Just my 2 cents... For watchdog thing I think the ATtiny is just overkill. That kind of operation can be done with simple 555 timer or even few diodes and transistor.
Don't get me wrong. The ATtiny (15L) for example can do that job but as safety device the any micro isn't good way. And if system hang who says that it can't set wrong configuration and disable watchdog? Just do that without micro and use micro for other complicated thing.. 2010/12/4 Kirk Wallace <kwall...@wallacecompany.com> > On Sat, 2010-12-04 at 09:55 +0800, Jim Coleman wrote: > > I like the idea of a dip switch or solder bridges if one doesn't plan on > > changing the setting alot and wants to save the cost of the dip switch. > > while the pot would be easy to adjust, it's less precise than a truth > table > > of the dip/bridge positions and the resultant reset timer. > > > > Jim > > Thanks Jim. I agree that it would be nice to have a precise, stable > input, but I am also trying to avoid any hardware complexity in order to > avoid an upgrade loop (ATtiny -> ATmega -> Atom Cube -> Nanotube > Superconducting Buckyball hyper... ). It may also be that one or a few > presets might be enough. If charge pump is running at 1kHz (based on > servo thread), it may be acceptable to wait up to a hundred cycles or .1 > seconds to trip an e-stop. If this is the case, .1 seconds might cover > the range of common watchdog frequencies. Without testing or experience, > I have a hard time knowing what will work. > -- > Kirk Wallace > http://www.wallacecompany.com/machine_shop/ > http://www.wallacecompany.com/E45/index.html > California, USA > > > > ------------------------------------------------------------------------------ > What happens now with your Lotus Notes apps - do you make another costly > upgrade, or settle for being marooned without product support? Time to move > off Lotus Notes and onto the cloud with Force.com, apps are easier to > build, > use, and manage than apps on traditional platforms. Sign up for the Lotus > Notes Migration Kit to learn more. http://p.sf.net/sfu/salesforce-d2d > _______________________________________________ > Emc-users mailing list > Emc-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/emc-users > ------------------------------------------------------------------------------ What happens now with your Lotus Notes apps - do you make another costly upgrade, or settle for being marooned without product support? Time to move off Lotus Notes and onto the cloud with Force.com, apps are easier to build, use, and manage than apps on traditional platforms. Sign up for the Lotus Notes Migration Kit to learn more. http://p.sf.net/sfu/salesforce-d2d _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users