beaglebone suddenly died

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1

I removed the power plug from my beaglebone black at the same time I did a reboot (in retrospect somewhat reckless) and when I power on the device the four user LEDs are all black and the beaglebone doesn’t present itself as a USB device anymore.

Is there anything that can be done to salvage the device?

2

You can go to the support WIKI, the address on the white card in the box, and restore the eMMC by reflashing it.

Gerald

3

Thank you, it seems to have worked perfectly =)

4

Is this a usual phenomenon in the BeagleBone ?? or just a rare occurrence ?

thanks
a

5

It happens every now and then. It is not known the cause for all of them. A lot of them is improper voltage sequencing on the I/O pins.

Gerald

6

this can happen to any device that has cached writes to a disk drive. If the writing process is interrupted during writes to important areas then a device can suddenly die. You can avoid it by splitting the roof file system into a few partitions with setting very important ones to a read-only mode.

7

Is this a real solution? Do the partition tools make sure that no two partitions share data on any of the physical, and large, erase blocks? Otherwise, physical disk writes would still occur even for read only data.

8

I am thinking if this was related to improper shutdown, then maybe I could add a large capacitor or a battery to prevent power glitches or sudden power failures.

I could even add an external power supervisor that monitors the power and prevents such glitches.

What do you mean by ‘improper voltage sequencing’ ??

thanks
a

9

An external supervisor is not required. Adding a battery to the battery connector to keep thing up for a few of second is all that is needed. As soon as power is removed from the PMIC, it will switch to battery and send an interrupt to the processor so it can start the shutdown process.

I guess you have not read the processor datasheet. You have to turn voltage on in a specific order. Any pin that is exposed to a voltage out of the proper sequence is subject to damage. For example. If you have 3.3V on an I/O pin immediately after power is applied, instead of when the 3.3V rail has been turned on, you can pop the pin. Take a look at the TPS65217C datasheet. It has charts and tables showing this function.

Gerald