![](http://datasheet.mmic.net.cn/380000/-PD784214Y_datasheet_16744924/-PD784214Y_539.png)
539
CHAPTER 25 STAND-BY FUNCTION
(1) Releasing the IDLE mode by NMI input
When the valid edge specified in the external interrupt edge enable registers (EGP0, EGN0) is input by the NMI
input, the IDLE mode is released.
When the IDLE mode is released and the nonmaskable interrupt from the NMI pin input can be accepted,
execution branches to the NMI interrupt service program. If acceptance is not possible (such as when set in the
IDLE mode in the NMI interrupt service program), execution starts again from the instruction following the
instruction that set the IDLE mode. When acceptance is enabled, execution branches to the NMI interrupt service
program (by executing the RETI instruction).
For details about NMI interrupt acceptance, refer to
23.6 Nonmaskable Interrupt Acceptance
.
(2) Releasing the IDLE mode by INTP0 to INTP6 input, watch timer interrupt and key return interrupt
If interrupt masking by INTP0 to INTP6 input is canceled and macro service is prohibited and the valid edge
specified with the external interrupt edge enable register (EGP0, EGN0) is input to INTP0 to INTP6, the IDLE
mode is canceled. If the mask of watch timer interrupt is released and macro service is disabled, an overflow
of watch timer occurres and IDLE mode is released. If key return interrupt masking is canceled and macro service
is prohibited, and a falling edge is input to port 8 (P80 to P87), the IDLE mode is released.
If interrupts can be accepted when released from the IDLE mode and the interrupt enable flag (IE) is set to one,
execution branches to the interrupt service program. If the IE flag is cleared to zero when acceptance is not
possible, execution starts again from the instruction following the instruction that set the IDLE mode.
For details on interrupt acceptance, refer to
23.7 Maskable Interrupt Acceptance
.
(3) Releasing the IDLE mode by RESET input
When RESET input falls from high to low and the reset condition is entered, the oscillator starts oscillating.
Maintain the oscillation stabilization time for the RESET active period. Then, when the RESET rises, normal
operation starts.
The difference from the normal reset operation is the data memory saves the contents before setting the IDLE
mode.