XC886/888CLM
Watchdog Timer
User’s Manual
9-1
V1.3, 2010-02
Watchdog Timer, V1.0
9
Watchdog Timer
The Watchdog Timer (WDT) provides a highly reliable and secure way to detect and
recover from software or hardware failures. The WDT is reset at a regular interval that is
predefined by the user. The CPU must service the WDT within this interval to prevent the
WDT from causing an XC886/888 system reset. Hence, routine service of the WDT
confirms that the system is functioning properly. This ensures that an accidental
malfunction of the XC886/888 will be aborted in a user-specified time period.
The WDT is by default disabled.
In debug mode, the WDT is default suspended and stops counting (its debug suspend
bit is default set i.e., MODSUSP.WDTSUSP = 1). Therefore during debugging, there is
no need to refresh the WDT.
Features
•
16-bit Watchdog Timer
•
Programmable reload value for upper 8 bits of timer
•
Programmable window boundary
•
Selectable input frequency of
f
PCLK
/2 or
f
PCLK
/128
*