SH7604 Datasheet, PDF (347/633 Pages) Hitachi Semiconductor – Hardware Manual

12.4.4 System Reset with WDTOVF
If a WDTOVF signal is input to the RES pin, the device cannot initialize correctly. Avoid logical
input of the WDTOVF output signal to the RES input pin. To reset the entire system with the
WDTOVF signal, use the circuit shown in figure 12.9.
Reset input
SH microprocessor
RES
Reset signal to
entire system
WDTOVF
Figure 12.9 Example of Circuit for System Reset with WDTOVF Signal
12.4.5 Internal Reset in Watchdog Timer Mode
If the RSTE bit is cleared to 0 in watchdog timer mode, the chip will not reset internally when a
WTCNT overflow occurs, but WTCNT and WTCSR in the WDT will reset.
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