HD6433682 ETC, HD6433682 Datasheet - Page 267

• Manufacturer Part Number: HD6433682
• Description: Renesas 16-Bit Single-Chip Microcomputer H8 Family/H8/300H Tiny Series
• Manufacturer: ETC

14.2.2
TCWD is an 8-bit readable/writable up-counter. When TCWD overflows from H'FF to H'00, the
internal reset signal is generated and the WRST bit in TCSRWD is set to 1. TCWD is initialized to
H'00.
14.2.3
TMWD selects the input clock.
Legend X: Don't care.
Bit
0
Bit
7 to 4
3
2
1
0
Bit
Name Initial Value R/W
WRST 0
Bit Name
CKS3
CKS2
CKS1
CKS0
Timer Counter WD (TCWD)
Timer Mode Register WD (TMWD)
Initial
Value
All 1
1
1
1
1
R/W
R/W
R/W
R/W
R/W
R/W
Description
Watchdog Timer Reset
[Setting condition]
When TCWD overflows and an internal reset signal is
generated
[Clearing condition]
Description
Reserved
These bits are always read as 1.
Clock Select 3 to 0
Select the clock to be input to TCWD.
1000: Internal clock: counts on /64
1001: Internal clock: counts on /128
1010: Internal clock: counts on /256
1011: Internal clock: counts on /512
1100: Internal clock: counts on /1024
1101: Internal clock: counts on /2048
1110: Internal clock: counts on /4096
1111: Internal clock: counts on 8192
0XXX: Internal oscillator
For the internal oscillator overflow periods, see section
23, Electrical Characteristics.
Reset by RES pin
When 0 is written to the WRST bit while writing 0 to the
B0WI bit when the TCSRWE bit=1
Rev. 3.00, 05/03, page 237 of 472