CHAPTER 15 STANDBY FUNCTION
User’s Manual U14826EJ5V0UD
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(2) Releasing STOP mode
STOP mode can be released by the following three sources:
(a) Releasing by unmasked interrupt request
STOP mode is released by an unmasked interrupt request. In this case, vectored interrupt servicing is
performed if interrupt acknowledgment is enabled after the oscillation stabilization time has elapsed. If
interrupt acknowledgment is disabled, the instruction at the next address is executed.
Figure 15-4. Releasing STOP Mode by Interrupt
STOP
instruction
Standby
release signal
Wait
Note
(time set by OSTS)
STOP mode
Operating
mode
Oscillation stabilization
wait status
Clock
Operating
mode
Oscillation
stop
Oscillation
Oscillation
Note
There is no OSTS in the
µ
PD789861 Subseries, and the wait is fixed at 2
7
/f
CC
.
Remark
The broken lines indicate the case where the interrupt request that has released standby
mode is acknowledged.
(b) Releasing by non-maskable interrupt request of key return
STOP mode is released regardless of whether interrupts are enabled or disabled, and vectored interrupt
servicing is performed.