68332 Watchdog problem

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There are two registers involved with the Software Watchdog (see the SIM
book,
pages 3-7 through 3-9 and pages 3-12 through 3-13)

1.  SYPCR - System Protection Control Register

On power up, we write 0xc0 to this register.  This sets the Software
Watchdog
Enable bit, SWE.  This also enables the clock Prescaler by 512, SWP and SWT
bits.
The ratio selected, 2^18 is divided by the external system crystal
frequency,
32768, to obtain the watchdog timeout in seconds, 8.

I have fiddled around with the HME, BME, and BMT bits, but it made no
difference.


2. SWSR - Software Service Register

This register is written to about every sixth of a second in a task.  If
this
register is not written to, the watchdog times out and asserts the reset
signal.

Perform a watchdog service as follows:

Write 0x55 to the SWSR
Write 0xAA to the SWSR

PROBLEM:  When I disable the task that services the watchdog, I expect in 8
seconds for the system to reset.  In 8 seconds, I hear the fans shut off,
but
the actual reset does not take place. It varies to when it does.. Anywhere
from
several seconds to several minutes afterwards.

Any ideas??




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