTW, what brand/model is that 64GB microSD.. SDHC is only supported
to 32GB, while "some/specific" 64GB SDXC cards work, it's not 100%
supported on the am335x silicon.

Regards,

root@beaglebone:~# lsblk
NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT
mmcblk1boot0 179:16 0 2M 1 disk
mmcblk1boot1 179:24 0 2M 1 disk
mmcblk0 179:0 0 14.7G 0 disk
`-mmcblk0p1 179:1 0 1.7G 0 part /
mmcblk1 179:8 0 3.6G 0 disk
`-mmcblk1p1 179:9 0 3.6G 0 part

root@beaglebone:~# mkdir a

root@beaglebone:~# mount /dev/mmcblk1p1 /root/a/

root@beaglebone:~# cd a/

root@beaglebone:~/a# nano boot/uEnv.txt

You're looking for( Whichever line has this and is not commented out)
-> cmdline=coherent_pool=1M
quiet

Remove the "quiet" off the end, then save / exit the file then reboot -
From the emmc of course. Observe the serial debug output. Also, at least
one person I can remember reported issues with booting without the quiet
option. So perhaps you may want to put it back after you're done getting
your verbose information ? Up to you.

By the way, DR. Molloy seems to be a good guy, and has a lot of useful information. But much of that information is dated, and wont work with current images.

What this boils down to is that if you’re not an expert, or at least proficient with Linux. You’re very likely to run into many problems. It may be best just to pose your questions here on the groups. Robert knows all the details of the images, and often times I can at least help pick up his slack. As well as I probably have a lot of hands on experience with most of the peripheral modules, on current Linux image.

Additional information I unintentionally left out, and be VERY CAREFUL with using he -rf flags with rm. Make sure you’re removing the correct directory. This can completely hose your Linux rootfs if you’re not absolutely sure what you’re doing. This is also partly why I traverse into a new mount when working with system files. So I don’t accidentally modify anything on the live system . . .

root@beaglebone:~/a# cd …
root@beaglebone:~# umount /root/a
root@beaglebone:~# rm -rf a/

Hi, Robert -

Can you please provide the full serial log when you tried to boot with
that card? (it’s picking up the eMMC, but not the microSD on bootup)

The full log is in this file.

BTW, what brand/model is that 64GB microSD… SDHC is only supported
to 32GB, while “some/specific” 64GB SDXC cards work, it’s not 100%
supported on the am335x silicon.

The card I’m using is found here.

Hi, Robert -

Can you please provide the full serial log when you tried to boot with
that card? (it's picking up the eMMC, but not the microSD on bootup)

The full log is in this file.

Ahh, i see what you did..

Card did not respond to voltage select!
Card did not respond to voltage select!

1: u-boot isn't detecting the SanDisk Ultra 64GB microSDXC

2: You wrote the "flasher" image directly to the eMMC.

So now on every boot, the eMMC is trying to flash the "microSD"

BTW, what brand/model is that 64GB microSD.. SDHC is only supported
to 32GB, while "some/specific" 64GB SDXC cards work, it's not 100%
supported on the am335x silicon.

The card I'm using is found here.

SanDisk Ultra 64GB microSDXC (SDSQUNC-064G-GN6MA)

I don't remember off hand what model SanDisk i had tried..

But what you should do to "fix" this issue you caused..

Grab a normal non microSDXC aka a microSDHC

Grab this specific image:

https://rcn-ee.net/rootfs/bb.org/testing/2017-02-12/iot/BBB-blank-debian-8.7-iot-armhf-2017-02-12-4gb.img.xz

Write it with https://etcher.io/ to a normal microSDHC

Plug it into the beagle, hold down boot button, insert power, wait for
4 led's, lift up boot button..

Let it flash the eMMC and get things back to working state..

Regards,

Thanks, William. But, given that the BBB isn’t booting, how am I supposed to get to that file to edit it?

Thanks for the quick reply, Robert. I have a few questions:

  1. any idea how I went wrong? I thought I was following the directions faithfully.

  2. I’ll try to find a “normal” microSDHC card locally, but I might have to order online, which will of course introduce a delay. Is there any harm in continuing my use of the card I have?

  3. In some of my readings yesterday, I read that I’m supposed to uncomment the final line of the /boot/uEnv.txt file on the microSD card. Elsewhere, however, I read information that claimed otherwise. Can you render judgment on this?

  4. I notice the link you gave for the image is from the testing area. On a scale of 1 to 10,000,000, how stable is this image?
    Thanks a ton…this is all really valuable information.

Thanks for the quick reply, Robert. I have a few questions:

any idea how I went wrong? I thought I was following the directions
faithfully.

It's my guess, you wrote a new image to the 64GB microSDXC. Following
the directions you edited /boot/uEnv.txt, BUT not knowing the
microSDXC had failed to be detected, thus you edited the eMMC's
/boot/uEnv.txt.. Now it's stuck in a loop..

I'll try to find a "normal" microSDHC card locally, but I might have to
order online, which will of course introduce a delay. Is there any harm in
continuing my use of the card I have?

Well, other then U-Boot/Kernel not detecting the card.

The am335x does not officially support microSDXC cards, so what looks
to have happened. Some of us tested a few microSDXC cards, when they
first came out a few years ago, and while some worked. However it
looks like SanDisk dropped that compatibly mode they had used in their
first gen microSDXC cards.

Anywho, all the BBB/am335x doc's clearly state it only supports
"microSDHC" cards (2gb -> 32gb).

background:

In some of my readings yesterday, I read that I'm supposed to uncomment the
final line of the /boot/uEnv.txt file on the microSD card. Elsewhere,
however, I read information that claimed otherwise. Can you render judgment

http://elinux.org/Beagleboard:BeagleBoneBlack_Debian#Flashing_eMMC

I notice the link you gave for the image is from the testing area. On a
scale of 1 to 10,000,000, how stable is this image?

Wrong Scale for this situation. :wink:

On a scale of, currently not usable -> usable... that image is usable..

After you flash the recover, you can flash any image you want..

Regards,

Thanks for all the good information, Robert. I’m still hitting a snag. Here’s what I’ve done:

  • got a new microSDHC from Walmart (32 GB Samsung EVO)
  • downloaded your Debian image
  • used Etcher to put it on the SDHC card
  • ejected it from my desktop, put it in the BBB and tried to boot from it.
    Nothing happens. None of the LEDs come on, nor does the LED on the card reader.

How long am I supposed to hold down the boot button before something happens? I gave it about 15 seconds before the tool I was using slipped off the button.

Thanks.

oh less then 5 seconds after you plug in power..

Regards,

Well…that’s discouraging, particularly that I’m not getting a LED on the card reader when I slide in the card.

Any suggestions?

Thanks…

mz

Where is the card reader being inserted into?

Gerald

Hi, Gerald - it’s in the USB port.

The card reader I got can be found here.