Datasheet

Section 13 Watchdog Timer
Rev.6.00 Sep. 27, 2007 Page 596 of 1268
REJ09B0220-0600
13.5.5 Internal Reset in Watchdog Timer Mode
The chip is not reset internally if TCNT overflows while the RSTE bit is cleared to 0 during
watchdog timer operation, but TCNT and TCSR of the WDT are reset.
TCNT, TCSR, and RSTCR cannot be written to while the WDTOVF signal
*
is low. Also note that
a read of the WOVF flag is not recognized during this period. To clear the WOVF flag, therefore,
read RSTCSR after the WDTOVF signal
*
goes high, then write 0 to the WOVF flag.
Note: * The WDTOVF pin function cannot be used in the F-ZTAT versions.