In my case I have a cape that connects via USB (besides the usual headers). 
And I have a TP on VBUS, sometimes just inserting a tester on the test 
point generates a Babble Interrupt.

Mine isn't properly grounded.

You can always check the governor and cpu frequency with:

juanjo@balin:~$ cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor
ondemand
juanjo@balin:~$ cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_cur_freq
300000

On Monday, November 4, 2013 12:12:53 PM UTC-3, Philippe Laurent wrote:
>
> A few more updates. I've read in a number of other locations that this 
> might be due to a grounding issue or a power draw issue. Starting with 
> tackling the power draw issue, it appears that the system bus outputs 
> different power to the USB device depending on its CPU throttling status. 
> The lower the CPU speed, the (slightly) lower the USB output.
>
> Still using Ubuntu 13.04, I've removed both the S99ondemand startup script 
> from the rc2.d folder, as well as placed the line "
>
> echo 'on' | tee /sys/bus/usb/devices/usb1/power/control" in the 
> /etc/rc.local script (no quotes) to try and mitigate the issue. The former, 
> from what I understand, keeps the CPU running at full speed, and does not 
> let it slow down based on demand, the latter works to keep USB power on to 
> the port at all times, rather than letting the BBB decide whether to power 
> it off/on.
>
> At this point, the BBB has not thrown any more Babble errors through 
> multiple power off/on events, nor through any extensive scanning or quiet 
> time.
>
> Of note, there may also be some merit in the grounding issue, as walking 
> across the floor and then touching the BBB case will occasionally cause the 
> Babble issue to appear and the Symbol device to power off. The device is 
> connected to a DC power supply, but there is no grounding plug with the 
> brick, so it stands to reason that the device is not grounded.
>
> Hope this helps someone... although I'm sure that at this point I have no 
> concrete solutions to the problem.
>
> On Saturday, November 2, 2013 12:32:03 PM UTC-4, Philippe Laurent wrote:
>>
>> Crap. On third reboot (full power off/on), the device is experiencing 
>> the same musb: Babble Interrupt error as before.
>>
>> So... this is a hardware issue? The BBB is powered by a separate adapter 
>> (not USB), so power shouldn't be the problem.
>>
>> On Friday, November 1, 2013 1:13:09 PM UTC-4, Philippe Laurent wrote:
>>>
>>> I resolved my issue by installing and using Ubuntu 13.04 on the BBB. 
>>> It's been up and running the python scanning script for over 24 hours, 
>>> which is roughly 23 hours longer than it has before. I used the 
>>> instructions at 
>>> http://shrkey.com/setting-up-beaglebone-black-to-boot-off-the-microsd-card/to
>>>  get the installation squared away.
>>>
>>> On Wednesday, October 30, 2013 9:51:30 AM UTC-4, Bekir Bahadir wrote:
>>>>
>>>> Same problem here. Im also willing to pay for a solution
>>>>
>>>> Am Samstag, 31. August 2013 17:42:09 UTC+2 schrieb [email protected]:
>>>>>
>>>>> I'm using my Beaglebone Black with a USB temperature sensor. It works 
>>>>> very well, however I noticed monitoring stopped last night after roughly 
>>>>> 35 
>>>>> days uptime. This morning I looked more closely into the log file and 
>>>>> noticed:
>>>>>
>>>>> kernel: [2892926.929555] CAUTION: musb: Babble Interrupt Occurred
>>>>>
>>>>> I wasn't able to successfully reset the USB device and before I was 
>>>>> able to restart the BBB stopped responding. I power-cycled it and it was 
>>>>> back to normal again. Any ideas what caused this kernel message?
>>>>>
>>>>

-- 
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 [email protected].
For more options, visit https://groups.google.com/groups/opt_out.

Reply via email to