HD6412320 RENESAS [Renesas Technology Corp], HD6412320 Datasheet - Page 625

• Manufacturer Part Number: HD6412320
• Description: Renesas 16-Bit Single-Chip Microcomputer H8S Family H8S-2300 Series
• Manufacturer: RENESAS [Renesas Technology Corp]

13.5.2
If bits CKS2 to CKS0 in TCSR are written to while the WDT is operating, errors may 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.
13.5.3
If the mode is switched from watchdog timer to interval timer, or vice versa, while the WDT is
operating, errors may occur in the incrementation. Software must stop the watchdog timer (by
clearing the TME bit to 0) before switching the mode.
13.5.4
If the WDTOVF output signal * is input to the RES pin of the chip, the chip will not be initialized
correctly. Make sure that the WDTOVF signal * is not input logically to the RES pin. To reset the
entire system by means of the WDTOVF signal * , use the circuit shown in figure 13.9.
Note: * The WDTOVF pin function cannot be used in the F-ZTAT versions.
Note: * The WDTOVF pin function cannot be used in the F-ZTAT versions.
Changing Value of CKS2 to CKS0
Switching between Watchdog Timer Mode and Interval Timer Mode
System Reset by WDTOVF Signal *
Figure 13.9 Circuit for System Reset by WDTOVF Signal (Example)
Reset signal to entire system
Reset input
Rev.6.00 Sep. 27, 2007 Page 595 of 1268
Section 13 Watchdog Timer
Chip
WDTOVF *
REJ09B0220-0600
RES