HD6417660 RENESAS [Renesas Technology Corp], HD6417660 Datasheet - Page 391

• Manufacturer Part Number: HD6417660
• Description: Renesas 32-Bit RISC Microcomputer
• Manufacturer: RENESAS [Renesas Technology Corp]

6. Before changing the WTCNT after the execution of the frequency change instruction, always
12.3.3
1. Clear the TME bit of WTCSR to 0. If the TME bit is set to 1, the reset or the interval timer
2. Set the WT/IT bit in the WTCSR to 1, set the reset type in the RSTS bit, set the type of count
3. Set the TME bit in WTCSR to 1 to start the count in watchdog timer mode.
4. While operating in watchdog timer mode, rewrite the counter periodically to H'00 to prevent
5. When the counter overflows, the WDT sets the WOVF flag in WTCSR to 1 and generates the
12.3.4
When operating in interval timer mode, interval timer interrupts are generated at every overflow of
the counter. This enables interrupts to be generated at set periods.
1. Clear the TME bit of WTCSR to 0. If the TME bit is set to 1, the reset or the interval timer
2. Clear the WT/IT bit in the WTCSR to 0, set the type of count clock in the CKS2–CKS0 bits,
3. Set the TME bit in WTCSR to 1 to start the count in interval timer mode.
4. When the counter overflows, the WDT sets the IOVF in WTCSR to 1 and an interval timer
5. To clear the interval timer interrupt request in the exception handling routine, clear the flag
confirm that the value of the WTCNT is H'00 by reading the WTCNT.
interrupt might be generated by error operation at the counter overflow.
clock in the CKS2–CKS0 bits, and set the initial value of the counter in the WTCNT.
the counter from overflowing.
type of reset specified by the RSTS bit. The counter then resumes counting.
interrupt might be generated by error operation at the counter overflow.
and set the initial value of the counter in the WTCNT.
interrupt request is sent to INTC. The counter then resumes counting.
which is set in the IOVF bit in WTCSR. For operation of interrupt exception handling, see
section 4, Exception Handling and section 8, Interrupt Controller.
Using Watchdog Timer Mode
Using Interval Timer Mode
Rev. 1.00, 02/04, page 353 of 804