Analog Devices SHARC ADSP-214 Series Hardware Reference Manual page 712

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Programming Model

period value into the 32-bit

enabled. Once the watchdog is started, the period value cannot be altered.

To start the watchdog timer:

1. Unlock the WDT configuration registers by writing the unlock

"command" value to the

programming the

By Default, the resonator output is

2. Set the trip counter value for the watchdog timer by writing to the

3. Set the count value for the watchdog timer by writing the count

value into the watchdog period register (

dog timer is not yet enabled, the write to the

automatically pre-loads the

sufficient time must be provided for the write to the

ister to occur (2.5

4. Enable the watchdog timer in

5. Lock the WDT configuration registers by writing to the

the value in the

ware does not serve the watchdog in time,

decrementing until it reaches 0 and the system is reset.

The counter now reloads the

keeps decrementing. Additionally, the WDRO latch bit in the

occurs up to the number of times programmed in the

6. To prevent the watchdog from expiring, software serves the watch-

dog by unlocking the WDT configuration space and performing

dummy writes to the

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cycles max.), before enabling WDT.

expires, WDT holds the

ADSP-214xx SHARC Processor Hardware Reference

). Since the watch-

cycle. If soft-

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