how to unfreeze my BBB?

[mzimmers]

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.

[evilwulfie]

reflash with a current image or an image of your choice

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[Dennis Lee Bieber]

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

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.
--
Wulfraed Dennis Lee Bieber AF6VN
wlf...@ix.netcom.com HTTP://wlfraed.home.netcom.com/

[William Hermans]

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.

[mzimmers]

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 

[mzimmers]

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.

[Robert Nelson]

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,

--
Robert Nelson
https://rcn-ee.com/

[William Hermans]

On Tue, Feb 14, 2017 at 7:02 PM, mzimmers <mzim...@gmail.com> wrote:

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 

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.

[William Hermans]

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.

[William Hermans]

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/

[mzimmers]

Hi, Robert -

On Tuesday, February 14, 2017 at 7:33:28 PM UTC-7, RobertCNelson wrote:

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.
 

[mzimmers]

On Tuesday, February 14, 2017 at 7:58:39 PM UTC-7, William Hermans wrote:

 (some excellent directions on modifying boot arguments)

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

[Robert Nelson]

On Wed, Feb 15, 2017 at 11:04 AM, mzimmers <mzim...@gmail.com> wrote:
> Hi, Robert -
>
> On Tuesday, February 14, 2017 at 7:33:28 PM UTC-7, RobertCNelson wrote:
>>
>> 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..

[mzimmers]

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.

[Robert Nelson]

On Wed, Feb 15, 2017 at 11:25 AM, mzimmers <mzim...@gmail.com> wrote:
> 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:

https://en.wikipedia.org/wiki/Secure_Digital#SDXC

https://en.wikipedia.org/wiki/Secure_Digital#Ultra_High_Speed_.28UHS.29_bus

> 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?

The doc says:

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. ;)

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

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

[mzimmers]

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.

[Robert Nelson]

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

[mzimmers]

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

[Gerald Coley]

Where is the card reader being inserted into?

Gerald

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[mzimmers]

Hi, Gerald - it's in the USB port.

The card reader I got can be found here.

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[William Hermans]

Well that implies you're able to boot from sdcard. I guess I should have written that too ?

[Gerald Coley]

The board is designed to boot off the SD card connector on the back of the board, not the USB port.

Gerald

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[mzimmers]

Oh man...what a moron I am.

I unplugged the USB device and put the card into the connector you mentioned. Even without me holding down the boot button, it seems to be loading (probably because it couldn't boot from the eMMC). I'm now getting the 1-2-3-4-3-2-1 flashing of the LEDs...will report back when that's done.

Thanks, Gerald.

[Gerald Coley]

You bet!

Gerald

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[mzimmers]

OK, so after some time, the LEDs stopped flashing. When the SD card is loaded, I can boot, and access the BBB via ssh, and all that good stuff.

When I remove the card, though, the BBB is acting the same way as before I flashed it.

Robert: could this be because I inadvertently uncommented out that line in the wrong uEnv.txt file? And if so, how do I navigate to the file system on the eMMC so I can recomment that line? I'm still learning about devices and file systems on Linux.

[Robert Nelson]

laughs...

It sounds like you transferred the "eMMC" image to the "microSD"...

Like had said:

Plug in microSD
Push down boot button
Apply power
Wait for 4 LED's
Remove finger from boot button..

So you didn't do the boot button correctly, thus on bootup the "eMMC"
flash the "microSD" ;)

So go back to step 1 ;)

Use etcher.io, reflash the microSd and try again. ;)

[mzimmers]

Heh...OK, I think I got it right this time. The BBB now boots up without the SD card. I'm now running Debian 8.7, which was the goal, so I can end this thread. 

Thanks to everyone who helped on this. I'm not really experienced with the Google groups; do I do something to mark this as answered or solved or anything?

[Dennis Lee Bieber]

On Wed, 15 Feb 2017 14:45:51 -0800 (PST), mzimmers
<mzim...@gmail.com> declaimed the following:

Google Groups may be echoing this, but it is not necessarily a Google
group... I'm accessing via gmane.comp.hardware.beagleboard.user -- using
the gmane NNTP (netnews) server.

[William Hermans]

On Wed, Feb 15, 2017 at 6:55 PM, Dennis Lee Bieber <wlf...@ix.netcom.com> wrote:

On Wed, 15 Feb 2017 14:45:51 -0800 (PST), mzimmers
<mzim...@gmail.com> declaimed the following:

>Heh...OK, I think I got it right this time. The BBB now boots up without
>the SD card. I'm now running Debian 8.7, which was the goal, so I can end
>this thread.
>
>Thanks to everyone who helped on this. I'm not really experienced with the
>Google groups; do I do something to mark this as answered or solved or
>anything?

        Google Groups may be echoing this, but it is not necessarily a Google
group... I'm accessing via gmane.comp.hardware.beagleboard.user -- using
the gmane NNTP (netnews) server.

Sorry buddy, you've got it backwards.

[William Hermans]

On Wed, Feb 15, 2017 at 3:45 PM, mzimmers <mzim...@gmail.com> wrote:

Heh...OK, I think I got it right this time. The BBB now boots up without the SD card. I'm now running Debian 8.7, which was the goal, so I can end this thread. 

