The power chip TPS65217 needs PWR_BUT P9.9 pulled low (<0.4V) for more than 50ms, but less than 8sec. It appears the DS3231 can hold its INT/SQW pin low for 1 second
On Friday, 4 September 2020 at 23:14:19 UTC+1 [email protected] wrote: > The PWR_BUT P9.9 pulled down to DGND by the DS3231 INT/SQW pin might be > the same as pressing the POWER BUTTON > > On Friday, 4 September 2020 at 22:51:05 UTC+1 [email protected] wrote: > >> That’s not quite what I am asking. I want to set the alarm in the >> DS3231, shut down the BBB, completely, then have the Alarm / INT pin on the >> DS3231 initiate a series of events that eventually powers on the BBB. >> Doing this, I can achieve a true zero power sleep state. Nothing will >> draw power except the coin cell on the DS3231. >> >> I can set the alarm in the DS3231 using python libraries, is it possible >> to set that alarm using the device drivers? I have a bunch of relay and >> delay circuits that area all working, this is the last link in the chain. >> I will use the python if necessary but would prefer to use the kernel >> drivers. >> >> I need the BBB to power up for a couple hours every two weeks and last >> for a year on a stack of D cells; the normal sleep state draws too much >> power, I want to shut it off. >> >> The reddit page I linked describes the exact same problem and solution >> for RaspPi. Is there a similar solution for BBB? >> >> Thx, >> Steve >> >> >> >> https://www.reddit.com/r/raspberry_pi/comments/bn2ht5/ds3231_rtc_using_the_alarm_function/ >> >> >> On Sep 4, 2020, at 5:40 PM, Robert Nelson <[email protected]> wrote: >> >> On Fri, Sep 4, 2020 at 3:13 PM [email protected] >> <[email protected]> wrote: >> >> >> I do not know the AM3358 of the BBB, but from the schematic >> P9.42 GPIO0_7 is XDMA_EVENT_INTR2 >> >> >> Really any GPIO_0 can be used for "wake-up" from "suspend".. >> >> >> https://e2e.ti.com/support/processors/f/791/t/243392?How-to-wake-up-the-BeagleBone >> >> >> https://processors.wiki.ti.com/index.php/AM335x_Power_Management_Standby_User%27s_Guide#GPIO_wakeup >> >> It's not trivial.. >> >> Regards, >> >> -- >> Robert Nelson >> https://rcn-ee.com/ >> >> -- >> 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/CAOCHtYjBba%2Byja4ZMqXU4u68YLvxFvveycJM5CM%2BQSmkZJmsxA%40mail.gmail.com >> . >> >> >> -- 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/4168928c-c516-466c-838f-9ff1a12804c1n%40googlegroups.com.
