> > *Use a super capacitor.* > Ok, a little abstract . . .
Use a super capacitor, and if using a console image . . . sudo apt-get install acpid Then the board will automatically shutdown when 5V input goes missing. I'd make sure you pick a super cap that can sustain the beaglebone for ~30 seconds, even if not needed. Just in case. Typically though, here, we see that the board shuts down within 5 seconds or so. Maybe slightly longer. On Mon, May 2, 2016 at 10:47 AM, William Hermans <[email protected]> wrote: > *I have been building embedded systems for a while now and I am >> considering using the beaglebone (BBB) for an upcoming project, but I am >> confused by everything I read regarding the shutdown requirements. As an >> embedded system the only way to turn it off is to simply shutdown the power >> with a switch, yet my preliminary research indicates that this is a no-no >> as it may damage the BBB and/or corrupt the file system. I also read a lot >> of comments regarding voltage on the pins after a shutdown; in my case, >> very likely there will be a CAT5 cable with live activity connected even >> after power down; assume the magnetics should protect the BBB, but just >> checking.* >> > > This is true of any system running an OS that is not red only. If you > unceremoniously yank the power, you're asking for trouble. > > *I have used quite a few micro controllers and various self-standing >> systems, but am fairly new to the BBB - still mostly reading about it. Am >> I missing something? How can a device meant to be used in embedded systems >> not be tolerant of power loss and be so finicky about power?* >> > > It sounds like you're missing a lot. It sounds like you've had a lot of > experience with small micros, that run bare metal, but have have no, or > limited experience with using an embedded OS. > > Then if you stop and think of the cost of this board, and what the goal of > beagleboard.org was when the board was created. Perhaps then it become > clear as to how / why we're where we are in this context. You can fix all > of this yourself, using external hardware, and custom software. > >> >> *By the way, I can see there is a battery backup circuit but I do not >> want to use a lithium battery for safety/temperature/cost reasons. Using a >> large capacitor also seems tricky as the shutdown may take a few seconds so >> I don't see how that will work.* >> >> *Any suggestions would be greatly appreciated.* > > > Use a super capacitor. > > > > On Mon, May 2, 2016 at 8:39 AM, Gerald Coley <[email protected]> > wrote: > >> >> >> On Mon, May 2, 2016 at 10:36 AM, Yiannis Papelis <[email protected]> >> wrote: >> >>> I have been building embedded systems for a while now and I am >>> considering using the beaglebone (BBB) for an upcoming project, but I am >>> confused by everything I read regarding the shutdown requirements. As an >>> embedded system the only way to turn it off is to simply shutdown the power >>> with a switch, yet my preliminary research indicates that this is a no-no >>> as it may damage the BBB and/or corrupt the file system. I also read a lot >>> of comments regarding voltage on the pins after a shutdown; in my case, >>> very likely there will be a CAT5 cable with live activity connected even >>> after power down; assume the magnetics should protect the BBB, but just >>> checking. >>> >>> I have used quite a few micro controllers and various self-standing >>> systems, but am fairly new to the BBB - still mostly reading about it. Am >>> I missing something? How can a device meant to be used in embedded systems >>> not be tolerant of power loss and be so finicky about power? >>> >>> By the way, I can see there is a battery backup circuit but I do not >>> want to use a lithium battery for safety/temperature/cost reasons. Using a >>> large capacitor also seems tricky as the shutdown may take a few seconds so >>> I don't see how that will work. >>> >>> Any suggestions would be greatly appreciated. >>> >>> -- >>> 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]. >>> To view this discussion on the web visit >>> https://groups.google.com/d/msgid/beagleboard/4b2dc307-631d-405d-88d6-7537adb3ac29%40googlegroups.com >>> <https://groups.google.com/d/msgid/beagleboard/4b2dc307-631d-405d-88d6-7537adb3ac29%40googlegroups.com?utm_medium=email&utm_source=footer> >>> . >>> For more options, visit https://groups.google.com/d/optout. >>> >> >> >> Main reason for the shutdown process is the corruption of the Linux file >> system. >> >> If you have power on any signal when the processor is shutdown, then you >> are asking for trouble. >> >> >> http://www.elinux.org/Beagleboard:BeagleBoneBlack#Expansion_Header_Pin_Usage >> >> >> Gerald >> >> [email protected] >> http://beagleboard.org/ >> [email protected] >> >> -- >> 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]. >> To view this discussion on the web visit >> https://groups.google.com/d/msgid/beagleboard/CAHK_S%2BergZ8%2BPd5zBdxsHqJDzQphgPXKXF0oayzjV1PVHPY8kw%40mail.gmail.com >> <https://groups.google.com/d/msgid/beagleboard/CAHK_S%2BergZ8%2BPd5zBdxsHqJDzQphgPXKXF0oayzjV1PVHPY8kw%40mail.gmail.com?utm_medium=email&utm_source=footer> >> . >> >> 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 [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/beagleboard/CALHSORqqALRuwazqWtdLK4uzTKe8EJShCx60943s3%3DuvWBrroQ%40mail.gmail.com. For more options, visit https://groups.google.com/d/optout.