Thanks to everyone who helped on this. I'm not really experienced with the Google groups; do I do something to mark this as answered or solved or anything?

You know, I do not know. These posts come directly to me via email from the beagleboard.org google group. I subscribed 4-5 years ago, and since I've heard talk of web "forum" like front ends for the group groups here. But I've never used one. I wouldn't think it important . . .

[mzimmers]

Hi, William - actually, I do have another question: what terminal app do you use for connecting to the BBB's serial port? I'm trying to use PuTTY, but I don't know the correct port name/number. Molloy's book uses /dev/ttyUSB0, but I don't have any such devices in my etc directory.

Thank you.

[Robert Nelson]

/dev/ttyUSB0 is the linux node name.

on mac this would be /dev/cu.usbserial

on windows, one of the COMX's..

on windows just use tera term:

https://ttssh2.osdn.jp/index.html.en

[mzimmers]

I've actually got PuTTY working under Windows 7, but not (yet) under Debian.

Here are my PuTTY settings on Debian:

Serial line: /dev/ttyUSB0

Speed: 115200

Connection type: Serial

I've saved these settings in a session, and load the session. When I try to open, however, I get the following error message:

"Unable to open connection to 192.168.0.10. Unable to open serial port."

The cable is plugged into a port that under windows is known as COM4. Might it be known by another name?

Also, I realize this discussion is off the original topic, so I'll be happy to open a new thread if anyone thinks it's worth it.

Thanks for the help.

[Robert Nelson]

On Thu, Feb 16, 2017 at 12:10 PM, mzimmers <mzim...@gmail.com> wrote:
> I've actually got PuTTY working under Windows 7, but not (yet) under Debian.
>
> Here are my PuTTY settings on Debian:
>
> Serial line: /dev/ttyUSB0
> Speed: 115200
> Connection type: Serial
>
> I've saved these settings in a session, and load the session. When I try to
> open, however, I get the following error message:
>
> "Unable to open connection to 192.168.0.10. Unable to open serial port."
>
> The cable is plugged into a port that under windows is known as COM4. Might
> it be known by another name?

Well, you could look under /dev/ttyU*....

the gtkterm package works pretty good under debian..

[William Hermans]

On Thu, Feb 16, 2017 at 9:55 AM, mzimmers <mzim...@gmail.com> wrote:

Hi, William - actually, I do have another question: what terminal app do you use for connecting to the BBB's serial port? I'm trying to use PuTTY, but I don't know the correct port name/number. Molloy's book uses /dev/ttyUSB0, but I don't have any such devices in my etc directory.

Thank you.

For serial, and ethernet I prefer puTTY.

For serial you need to go into device manager and see which COM port windows has assigned to your serial device. On Windows 8.1. . .

1) Right click "ThisPC" and select properties

2) Top( ish ) left, click device manager

3) Scroll down to Ports( COM & LPT ), expand it.

4) Look for your serial converter adapter.

At this point depending on your hardware the COM port # will be a part of the device name, or you may need to go into the device properties to find out. While you're in properties though, you may want to look at the device speed settings and all that. Here, on Windows 8.1, I have the wrong settings in here for the baud rate, and it works fine. Mines set to 9600bps

Then on to puTTY:

Once opened

1) Serial Line field needs to reflect the correct COM port for your device.

2) The Speed field needs to be: 115200

3) Connection type needs tobe set to "serial" ( radial button )

Then it should just work.

For ssh I typically ssh in from a Linux support system specifically for beaglebones. As it's as simple as:

$ ssh debian@beglebone

<enter passwd>

And I'm done. I do ssh into that support system from Windows, but there are so many guides for using puTTY, and ssh from Windows, you really don't need me to explain that.

[mzimmers]

Hi William - I'm not sure I understand...are you saying that you don't use PuTTY from a Debian host? I've got PuTTY working from Windows, but not from Debian. I think, though, it might be some kind of permission problem on the serial device. I have /dev/ttyS[0-3], but I'm not sure which one it is. From Windows, it's COM4, so I'm thinking ttyS3.

I'm wondering whether I should fool with the permissions on those, though I did try it from root, and got a similar error:

Unable to open connection to /dev/ttyS0 (or 3).

Unable to configure serial port.

  

I used gtkterm and the results were more or less the same. Not sure what I might be doing wrong here, unless it is something to do with permissions. 

[William Hermans]

Why would you want to use putty on Linux ? Literally it is as simple as ssh user@host. Where user is the username you wish to use once ssh'd into the remote system. Where host is the host address for the remote system. You can run this command like you would any other command. From a Linux terminal.

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[William Hermans]

Well, actually the remote host *MUST* have an ssh server running. But in the case of the beaglebone, it already does. You may also have to install an ssh client on the client system. But typically all but the most slim Linux installs usually have ssh client packaged in already.

[mzimmers]

But what do I do for seeing console messages? Terminal doesn't show me those.

