Texas Instruments MSP430x4xx Family, User Manual

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Watchdog Timer Introduction
12-2 Watchdog Timer, Watchdog Timer+
12.1 Watchdog Timer Introduction
The primary function of the watchdog timer (WDT) module is to perform a
controlled system restart after a software problem occurs. If the selected time
interval expires, a system reset is generated. If the watchdog function is not
needed in an application, the module can be configured as an interval timer
and can generate interrupts at selected time intervals.
Features of the watchdog timer module include:
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Four software-selectable time intervals
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Watchdog mode
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Interval mode
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Access to WDT control register is password protected
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Control of RST/NMI pin function
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Selectable clock source
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Can be stopped to conserve power
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Clock fail-safe feature in WDT+
The WDT block diagram is shown in Figure 12−1.
Note: Watchdog Timer Powers Up Active
After a PUC, the WDT module is automatically configured in the watchdog
mode with an initial 32768 clock cycle reset interval using the DCOCLK. The
user must setup or halt the WDT prior to the expiration of the initial reset
interval.