Thank you for your quick reply. you wrote:
> No shutdown is a function of the SW.The SRM covers the hardware. > OK, than I suppose that somewhere in the whole Debian package, a routine is permanentely checking (polling) if 5V DC power supply is still "ON". When it is not the case an event is fired in order to start a clean shutdown procedure? Am I correct ? Does this happen via the I²C bus ? Does this routine makes a polling to the TPS65217C PMIC ? > No shutdown means you have enough battery power to keep running until > power is restored. > The battery lasts more than 6 hours in my case but is of no need 60 seconds after power "OFF" because of a self shutdown due to the actual system behaviour. I don't blame this because it prevents corrupting datas in most systems but it doesn't suit the most important requirement when monitoring systems 24h a day: it must run even during power outage like an alarm system. > You would need to add that function into your SW. > Logically, I suppose that a register is modified somewhere when power off occurs ? I don't quite understand what you mean by adding that function. This function has to be modified in order to prevent shutdown I suppose ? But where is it located ? The RasPBX (VoIP) running on BBB doesn't have this drawback but I hesitate to post a message on their forum because this issue is out of VoIP topic Configuration of this power management behaviour would be ideally perform right during OS installation like it occurs on PC within the BIOS. This battery backup feature is a major advantage over Raspberry pi but perhaps am I requesting to much from the BeagleBone Black :-). Kind regards Michel. > > Gerald > > On Thu, Oct 16, 2014 at 7:40 AM, <[email protected]> wrote: > >> Hello everybody, >> >> I am using a BeagleBone Black version A6A with Debian distribution on a >> µSD card. >> >> debian@beaglebone:~$ uname -a >> Linux beaglebone 3.8.13-bone50 #1 SMP Tue May 13 13:24:52 UTC 2014 armv7l >> GNU/Linux >> >> I want to avoid BBB shutdown during power outage. Therefore a battery >> backup is directly connected to BBB as described on the following link: >> BeagleBone >> Black UPS >> <http://www.beaglebone-asterisk.org/uninterruptible-power-supply-ups-for-beaglebone-black-a-diy-project/> >> >> Unhappily, as soon as a power outage occurs, the BBB performs a clean >> shutdown within approx. 60 seconds as battery is still connected. >> >> In fact, quite a lot of applications must still run during and after >> power outage. >> I didn't find in the BBB reference manual and documentation any tips >> related to "no shutdown" procedure. When Googling, every topic, I could >> find, is related to the way shutdown occurs. Monitoring battery level >> before shutdown procedure also exists on some forums but nothing preventing >> shutdown when a battery backup is available. I must admit that I am not >> skilled enough to handle very complicate programming tasks. Therefore >> trying to dig in source code is difficult. I only use Python for basic >> tasks. >> >> I tried Angström distribution installed on the BBB (Rev A6A) and >> encountered the same shutdown problem when removing 5V DC power supply. >> >> There is an interesting Power Cape on the market that may be configured >> for different BBB behaviours. It is certainly the best solution. But I want >> to keep budget and power consumption as low as possible. >> Last comment to avoid misunderstanding: for my application, during power >> outage, I only need 3.3V power supply...not 5V. >> Only Ethernet interface and some GPIO are used. >> >> >> Does anyone knows how to avoid this shutdown procedure? Some guidelines >> would be appreciated >> >> Kind regards >> >> Michel. >> >> >> -- >> 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]. >> 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]. > 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]. For more options, visit https://groups.google.com/d/optout.
