As far as I know there isn't a software solution for this. The uC is not really functioning so the WDT will not kick in an reset. The problem is worse if you have large value electrolytic caps. They take a long time to discharge. Best way is to use a device which resets the uC if the voltage goes out of certain tolerance. I have used TPS79733 with good results. It has a open drain PG (power good signal). You can connect it to RST\ pin of the uC (with a pull up resistor to Vcc)
-Sumukh --- Tom Russell <tcruss...@mail.com> wrote: > have a circuit with the MSP430F133 that needs > brown-out reset. If the > power is disconnected for a short time, but not long > enough for the voltage > to decay to near-zero, I don't get a POR when power > returns and the program > goes to an unknown state. I could monitor the > voltage and when it gets low > generate a POR by pulling RST low or a PUC by > writing an exception to the > WDT. The problem is that the unit will then > continue to operate from that > point until the voltage falls low enough to mess it > up and then I still > don't think I can be sure what happens when power is > restored. I don't > think using the comparator helps because its control > register will also > become undefined as the voltage drops. > > Of course I can add an external voltage comparator > connected to the reset > pin, but anyone have a software solution? I know > some MSP parts have BOR > (brown-out reset), but strangely not all. > > Thanks for any suggestions, > > Tom Russell > > > > > ------------------------------------------------------- > This SF.net email is sponsored by: VM Ware > With VMware you can run multiple operating systems > on a single machine. > WITHOUT REBOOTING! Mix Linux / Windows / Novell > virtual machines > at the same time. Free trial click > here:http://www.vmware.com/wl/offer/358/0 > _______________________________________________ > Mspgcc-users mailing list > Mspgcc-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/mspgcc-users __________________________________ Do you Yahoo!? Yahoo! SiteBuilder - Free, easy-to-use web site design software http://sitebuilder.yahoo.com
