CHAPTER 21 CLOCK MONITOR
User’s Manual U16896EJ2V0UD
605
21.3 Operation
The clock monitor start and stop conditions are as follows.
<Monitor start condition>
Set the CLM.CLME bit to 1
<Monitor stop conditions>
•
When the oscillation stabilization time is counted after the STOP mode has been released
•
When the main clock is stopped (PCC.MCK bit = 1 when subclock operates and PCC.CLS bit = 0 when main
clock operates)
•
When the sampling clock (internal oscillation clock) is stopped
•
When the CPU operates on internal oscillation clock
Table 21-1. Operation Status of Clock Monitor
(When CLME Bit = 1, During Internal Oscillation Clock Operation)
Operation Mode
Status of Main Clock
Status of Internal
Oscillation Clock
Status of Clock Monitor
Normal operation mode
Oscillates
Oscillates
Note 1
Operates
Note 2
HALT mode
Oscillates
Oscillates
Note 1
Operates
Note 2
IDLE mode
Oscillates
Oscillates
Note 1
Operates
Note 2
STOP mode
Stops
Oscillates
Note 1
Stops
Subclock operation mode
Oscillates
Oscillates
Note 1
Operates
Note 2
Sub-IDLE mode
MCK bit = 0
Oscillates Oscillates
Note 1
Operates
Note 2
Subclock operation mode
Stops
Oscillates
Note 1
Stops
Sub-IDLE mode
MCK bit = 1
Stops Oscillates
Note 1
Stops
Internal oscillation clock operation mode
Stops
Oscillates
Note 1
Stops
During reset
Stops
Stops
Stops
Notes 1.
Internal oscillator can be stopped by setting the RCM.RSTOP bit to 1.
(Valid only when specified by mask option/option byte. For details, refer to
CHAPTER 25 MASK
OPTION/OPTION BYTE
).
2.
The clock monitor is stopped while internal oscillator is stopped.