oops, you're right. sorry (was getting confused with another SoC).
That bit stays set so SW can know a WDT occurred.
Well, I can say that the reset code above is the only code in the BSP that writes to the WDT and it seems to work. I reset the board lot of times without having to press the button.
but, your issue is that you cast the address as a uint8_t *, not a uint16_t *
#define WRCSR_R (*(volatile uint8_t *)0xFCFE0004uL)
so...that's not going to clear anything.
