I don't know of anyone I could recommend, but I would think that others in the community would have something like this.
Gerald On Thu, Sep 25, 2014 at 5:52 PM, <mojokor...@gmail.com> wrote: > Yes, we do have brown outs and are putting UPS on the system to avoid > this, so that should take care of it for now. > > One other thing that we've been concerned about for a while is that > immediate shutdown could cause a problem if it interrupts a MySQL operation > or even a filesystem operation. > > It would great to have a power down detection cape with a super cap that > keeps the board running for 30 seconds and triggers an input/interrupt that > shuts down the system using the OS command. I plan to contact some cape > makers to see if there's interest in creating such a cape. Any suggestions > for who to contact? > > > > On Thursday, September 25, 2014 9:17:42 AM UTC-7, Gerald wrote: >> >> We are looking at the idea that maybe the PMIC gets confused when there >> is a power dip on power up, basically a power supply that can't handle >> the surge when the board powers up. The idea is the PMIC >> starts shutting down and then tries to power up again when the dip goes >> away. I have yet to capture this myself, but there is one person he says he >> sees this on his board. >> >> If you have power than can brown out for a short period of time, this >> could be your issue based on this idea we are looking out. You might try >> adding a battery to the battery lead or maybe a super cap that can at least >> stop the shutdown from starting when it thinks the 5V is going away.. >> >> Gerald >> >> On Thu, Sep 25, 2014 at 10:49 AM, <mojok...@gmail.com> wrote: >> >>> Thanks for your fast reply. >>> >>> I've seen it on two of our boards - out of about 15. Only one of them >>> had a cape (the RTC cape). Any idea if that one causes the issue? >>> >>> I admit that the boards are installed over in Africa where clean AC >>> power sources are not common. We are putting a UPS on the system to clean >>> up spikes and avoid brown outs. >>> >>> One question... >>> >>> Does powering down a unit via unplugging a supply from the AC (the wall) >>> also constitute a "violent" interruption in power, or is it just unplugging >>> the power connectors from the board? >>> >>> >>> >>> On Wednesday, September 24, 2014 1:33:52 PM UTC-7, Gerald wrote: >>>> >>>> It is still an issue. We have seen it on .003% of the boards shipped. >>>> The issue can also be related to improper design of capes that violate the >>>> power up sequence. It may be a while before that shows up as a failure. >>>> >>>> Gerald >>>> >>>> >>>> On Wed, Sep 24, 2014 at 3:05 PM, <mojok...@gmail.com> wrote: >>>> >>>>> Hello, >>>>> >>>>> I saw the following on the Beagle Bone wiki page... >>>>> >>>>> "Improper Power Down....All Revisions >>>>> >>>>> ... Based on the latest information we have gathered, this appears to >>>>> be an instance where the PMIC does not power down the processor in the >>>>> right order due to the violent removal of the power cables, either USB or >>>>> DC. So, we are recommending that the power button be used to power off the >>>>> board or by issuing the Halt command. After that you can remove the power >>>>> cable. If everyone follows this process, we should see a decrease in these >>>>> issues, but it will take a while for the results, either good or bad, to >>>>> show up. This will also help prevent the contamination of the eMMC and the >>>>> SD cards by allowing the kernel to shutdown properly before power is >>>>> removed." >>>>> >>>>> >>>>> I also saw in one post that Gerald noted this was thought to be an >>>>> issue, but now has been dismissed. >>>>> >>>>> >>>>> Can you confirm that this is still an issue or not. >>>>> >>>>> >>>>> The reason that I ask is that we are having Beagle Bone Black failures >>>>> in the field where they go dead and we are trying to nail down why. >>>>> >>>>> >>>>> If this is still an issue would unplugging a power supply from the >>>>> wall be considered "violent" removal of the power? >>>>> >>>>> >>>>> Thanks, >>>>> >>>>> >>>>> Jeremy >>>>> >>>>> -- >>>>> 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. >>>>> For more options, visit https://groups.google.com/d/optout. >>>>> >>>> >>>> -- >>> 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. >>> For more options, visit https://groups.google.com/d/optout. >>> >> >> -- > 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+unsubscr...@googlegroups.com. > For more options, visit https://groups.google.com/d/optout. > -- For more options, visit http://beagleboard.org/discuss --- You received this message because you are subscribed to the Google Groups "BeagleBoard" group. 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