HD6417144 RENESAS [Renesas Technology Corp], HD6417144 Datasheet - Page 427

• Manufacturer Part Number: HD6417144
• Description: 32-Bit RISC Microcomputer SuperHTM RISC engine Family/SH7144 Series
• Manufacturer: RENESAS [Renesas Technology Corp]

Notes: 1. Only a 0 can be written after reading 1.
Bit
4, 3
2
1
0
Bit Name
—
CKS2
CKS1
CKS0
2. The overflow interval listed is the time from when the TCNT begins counting at H'00
until an overflow occurs.
Initial Value
All 1
0
0
0
R/W
R
R/W
R/W
R/W
Description
Reserved
These bits are always read as 1. The write value
should always be 1.
Clock Select 2 to 0
Select one of eight internal clock sources for input to
TCNT. The clock signals are obtained by dividing
the frequency of the system clock (
frequency for φ = 40 MHz is enclosed in
parentheses*
000: Clock φ/2 (overflow interval: 12.8 μs)
001: Clock φ/64 (overflow interval: 409.6 μs)
010: Clock φ/128 (overflow interval: 0.8 ms)
011: Clock φ/256 (overflow interval: 1.6 ms)
100: Clock φ/512 (overflow interval: 3.3 ms)
101: Clock φ/1024 (overflow interval: 6.6 ms)
110: Clock φ/4096 (overflow interval: 26.2 ms)
111: Clock φ/8192 (overflow interval: 52.4 ms)
Rev.4.00 Mar. 27, 2008 Page 383 of 882
2
.
12. Watchdog Timer
REJ09B0108-0400
φ
). The overflow