h8s-2169 Renesas Electronics Corporation., h8s-2169 Datasheet - Page 451

• Manufacturer Part Number: h8s-2169
• Description: Renesas 16-bit Single-chip Microcomputer H8s Family/h8s/2100 Series
• Manufacturer: Renesas Electronics Corporation.

14.5.2
If bits CKS2 to CKS0 in TCSR are written to while the WDT is operating, errors could occur in
the incrementation. Software must stop the watchdog timer (by clearing the TME bit to 0) before
changing the value of bits CKS2 to CKS0.
14.5.3
If the mode is switched from watchdog timer to interval timer, or vice versa, while the WDT is
operating, errors could occur in the incrementation. Software must stop the watchdog timer (by
clearing the TME bit to 0) before switching the mode.
14.5.4
If the RESO output signal is input to the chip’s RES pin, the chip will not be initialized correctly.
Ensure that the RESO signal is not logically input to the chip’s RES pin. When resetting the entire
system with the RESO signal, use a circuit such as that shown in figure 14.8.
Reset signal to entire system
Changing Value of CKS2 to CKS0
Switching between Watchdog Timer Mode and Interval Timer Mode
System Reset by RESO
Figure 14.8 Sample Circuit for System Reset by RESO
Reset input
RESO Signal
RESO
RESO
Rev. 3.00 Jan 18, 2006 page 423 of 1044
Section 14 Watchdog Timer (WDT)
RESO
RESO Signal
RESO
RES
RESO
REJ09B0280-0300
Chip