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CHAPTER 3 CPU
3.6.3 System Clock Control Register (SYCC)

The system clock control register (SYCC) manages clock settings such as selection of

the clock speed and oscillation stabilization wait time.

Configuration of the System Clock Control Register (SYCC)

Figure 3.6-5 Configuration of System Clock Control Register (SYCC)

CS1CS0
0064/FCH(5.12 µs)
0 1 16/FCH(1.28µs)
108/FCH (0.64 µs)
114/FCH (0.32µs)
WT1 WT0
00
01
10
11
bit7 bit6 bit5 bit4 bit3bit2 bit1 bit0
0007HWT1SCM WT0 CS1CS0 1--MM-00B
R/WR R/W R/W R/W
R : Read only
R/W: Readable/Writable
: Unused
M : Mask option
: Initial value
Address Initial value
Clock speed selection bits
Instruction cycle (when FCH is 12.5 MHz)
Oscillation stabilization wait time selection bits
Oscillation stabilization wait time according to
output of the time-base timer (when FCH is 12.5 MHz)
Setting prohibited
Approx. 214/FCH (approx. 1.31 ms)
Approx. 217/FCH (approx. 10.5 ms)
Approx. 218/FCH (approx. 21.0 ms)
SCM
0
1
System clock monitor bit
Clock stopping or waiting for stabilization of oscillation
Active mode