HELP! - I can't access my BBB any more.

[Roman Prilutsky]

My BBB was running debian jessie and i could access it over USB  and Ethernet. Then, after one power off/power on it stopped booting from eMMC. To be exact I stoped been able too access it over both USB and Ethernet.  I can still boot the board from SD and access the bard.  eMMC boot though seems never finishes. I can see leds blinking in a normal boot sequence and then they end up with one led blinking for ever. 

If i boot from SD i can access eMMC file system (rootfs) and my /etc/network/interface on eMMC looks normal. I do not know of any other way to read a boot log on eMMC or anything to help me to understand the issue.

Of course i could re-flash eMMC but then i will never know what happen :( Any help/ideas are greatly appreciated. Thanks!    

[evilwulfie]

when you shutdown your bone did you just pull the plug or use the shutdown now -h command then remove power ?

--
For more options, visit http://beagleboard.org/discuss
---
You received this message because you are subscribed to the Google Groups "BeagleBoard" group.
To unsubscribe from this group and stop receiving emails from it, send an email to beagleboard...@googlegroups.com.
To view this discussion on the web visit https://groups.google.com/d/msgid/beagleboard/062d34cc-7c92-44e3-a609-b27c9cf991a0%40googlegroups.com.
For more options, visit https://groups.google.com/d/optout.

[Roman Prilutsky]

No. I am developing some software to run as a part of an automation project, so expect the board to be tolerant to the power loss. So i just pulled the pug out - no shutdown -h. 

What could break and what is a way to diagnose it?

[Robert Nelson]

On Wed, Feb 8, 2017 at 1:22 PM, Roman Prilutsky
<romanpr...@gmail.com> wrote:
> No. I am developing some software to run as a part of an automation project,
> so expect the board to be tolerant to the power loss. So i just pulled the
> pug out - no shutdown -h.
> What could break and what is a way to diagnose it?

"expect", well the board isn't designed for that application...

If your just going to yank power with the BBB, "expect" both software
and hardware failures* (documented in the SRM)..

Regards,

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

[evilwulfie]

If you want a board that can be unplugged with no damage better look elsewhere.
Or do what i have done and design around that limitation.

--
For more options, visit http://beagleboard.org/discuss
---
You received this message because you are subscribed to the Google Groups "BeagleBoard" group.
To unsubscribe from this group and stop receiving emails from it, send an email to beagleboard...@googlegroups.com.

To view this discussion on the web visit https://groups.google.com/d/msgid/beagleboard/c1e88630-ebf7-427b-8943-564bd650bbf9%40googlegroups.com.

[Roman Prilutsky]

On Wednesday, February 8, 2017 at 7:34:08 AM UTC-5, Roman Prilutsky wrote:

Thanks Wulf Man. What exactly have you done to avoid this limitation? I'd love to do the same.

[evilwulfie]

ME and a software buddy have a nice watchdog timer powered from the BBB battery holds up the BBB till it shuts down then removes power
draws 400uA from the battery while waiting for the power to be reapplied.

--

For more options, visit http://beagleboard.org/discuss
---
You received this message because you are subscribed to the Google Groups "BeagleBoard" group.
To unsubscribe from this group and stop receiving emails from it, send an email to beagleboard...@googlegroups.com.

To view this discussion on the web visit https://groups.google.com/d/msgid/beagleboard/9c4640af-759f-4f8a-bba8-6ded717dca0a%40googlegroups.com.

[William Hermans]

On Wed, Feb 8, 2017 at 3:16 PM, evilwulfie <evilw...@gmail.com> wrote:

ME and a software buddy have a nice watchdog timer powered from the BBB battery holds up the BBB till it shuts down then removes power
draws 400uA from the battery while waiting for the power to be reapplied.

So, in a pinch, and if you have  physical access to the board. You can use a LiPO battery, connected to the PMIC battery test points( ask an EE if you need specifics ), then install the debian package acpid. Then everything should be fine. e.g. the board will power down cleanly. However, the PMIC will still be supplying a bit of power from the battery. So if you need it shutdown for an extended time period. You'll need to disconnect the battery.

As for remotely installed systems. You'll have to design a watchdog / power management system to disconnect the battery, and reset the processor when power is reapplied. This is why in Jason's post yesterday, or the day before. I mentioned I like to see a proper UPS cape with good power management features built in. The beaglebone as it is is what I'd consider a very good board, but to cut costs, when designed. Several things were left out of the board. So instead of paying $100 + per board, we pay ~$50 per board, and design in features we need for our own situations. A fair trade, but something we need to be aware of.