NEC 78K0 Series User Manual page 519

(a) Release by unmasked interrupt request
When an unmasked interrupt request is generated, the STOP mode is released.
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.
Figure 21-6. STOP Mode Release by Interrupt Request Generation
(1) When high-speed system clock is used as CPU clock
Standby release signal
Status of CPU
High-speed
system clock
(X1 oscillation)
(2) When internal high-speed oscillation clock is used as CPU clock
Standby release signal
(internal high-speed
Status of CPU
Internal high-speed
oscillation clock
Remark The broken lines indicate the case when the interrupt request that has released the standby mode
is acknowledged.
CHAPTER 21 STANDBY FUNCTION
STOP
instruction
Operating mode
(high-speed
system clock) STOP mode
Oscillates Oscillation stopped
STOP
instruction
Normal operation
oscillation clock)
STOP mode
Oscillation stopped
Oscillates
Preliminary User's Manual U17260EJ3V1UD
Wait
(set by OSTS)
Oscillation stabilization wait
(HALT mode status)
Oscillates
Oscillation stabilization time (set by OSTS)
Normal operation
(internal high-speed
oscillation clock)
Oscillates
Wait for oscillation
accuracy
stabilization
After the oscillation
Operating mode
(high-speed
system clock)
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