If having a battery in the device makes some of you queasy, you could always put it outside, on the back. But I seriously believe there are ways to make battery backup which will not leak.
D. On 27 Feb 2014 06:52, "Chuck Harris" <cfhar...@erols.com> wrote: > That fix presumes that the power line never quits at > inappropriate times. This winter has provided me with > ample reminders that power can go out anytime. > > I think a better solution would be to find a very large > "super cap" and power the BBB from that while giving it > a power fail interrupt to quickly sync the file system. > > -Chuck Harris > > John Seamons wrote: > >> On Feb 25, 2014, at 12:59 PM, John Seamons <j...@jks.com> wrote: >> >> I may have a solution for the power-off problem that doesn't involve >>> batteries >>> or supercaps. It has the added advantage of providing instant-on. >>> >> >> From the latest documentation: >>> >> >> "One solution to the annoyance of having to halt the BBB before the >> instrument is >> powered off is simply to keep the BBB running by providing it a secondary >> source >> of power via the USB-mini port. The BBB already understands how to select >> between >> two sources of power: the USB-mini and +5V barrel connectors (the latter >> of which >> is actually being delivered from the 5370 via the board expansion >> connectors). The >> app detects when the instrument has powered down and resumes running when >> power is >> restored. USB power could come from an external USB hub or charger. You >> may have >> to obtain a longer USB cable than the one supplied. Be certain to only >> use the >> USB-mini connector that is adjacent to the Ethernet RJ45 connector. Do >> not use the >> USB-A connector on the other end of the board as that port will not >> accept input >> power. >> >> Some of you might even figure out how to derive +5V for the USB-mini >> cable from >> the 5370 oven power supply card that is always powered if the instrument >> is off >> but the line cord is plugged in. But beware of the potential problem of >> conducting >> noise from the BBB to the reference oscillator over such a connection. >> Some >> experimentation and measurement is necessary. The planned USB/Ethernet >> connector >> card that replaces the current HPIB one at the back-panel could host a >> voltage >> regulator. Aligator clip connections to the '+25V UNREG' and GND test >> points on >> the oven power supply would alleviate the need for any soldering." >> >> _______________________________________________ time-nuts mailing list -- >> time-nuts@febo.com To unsubscribe, go to >> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the >> instructions there. >> >> _______________________________________________ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/ > mailman/listinfo/time-nuts > and follow the instructions there. > _______________________________________________ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.