CHAPTER 14 STANDBY FUNCTION
User’s Manual U17446EJ3V1UD
243
(a) Release by unmasked interrupt request
When an unmasked interrupt request (8-bit timer H1
Note
, low-voltage detector, external interrupt request) is
generated, the STOP mode is released. After the oscillation stabilization time has elapsed, if interrupt
acknowledgment is enabled, vectored interrupt servicing is carried out. If interrupt acknowledgment is
disabled, the next address instruction is executed.
Note
Only when sets count clock to f
RL
/2
7
Figure 14-5. STOP Mode Release by Interrupt Request Generation
(1) If CPU clock is high-speed internal oscillation clock or external input clock
Operation
mode
Operation mode
Oscillation
STOP
instruction
STOP mode
Standby release
signal
System clock
oscillation
CPU status
Oscillation
Oscillation stops.
Operation
stops
Note
.
Interrupt
request
(2) If CPU clock is crystal/ceramic oscillation clock
Waiting for stabilization
of oscillation
Oscillation stabilization time
(set by OSTS)
(HALT mode status)
Operation
mode
Operation
mode
Oscillation
STOP
instruction
STOP mode
Standby release
signal
System clock
CPU status
Oscillation
Oscillation stops.
Operation
stops
Note
.
Interrupt
request
Note
The operation stop time is 17
μ
s (MIN.), 34
μ
s (TYP.), and 67
μ
s (MAX.).
Remark
The broken lines indicate the case when the interrupt request that has released the standby mode is
acknowledged.