NEC switch Network Card User Manual


 
CHAPTER 12 STANDBY FUNCTION
User’s Manual U12978EJ3V0UD
184
(2) Releasing STOP mode
The STOP mode can be released by the following two sources.
(a) Releasing by unmasked interrupt request
The STOP mode can be released by an unmasked interrupt request. In this case, if interrupts are enabled
to be acknowledged, vectored interrupt servicing is performed, after the oscillation stabilization time has
elapsed. If interrupt acknowledgement is disabled, the instruction at the next address is executed.
Figure 12-4. Releasing STOP Mode by Interrupt
STOP
instruction
Standby
release signal
Wait
( set time by OSTS)
STOP mode
Operation
mode
Oscillation stabilization
wait status
Clock
Operation
mode
Oscillation
stops
Oscillation
Oscillation
Remark The broken lines indicate the case where the interrupt request that has released the standby
mode is acknowledged.