Customer would like to use watchdog on KV3x and observed issue with integrating it into his application.
- Watchdog clock source: LPO at 1 kHz. It is necessary to have independent clock for watchdog which must be different from core clock
- Timeout value: 10 s (register value - 10000 at 1 kHz)
- Window value: 0
- Prescaler value: 0
- Watchdog is refreshed periodically in the interrupt triggered by SysTick (IsrSysTick interrupt handler) every 1 ms
a) The watchdog is not refreshed with the period of 1 ms
b) How to refresh watchdog during the startup code when it is difficult to keep period larger than 1 ms? Will the watchdog be updated correctly even if the update will happen several times in 1 ms period?
1) The issue is probably caused by watchdog input clock which is 1 kHz (1 ms)
2) Is it possible to update watchdog anytime regardless of watchdog source clock which means more often than just once in 1 ms period? If so, how does this work?
3) Since it is synchronous design the watchdog peripheral module is probably triggered with 1 kHz clock.
4) How can we manage watchdog update in startup code? It is difficult to keep 1 ms time frame. It is changing with startup code complexity and it is application dependent
Thanks for your help
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