CHAPTER 5 CLOCK GENERATORS
User’s Manual U17446EJ3V1UD
80
Figure 5-10. Timing Chart of Default Start by Crystal/Ceramic Oscillator
V
DD
Crystal/ceramic
oscillator clock
PCC = 02H, PPCC = 02H
(a)
(b)
(c)
H
RESET
System clock
Internal reset
CPU clock
Option byte is read.
System clock is selected.
(Operation stops
Note 1
)
Clock oscillation
stabilization
time
Note 2
Notes 1.
Operation stop time is 276
μ
s (MIN.), 544
μ
s (TYP.), and 1.074 ms (MAX.).
2.
The clock oscillation stabilization time for default start is selected by the option byte. For details, refer
to
CHAPTER 18 OPTION BYTE
. The oscillation stabilization time that elapses after the STOP mode
is released is selected by the oscillation stabilization time select register (OSTS).
(a) The internal reset signal is generated by the power-on-clear function on power application, the option byte is
referenced after reset, and the system clock is selected.
(b) After the high-speed internal oscillation clock is generated, the option byte is referenced and the system
clock is selected. In this case, the crystal/ceramic oscillator clock is selected as the system clock.
(c) If the system clock is the crystal/ceramic oscillator clock, it starts operating as the CPU clock after clock
oscillation is stabilized. The wait time is selected by the option byte. For details, refer to
CHAPTER 18
OPTION BYTE
.
Содержание 78K0S/KB1+
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