Datasheet
Section 15 Watchdog Timer 
    Rev. 3.00 Mar. 15, 2006 Page 291 of 526 
   REJ09B0060-0300 
Bit Bit Name 
Initial 
Value R/W Description 
2  WDON  0  R/W  Watchdog Timer On 
TCWD starts counting up when WDON is set to 1 and 
halts when WDON is cleared to 0. 
[Setting condition] 
When 1 is written to the WDON bit while writing 0 to the 
B2WI bit when the TCSRWE bit=1 
[Clearing conditions] 
•  Reset by RES pin 
•  When 0 is written to the WDON bit while writing 0 to 
the B2WI when the TCSRWE bit=1 
1  B0WI  1  R/W  Bit 0 Write Inhibit 
This bit can be written to the WRST bit only when the 
write value of the B0WI bit is 0. This bit is always read 
as 1. 
0  WRST  0  R/W  Watchdog Timer Reset 
[Setting condition] 
When TCWD overflows and an internal reset signal is 
generated 
[Clearing conditions] 
•  Reset by RES pin 
•  When 0 is written to the WRST bit while writing 0 to 
the B0WI bit when the TCSRWE bit=1 










