As I said, P1-Pin-1 and the microUSB connector power are two different inputs to two different power supplies. Having power on both of them is not a problem, and in fact, will prevent the problem of instability I was concerned about.
So, no problem powering both. The concern with the random crashes is just that, it could take three days, or could happen in the first hour. I would power the unit from both pins, if it is doing something at all important. Of course, my crashing experience is from 18 months ago, and there have been a lot of software releases since then. I would encourage you to run some endurance tests on your board, before putting it in service. --- Graham == On Fri, Aug 9, 2019 at 8:34 PM Robert Heller <[email protected]> wrote: > At Fri, 9 Aug 2019 16:23:26 -0700 (PDT) [email protected] > wrote: > > > > > > > > > Robert: > > > > It has been a while, almost a year since I did any testing with the > > PocketBeagle. > > But I don't think anything has changed relative to my comments below. > > Maybe someone can correct me if I am wrong, and some things have been > fixed. > > > > P1-Pin-1 is Vin, and is equivalent to the Barrel Jack input on the > > Beaglebone Black, it > > is a separate power supply input, and is isolated from the microUSB > > connector power. > > > > P1-Pin-7 is hardwired to the +5 pin on the microUSB connector, USB Port > 0. > > It is not clear from the schematic, but is visible if you view the PCB > > board plots. > > Or check it with an Ohmmeter. > > > > I found that the PocketBeagle, when powered exclusively by P1-Pin-1 > would > > randomly > > crash about once every 24 hours of operation, without any apparent > reason, > > or > > any clue in the logs. I hope that this has been fixed, but I have seen > > other reports > > since I initially reported it, and nothing since that reported a fix. > > Well, I am not expecting an application that would run 24/7. I am working > on > model RR control circuits. It does not sound like this should be an > immediate > problem. > > > > > > The only workaround I found was to power P1-Pin-1 and P1-Pin-7 in > parallel, > > in which case > > it does not crash, but now there is no isolation between USB +5V and > your > > independent > > PB power supply, and, as you are concerned about, all kinds of > cross-feed > > and back > > powering can occur. > > That does not sound like a really good idea. > > Question: if the board was powered from P1-Pin-1 *and* the USB will there > be > problems? Right now, that is my main concern. Jacking in the USB (for > file > transfer mostly, since I can use the serial console for debugging) while > the > board is being powered via P1-Pin-1 is something I'd like to be able to > do, > but don't want to fry anything. > > > > > I suggest you read the email thread "PocketBeagles are Unstable" started > > 11/24/2017 > > Will have a look. > > -- 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/CANN_KV4OqWQ05koKPk8-bLAG7yYocYVJoN7vw_NvJNuer_7JGQ%40mail.gmail.com.
