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. On Tue, Mar 25, 2014 at 5:44 PM, John Syn <john3...@gmail.com> wrote: > > From: William Hermans <yyrk...@gmail.com> > Reply-To: <beagleboard@googlegroups.com> > Date: Tuesday, March 25, 2014 at 3:41 PM > > To: <beagleboard@googlegroups.com> > 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 <john3...@gmail.com> wrote: > >> >> From: Timbo <tim...@gmail.com> >> Reply-To: <beagleboard@googlegroups.com> >> Date: Tuesday, March 25, 2014 at 6:12 AM >> >> To: <beagleboard@googlegroups.com> >> 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 wouldn't work for my application but I do draw from >> Gerald's 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 beagleboard+unsubscr...@googlegroups.com. >> 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 beagleboard+unsubscr...@googlegroups.com. >> 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 beagleboard+unsubscr...@googlegroups.com. > 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 beagleboard+unsubscr...@googlegroups.com. > 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 beagleboard+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
