Lou Calkins

COP's Timing Source

Discussion created by Lou Calkins on Apr 19, 2007
Latest reply on Apr 29, 2007 by David Payne
I was wondering where the COP gets its time base.  It looks like it uses the system clock (maybe BUSCLK?) and has taps at 2^13 and 2^18 for detecting timeout.  So, if my clock system is based on the an external crystal and it somehow quits, the micro will not get a COP reset, right?
 
I came from a project which used a different micro and, with the right amount of noise, it would lock up the oscillator circuit, and the WDT along with it.  Oddly enough, taking the reset pin low would pull it out of its state and restart normally.  I was hoping this processor might be based on an internal RC oscillator or something, but it looks like it is also based on the external crystal, right?

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