SPRUJ79 November 2024 F29H850TU , F29H859TU-Q1
A High Priority Watchdog can be enabled to monitor if the process associated with servicing the High Priority Interrupt has failed to do so. Count down starts from a Pre-Load value and triggers the High Priority Watchdog Interrupt when the time has expired. As long as at least one enabled error associated with the High Priority Interrupt is outstanding, the Watchdog continues to count down.
The Watchdog only triggers the High Priority Watchdog Interrupt a single time until and unless the Interrupt is cleared. The High Priority Interrupt can be cleared with the High Priority Watchdog Interrupt Status/Clear Register or by writing the EOI vector to the EOI Interrupt Register.
If the Watchdog value is non-zero and all High Priority errors are cleared, the Watchdog timer resets to the Pre-Load value and waits until the next High Priority error to begin counting down again.
An MMR write to the Pre-Load value overwrites the Watchdog counter value if the Watchdog is inactive. If the Watchdog is counting down, a write to the Pre-Load value does not have any effect until the Watchdog is once again inactive.
If the Pre-Load value is zero, a High Priority Watchdog Interrupt is triggered when an error associated with the High Priority Interrupt occurs.