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CHAPTER 6 INTERRUPT AND TEST FUNCTIONS
(1) Interrupt enable/disable<1> A RESET signal disables all interrupts.<2> Interrupt enable flags are set by the EI IExxx instruction. At this stage, all interrupts are disabled.<3> The interrupt master enable flag is set by the EI instruction. At this stage, INT0 and INTT0 areenabled.<4> An interrupt enable flag is cleared by the DI IExxx instruction to disable INT0.<5> The DI instruction disables all interrupts.

Interrupt disabled

INT0 and INTT0 enabled

INTT0 enabled

Interrupt disabled

<Main program>

<1> Reset

<2> EI IE0

EI IET0

<3> EI

<4> DI IE0

<5> DI

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