CHAPTER 6. INTERRUPT FUNCTIONS

(3) Pending interrupt execution - interrupt input in interrupt disabled state

<Main program>

Reset

EI IE0

<INT0 Service Program>

INT0

EI

INTCSI

RETI

<INTCSI Service Program>

EI IECSI

RETI

Although INT0 is set in the interrupt disabled state, the interrupt flag is held pending.

The INT0 service program is started at point at which interrupts are enabled by the EI instruction.

Same as .

4The INTCSI service routine is started at the point at which the pending INTCSI is enabled.

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NEC PD75P402, PD75402A user manual 139, EI IE0, ➂ Intcsi Reti, ➃ EI Iecsi Reti