[SI-LIST] Re: Reset problem with power supply

> I am going to make it robust by making the small micro controller ( we
> could have used a small CPLD for that matter) act as watch dog. If it
> does not get a signal from the main processor for a specified time, it
> will generate a reset. 

What resets that micro?

If I was chasing this problem, I'd get out the data sheet on each major chip 
and look carefully at the specs for the reset signal.  How does that compare 
to what is happening on your board?  They are typically things like "must 
delay reset for x ms after power is stable".  Is your power stable long 
enough before reset goes away?


If you are going to have a watchdog, I suggest a way to disable it so you can 
chase bugs.

Years ago, when I was chasing bugs in routers, I would set the watchdog
timer to very long, say 15 minutes.  The guys who were most likely to notice 
a problem knew enough to call me so I could look at it.  If I wasn't around 
or nobody noticed it would reboot itself without causing too much confusion.  
YMMV.


-- 
These are my opinions, not necessarily my employer's.  I hate spam.



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