SH7101 Datasheet, PDF (297/486 Pages) Renesas Technology Corp – 32-Bit RISC Microcomputer

Section 9 Watchdog Timer
9. Watchdog Timer
The watchdog timer (WDT) is an 8-bit timer that can reset this LSI internally if the counter
overflows without rewriting the counter value due to a system crash or the like.
When this watchdog function is not needed, the WDT can be used as an interval timer. In interval
timer operation, an interval timer interrupt is generated each time the counter overflows.
The block diagram of the WDT is shown in figure 9.1.
9.1 Features
• Selectable from eight counter input clocks.
• Switchable between watchdog timer mode and interval timer mode
• Clears software standby mode
In watchdog timer mode
• Output WDTOVF signal
• If the counter overflows, it is possible to select whether this LSI is internally reset or not.
In interval timer mode
• If the counter overflows, the WDT generates an interval timer interrupt (ITI).
WDT0400A_010020030200
Rev.2.00 Sep. 27, 2007 Page 263 of 448
REJ09B0394-0200