NEC 78K0 User Manual page 459

(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
Standby release signal
Status of CPU
Operating mode
(X1 input clock)
X1 input clock
Standby release signal
Operating mode
Status of CPU
(Ring-OSC clock)
Ring-OSC clock
Remarks 1. The broken lines indicate the case when the interrupt request that has released the standby
mode is acknowledged.
2. f : Ring-OSC clock oscillation frequency
R
CHAPTER 21 STANDBY FUNCTION
(1) When X1 input clock is used as CPU clock
STOP
instruction
STOP mode
Oscillates Oscillation stopped
(2) When Ring-OSC clock is used as CPU clock
STOP
instruction
*
STOP mode
User's Manual U15947EJ2V0UD
Wait
(set by OSTS)
Oscillation stabilization wait
(HALT mode status)
Oscillates
Oscillation stabilization time (set by OSTS)
Operation
Operating mode
stopped
(Ring-OSC clock)
(17/f )
R
Oscillates
After the oscillation
Operating mode
(X1 input clock)
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