I'm working on a one-off project that is controlling a pair of 90VDC  
motors through Minarik drives (thanks to the list for the earlier  
tip).  It's going to be entirely unsupervised, so just to ease my mind  
I'd like to have some sort of watchdog IC controlling the AC power to  
the motor controllers (through a relay), so that if the IC doesn't get  
the periodic signal from the PIC it will cut the power to the relays  
indefinitely until the microcontroller is brought back online by other  
means and the IC once again receives its watchdog pulse from the micro.

This last part seems to be the catch.  What I'm finding is no shortage  
of ICs that generate a reset pulse on a failure, but I want one that  
holds an output high (or low) until the failure is corrected.  I  
figure I'll use the PIC's internal watchdog to reset itself, but I'd  
like this extra measure of safety to make sure the moving parts don't  
destroy themselves in the event that the PIC should completely fail.

Any suggestions?

-n.
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