HD64F3670 RENESAS [Renesas Technology Corp], HD64F3670 Datasheet - Page 177

• Manufacturer Part Number: HD64F3670
• Description: Hitachi Single-Chip Microcomputer
• Manufacturer: RENESAS [Renesas Technology Corp]

Bit Bit Name
0
12.2.2 Timer Counter WD (TCWD)
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.
12.2.3 Timer Mode Register WD (TMWD)
TMWD selects the input clock.
Bit
7 to 4
3
2
1
0
Legend X: Don't care.
WRST
Bit Name
CKS3
CKS2
CKS1
CKS0
Initial Value R/W
0
Initial Value R/W
All 1
1
1
1
1
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
17, Electrical Characteristics.
Reset by
When 0 is written to the WRST bit while writing 0 to the
B0WI bit when the TCSRWE bit=1
# $
pin
Rev. 2.0, 03/02, page 153 of 298