From: William Hermans <[email protected]> Reply-To: <[email protected]> Date: Tuesday, March 25, 2014 at 10:02 PM To: <[email protected]> Subject: Re: [beagleboard] Hardware watchdog for BBB
> Hi John, > > Yeah, the MSP430G2553 can go down to at least 1.8v, and I am thinking a good > bit lower. I am thinking perhaps 1.2V at minimal clock / periph's( I'd have to > read the datasheet again ) Now just because I am relatively new to embedded > devices, and I know the MSP430's fairly well, I would choose these for myself. > The MSP430 value line products can not beat or even meet that price by a long > shot in small quantities. I think the lowest my buddy got a tube of 10 for > ~$1.35 each a bit over a year ago. One or two off, personally I think this > price is fair enough. > > I haven't heard of the devices you're linking to, and the link doesn't work > for me. So i can not even look to see exactly what it is. I would assume the > MSP430G2553 would be overkill by comparison, feature wise. > > So, I am not much of an EE, but my buddy is. Perhaps I could get him to design > something up while I'll tie things together in software. This is something I > personally have interest in as well. Hi William, Strange, I just clicked on the link below and it works for me. Search Google for silego and greenpak. It¹s really like a miniature mixed signal FPGA. They have a really nice software tool/simulator and dev board. I use these all the time instead of using discrete logic. They are really good for small state machines with inputs from timers, counters, analog comparators, lookup tables, macrocells, etc. Regards, John > > > > On Tue, Mar 25, 2014 at 5:44 PM, John Syn <[email protected]> wrote: >> >> From: William Hermans <[email protected]> >> Reply-To: <[email protected]> >> Date: Tuesday, March 25, 2014 at 3:41 PM >> >> To: <[email protected]> >> Subject: Re: [beagleboard] Hardware watchdog for BBB >> >>> Yeah after I thought about it, after making my post I realized I did not >>> include a way to bring the BBB back up. >>> >>> For bringing the BBB back up after input power is back up I suppose I would >>> use an MSP430 to monitor the input power, and a "keep alive" signal from the >>> BBB to the MSP430. A Value line MSP430 such as the MSP430G2553 is low cost ( >>> ~$2.5 in quantities of 1 ) can run off a single button cell for years. the >>> MSP430G2553 also has SPI, I2C, GPIO's, and UART, as well as a few other >>> niceties( hardware WDT, and Timer(s).) >>> >>> So perhaps more complex than I originally led on, but perfectly doable, and >>> not really all that complex. Just off the top of my head, I would use either >>> a regular timer, or perhaps even use the hardware watchdog timer to cycle a >>> reset on the BBB through a GPIO. With the keep alive signal being sent out >>> over either SPI or UART. >>> >>> Is this on track with what you had in mind, or are you thinking of something >>> else, or is this too complex for your application ? >> Hi William, >> >> I like your solution. I used a GreenPak from http://www.silego.com/ which are >> really low cost $0.35 in small quantities. They are tiny (about 2mm square) >> and very robust; no need for WDT. Also, they work down to 1.8V, which is >> required when working with supercaps. >> >> Regards, >> John >>> >>> >>> >>> On Tue, Mar 25, 2014 at 12:50 PM, John Syn <[email protected]> wrote: >>>> >>>> From: Timbo <[email protected]> >>>> Reply-To: <[email protected]> >>>> Date: Tuesday, March 25, 2014 at 6:12 AM >>>> >>>> To: <[email protected]> >>>> Subject: Re: [beagleboard] Hardware watchdog for BBB >>>> >>>>> >>>>>> What happens when you have 10K, 100K or even 1 Million devices running. >>>>> >>>>> Now we know where all the BBBs went! >>>> Very funny. BBB wouldn¹t work for my application but I do draw from >>>> Gerald¹s brilliance ;-) >>>>> >>>>> >>>>> For home use I've rigged two BBBs together so that each can monitor and >>>>> reset the other. Every 5 minutes each board tries to send itself a >>>>> message via an ssh connection to the other board. If it fails to receive >>>>> that message, it assumes the other board has crashed somehow and sends a >>>>> reset. If it still fails to get a response it carries out a power cycle. >>>>> >>>>> In conjunction with a simple UPS such as the OP describes, this would >>>>> probably be enough for normal use. >>>>> >>>>> >>>>> -- >>>>> 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. >> -- >> 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.
