50
CHAPTER 6 CLOCK CONTROLLER
6.2
Oscillation Stabilization Wait Time
The oscillation stabilization wait time is the time after the oscillator circuit stops
oscillation until the oscillator resumes its stable oscillation at its natural frequency. The
clock controller obtains the oscillation stabilization wait time by counting a set number
of oscillation clock cycles to prevent clock supply to internal circuits.
■
Oscillation Stabilization Wait Time
The clock controller obtains the oscillation stabilization wait time followed by the initiation of oscillation
by counting a set number of oscillation clock cycles to prevent clock supply to internal circuits.
When a state transition request for starting oscillation when the power is turned on or for restarting halted
oscillation at a clock mode change by a reset, an interrupt in standby mode, or by software, the clock
controller automatically waits until the oscillation stabilization wait time for the main clock or subclock has
passed and then causes transition to the next state.
Figure 6.2-1 shows oscillation immediately after being started.
Figure 6.2-1 Behavior of Oscillator Immediately after Starting Oscillation
The main clock oscillation stabilization wait time is counted by using the timebase timer. The subclock
oscillation stabilization wait time is counted by using the watch prescaler. The count can be set in the
oscillation stabilization wait time setting register (WATR). Set it in keeping with the oscillator
characteristics.
When a power-on reset occurs, the oscillation stabilization wait time is fixed to the initial value.
Table 6.2-1 shows the length of oscillation stabilization wait time.
After the oscillation stabilization wait time of the main clock ends, the oscillation stabilization wait time of
subclock measurement is begun.
■
PLL Clock Oscillation Stabilization Wait Time
As with the oscillation stabilization wait time of the oscillator, the clock controller automatically waits for
(
)
Oscillation stabilization
wait time
Normal operation
Operation after returning
from stop mode or a reset
Oscillation started
X1
Oscillation time of
oscillator
Oscillation stabilized
Table 6.2-1 Oscillation Stabilization Wait Time
Clock
Factor
Oscillation Stabilization Wait Time
Main clock
Power-on reset
Initial value: (2
14
-2)/F
CH
, where F
CH
is the main clock frequency
(specified when ROM is ordered for mask products)
Other than power-on reset
Register setting value (WATR:MWT3, MWT2, MWT1, MWT0)
Subclock
(Two-system clock product)
Power-on reset
Initial value: (2
15
-2)/F
CL
, where F
CL
is the subclock frequency.
Other than power-on reset
Register setting value (WATR:SWT3, SWT2, SWT1, SWT0)
Summary of Contents for F2 MC-8FX Family
Page 2: ......
Page 4: ......
Page 34: ...20 CHAPTER 1 DESCRIPTION ...
Page 38: ...24 CHAPTER 2 HANDLING DEVICES ...
Page 39: ...25 CHAPTER 3 MEMORY SPACE This chapter describes memory space 3 1 Memory Space 3 2 Memory Map ...
Page 56: ...42 CHAPTER 5 CPU ...
Page 73: ...59 CHAPTER 6 CLOCK CONTROLLER ...
Page 96: ...82 CHAPTER 6 CLOCK CONTROLLER ...
Page 104: ...90 CHAPTER 7 RESET ...
Page 105: ...91 CHAPTER 8 INTERRUPTS This chapter explains the interrupts 8 1 Interrupts ...
Page 174: ...160 CHAPTER 10 TIMEBASE TIMER ...
Page 184: ...170 CHAPTER 10 TIMEBASE TIMER ...
Page 218: ...204 CHAPTER 13 WATCH PRESCALER ...
Page 257: ...243 CHAPTER 16 8 16 BIT COMPOSITE TIMER ...
Page 261: ...247 CHAPTER 16 8 16 BIT COMPOSITE TIMER ...
Page 288: ...274 CHAPTER 16 8 16 BIT COMPOSITE TIMER ...
Page 301: ...287 CHAPTER 17 16 BIT PPG TIMER ...
Page 316: ...302 CHAPTER 17 16 BIT PPG TIMER ...
Page 382: ...368 CHAPTER 21 UART SIO DEDICATED BAUD RATE GENERATOR ...
Page 390: ...376 CHAPTER 22 I2C ...
Page 395: ...381 CHAPTER 22 I2C ...
Page 399: ...385 CHAPTER 22 I2C ...
Page 430: ...416 CHAPTER 23 10 BIT A D CONVERTER ...
Page 476: ...462 CHAPTER 24 LCD CONTROLLER ...
Page 482: ...468 CHAPTER 25 LOW VOLTAGE DETECTION RESET CIRCUIT ...
Page 494: ...480 CHAPTER 26 CLOCK SUPERVISOR ...
Page 507: ...493 CHAPTER 27 REAL TIME CLOCK ...
Page 523: ...509 CHAPTER 27 REAL TIME CLOCK ...
Page 532: ...518 CHAPTER 27 REAL TIME CLOCK ...
Page 536: ...522 CHAPTER 28 256 KBIT FLASH MEMORY ...
Page 554: ...540 CHAPTER 28 256 KBIT FLASH MEMORY ...
Page 564: ...550 CHAPTER 29 EXAMPLE OF SERIAL PROGRAMMING CONNECTION ...
Page 595: ...581 INDEX INDEX The index follows on the next page This is listed in alphabetic order ...
Page 596: ...582 INDEX Index ...
Page 597: ...583 INDEX ...
Page 600: ...586 Pin Function Index ...
Page 602: ......