Datasheet
Section 14 Watchdog Timer (WDT) 
R01UH0310EJ0500 Rev. 5.00    Page 857 of 1384 
Sep 25, 2012     
H8S/2426, H8S/2426R, H8S/2424 Group 
14.3.3  Reset Control/Status Register (RSTCSR) 
RSTCSR controls the generation of the internal reset signal when TCNT overflows, and selects 
the type of internal reset signal. RSTCSR is initialized to H'1F by a reset signal from the RES pin, 
but not by the WDT internal reset signal caused by overflows. 
Bit  Bit Name  Initial Value  R/W  Description 
7 WOVF 0  R/(W)
*
  Watchdog Timer Overflow Flag 
This bit is set when TCNT overflows in watchdog 
timer mode. This bit cannot be set in interval timer 
mode, and only 0 can be written. 
[Setting condition] 
Set when TCNT overflows (changed from H'FF to 
H'00) in watchdog timer mode 
[Clearing condition] 
Cleared by reading RSTCSR when WOVF = 1, 
and then writing 0 to WOVF 
6 RSTE 0  R/W Reset Enable 
Specifies whether or not a reset signal is 
generated in the chip if TCNT overflows during 
watchdog timer operation. 
0: Reset signal is not generated even if TCNT 
overflows 
(Though this LSI is not reset, TCNT and TCSR 
in WDT are reset) 
1: Reset signal is generated if TCNT overflows 
5  ⎯ 0  R/W Reserved 
Can be read and written, but does not affect 
operation. 
4 to 0  ⎯ All 1  ⎯ Reserved 
These bits are always read as 1 and cannot be 
modified. 
Note:  *  Only a write of 0 is permitted, to clear the flag. 










