HD6413008VF25 Datasheet, PDF (359/688 Pages) Renesas Technology Corp – Old Company Name in Catalogs and Other Documents

11. Watchdog Timer
Bit 6—Timer Mode Select (WT/IT): Selects whether to use the WDT as a watchdog timer or
interval timer. If used as an interval timer, the WDT generates an interval timer interrupt request
when TCNT overflows. If used as a watchdog timer, the WDT generates a reset signal when
TCNT overflows.
Bit 6
WT/IT
0
1
Description
Interval timer: requests interval timer interrupts
Watchdog timer: generates a reset signal
(Initial value)
Bit 5—Timer Enable (TME): Selects whether TCNT runs or is halted. When WT/IT = 1, clear
the software standby bit (SSBY) to 0 in SYSCR before setting TME. When setting SSBY to 1,
TME should be cleared to 0.
Bit 5
TME
0
1
Description
TCNT is initialized to H'00 and halted
TCNT is counting
(Initial value)
Bits 4 and 3—Reserved: These bits cannot be modified and are always read as 1.
Bits 2 to 0—Clock Select 2 to 0 (CKS2 to CKS0): These bits select one of eight internal clock
sources, obtained by prescaling the system clock (φ), for input to TCNT.
Bit 2
CKS2
0
1
Bit 1
CKS1
0
1
0
1
Bit 0
CKS0
0
1
0
1
0
1
0
1
Description
φ/2
φ /32
φ /64
φ /128
φ /256
φ /512
φ /2048
φ /4096
(Initial value)
Rev.4.00 Aug. 20, 2007 Page 313 of 638
REJ09B0395-0400