Specifications

Watchdog Timer
Stage 1 Delay
The stage 1 delay has a default range of 60 ms minimum and 100 ms
maximum. The minimum delay time means that the watchdog timer
must be strobed with a period of less than 60 ms to prevent stage 1
from generating a non-maskable interrupt. The maximum delay time
means that it could take up to 100 ms after the watchdog timer is
strobed before the non-maskable interrupt occurs.
Stage 2 T
imer
The second stage of the watchdog timer generates a reset to the local
CPU if the watchdog timer is jumper selected and armed and a strobe
does not occur within the time period defined by the Stage 2 Delay
functional block.
Stage 2
Delay
The stage 2 delay has a default range of 250 ms minimum and
1000 ms maximum. The stage 1 delay time must be subtracted from
the stage 2 delay time to determine how long the non-maskable inter-
rupt service routine must strobe the stage 2 timer to prevent a local
reset. For the default configuration, this time is 150 (250 - 100) ms
minimum and 940 (1000 - 60) ms maximum. The minimum delay
time means that the watchdog timer must be strobed sooner than
150 ms after the stage 1 timeout to prevent a local reset. The maxi-
mum delay time means that it could take up to 940 ms after the non-
maskable interrupt before the local reset occurs if the watchdog is not
strobed.
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