NEC PD750008 - Manual (Page 223)

203
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 are
enabled.
<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
••
••
••
••
•
••
••
••
••
••
••
••
••
••
••
••
••
••
••
••
••
••
••
••
••
••
••
••
••
••
••
••
•
••
••
••
••
•