h8s-2649 Renesas Electronics Corporation., h8s-2649 Datasheet - Page 378

• Manufacturer Part Number: h8s-2649
• Description: Renesas 16-bit Single-chip Microcomputer H8s Family/h8s/2600 Series
• Manufacturer: Renesas Electronics Corporation.

Section 12 Watchdog Timer (WDT)
Note:
Rev. 2.00 Dec. 05, 2005 Page 340 of 724
REJ09B0200-0200
Bit
6
5
4, 3
2
1
0
*
Bit Name
WT/IT
TME
—
CKS2
CKS1
CKS0
Only 0 can be written, for flag clearing.
Initial
Value
0
0
All 1
0
0
0
R/W
R/W
R/W
—
R/W
R/W
R/W
Description
Timer Mode Select
Selects whether the WDT is used as a watchdog timer
or interval timer.
0: Interval timer mode
1: Watchdog timer mode
Timer Enable
When this bit is set to 1, TCNT starts counting. When
this bit is cleared, TCNT stops counting and is initialized
to H'00.
Reserved
These bits are always read as 1 and cannot be
modified.
Clock Select 2 to 0
These bits select the clock source to be input to TCNT.
The overflow frequency for φ = 20 MHz is enclosed in
parentheses.
000: Clock φ/2 (frequency: 25.6 µs)
001: Clock φ/64 (frequency: 819.2 µs)
010: Clock φ/128 (frequency: 1.6 ms)
011: Clock φ/512 (frequency: 6.6 ms)
100: Clock φ/2048 (frequency: 26.2 ms)
101: Clock φ/8192 (frequency: 104.9 ms)
110: Clock φ/32768 (frequency: 419.4 ms)
111: Clock φ/131072 (frequency: 1.68 s)