I have some questions: 1) What happens if the internal watchdog does not allow for a long timeout? 2) When developers create the system and want a HW watchdog, what in the OS tickles the watchdog? Is that done by the sanity task or is it done by the OS in some other manner (os time tick, for example)? Or does the creator of the application need to provide for the tickle?
Thanks PS I am not sure if memory serves (and it rarely does!) but I think I have worked on older MCU’s whose maximum internal watchdog timeout was < 1 second. I dont know if current day MCU’s have this kind of limitation, but if they did, how would that be addressed? Or is it not a concern... > On Aug 29, 2016, at 4:40 PM, marko kiiskila <[email protected]> wrote: > > Hi, > > I was going to add support for hardware watchdog(s). > The API I was thinking would be pretty simple. > > The first user for this would be the sanity task. > > —8<--- > /* > * Set the watchdog time to fire no sooner than 'expire_secs' seconds from now. > */ > int hal_watchdog_init(int expire_secs); > > /* > * Tickles the watchdog. Needs to be done before 'expire_secs' fires. > */ > int hal_watchdog_tickle(void); > > /* > * Stops the watchdog. > */ > int hal_watchdog_stop(void); > > —8<——— > > Let me know if this doesn’t seem right.
