D17133CS datasheet(184/289 Pages) NEC

184 / 289 page

CHAPTER 15

STANDBY FUNCTIONS

169

15.3.3 STOP Setting Condition

Cancellation by IRQ

×××

Cancellation by IRQ

• Sets the edge selection (IEGMD1, IEGMD0) for the signal that is input from the INT

pin.

• Sets the modulo register value of the timer (wait time for generation of oscillation

stability).

• Clears the interrupt request flag (IRQ) of the INT pin (to 0).

• Sets the interrupt enable flag (IP) of the INT pin (to 1.)

Cancellation by IRQSIO

• Sets the source clock to the external clock (SIOCK1=0, SIOCK0=0) that is input from

the SCK pin.

• Sets the serial interface to the operable state (SIOTS=1).

• Sets the modulo register value of the timer (wait time for generation of oscillation

stability).

• Clears the interrupt request flag (IRQSIO) of the serial interface (to 0).

• Sets the interrupt enable flag (IPSIO) of the serial interface (to 1).

Caution Be sure to code a NOP instruction immediately before the STOP instruction. The time of one

instruction is generated between the IRQ

××× operation instruction and the STOP instruction by

coding the NOP instruction immediately before the STOP instruction. Therefore, in the case of

the CLR1 IRQ

××× instruction, for example, the clearance of IRQ××× is correctly reflected in the

STOP instruction (Example 1). If a NOP instruction is not coded immediately before the STOP

instruction, the CLR1 IRQ

××× instruction is not reflected in the STOP instruction thus failing to

place the system in STOP mode (Example 2).

D17133CS Datasheet(PDF) 184 Page - NEC