[William Hermans]

You can use screen,, minicom, or even cat on the serial device. e.g. screen /dev/ttyUSB0 115200 - Or something like that. However, in this case It probably is better to use puTTY. As all the utilities I mentioned above have issues with line endings, and eventually will stop breaking on a linefeed - correctly.

You'd be best off googling for how to setup puTTY on Linux. Or, only use serial debug from a Windows system. The later is what I do, only use serial debug from a Windows system with puTTY. However, form the sound of it. It seems as though you have not setup permissions for the serial device yet, Typically this would probably be set to owner root:dialout. Where your user would also be a part of the dialout group. Anyway, this is another case where you'd have to google how to properly set this up. As it's not something I do, or ever plan on doing- personally.

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[mzimmers]

Before I do anything, it would seem to make sense to find out the name of the device on my Debian desktop. As I mentioned, I have /dev/ttyS[0-3]. Is there some way to determine which of these is the one I plugged the serial cable into?

On Thursday, February 16, 2017 at 1:00:21 PM UTC-7, William Hermans wrote:

You can use screen,, minicom, or even cat on the serial device. e.g. screen /dev/ttyUSB0 115200 - Or something like that. However, in this case It probably is better to use puTTY. As all the utilities I mentioned above have issues with line endings, and eventually will stop breaking on a linefeed - correctly.

You'd be best off googling for how to setup puTTY on Linux. Or, only use serial debug from a Windows system. The later is what I do, only use serial debug from a Windows system with puTTY. However, form the sound of it. It seems as though you have not setup permissions for the serial device yet, Typically this would probably be set to owner root:dialout. Where your user would also be a part of the dialout group. Anyway, this is another case where you'd have to google how to properly set this up. As it's not something I do, or ever plan on doing- personally.

On Thu, Feb 16, 2017 at 12:53 PM, mzimmers <mzim...@gmail.com> wrote:

But what do I do for seeing console messages? Terminal doesn't show me those.

On Thursday, February 16, 2017 at 12:51:20 PM UTC-7, William Hermans wrote:

Well, actually the remote host *MUST* have an ssh server running. But in the case of the beaglebone, it already does. You may also have to install an ssh client on the client system. But typically all but the most slim Linux installs usually have ssh client packaged in already.

On Thu, Feb 16, 2017 at 12:49 PM, William Hermans <yyr...@gmail.com> wrote:

Why would you want to use putty on Linux ? Literally it is as simple as ssh user@host. Where user is the username you wish to use once ssh'd into the remote system. Where host is the host address for the remote system. You can run this command like you would any other command. From a Linux terminal.

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[William Hermans]

On Thu, Feb 16, 2017 at 1:20 PM, mzimmers <mzim...@gmail.com> wrote:

Before I do anything, it would seem to make sense to find out the name of the device on my Debian desktop. As I mentioned, I have /dev/ttyS[0-3]. Is there some way to determine which of these is the one I plugged the serial cable into?

There are a few ways. But probably the most expedient way would be to tail dmesg, like so:

$ dmesg | tail

There is a way to get tail to "loop" so it stays running while you hotplug devices,, etc, but I do not recall what the command switch is off hand. Maybe -f, I'm not sure. Anyway, here is the point. run the command above without the device plugged in. Plus the device in, then run the command again, and see what's changed. It should say something about the mrusb blah blah, then givesome information on your USB device.

Another way, would be to ls in the dev directory, and look at all the tty entries. What you'll be looking for is ttyUSB, or ttyACM. Typically, what you're looking for will stand out, and if you only have one serial adapter connected, you'll only see one like it.

There are other ways too, which are too complicated to get into. But sometimes you can find information about your device by looking through the /sys sysfs file structure. For this case, that should not be necessary.

[mzimmers]

Thanks, William. I'm still having problems, so I'm going to take this to a new thread.

mz

[Dennis Lee Bieber]

On Thu, 16 Feb 2017 10:10:30 -0800 (PST), mzimmers
<mzim...@gmail.com> declaimed the following:

>I've actually got PuTTY working under Windows 7, but not (yet) under Debian.
>
>Here are my PuTTY settings on Debian:
>
>Serial line: /dev/ttyUSB0
>Speed: 115200
>Connection type: Serial
>
>I've saved these settings in a session, and load the session. When I try to
>open, however, I get the following error message:
>
>"Unable to open connection to 192.168.0.10. Unable to open serial port."

Uhm... I thought the USB serial connection was on 192.168.7.2

Well, actually, that is the virtual Ethernet on the normal USB. Which
isn't a normal serial UART.

Now, if you mean a USB-serial adapter on the /debug/ pins... I don't
think that would have an IP number, so why are you getting the 192.168.0.10
request? Are you trying to SSH on that port?

[mzimmers]

Hi, Dennis - 

PuTTY was acting a little weird...I deleted my session file and created a new one, so I'm no longer getting the error message with an IP address. So, I think we can disregard that (unless it returns).

IIRC, 192.168.0.10 was the address that I assigned to the BBB very early on. I believe I changed it because my router netmask (255.255.255.0) wouldn't accept the 7 in the third position.