ML51/ML54/ML56
Sep. 01, 2020
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Series
Tec
hnical Reference
Manual
interrupt enable bit in the IE and EIE0 SFR. There is also a global enable bit EA bit (I.E.7), which can
be cleared to disable all the interrupts at once. It is set to enable all individually enabled interrupts.
Setting the EA bit to logic 0 disables all interrupt sources regardless of the individual interrupt-enable
settings. Note that interrupts which occur when the EA bit is set to logic 0 will be held in a pending
state, and will not be serviced until the EA bit is set back to logic 1. All interrupt flags that generate
interrupts can also be set via software. Thereby software initiated interrupts can be generated.
Note that every interrupts, if enabled, is generated by a setting as logic 1 of its interrupt flag no matter
by hardware or software. User should take care of each interrupt flag in its own interrupt service
routine (ISR). Most of interrupt flags should be cleared by writing it as logic 0 via software to avoid
recursive interrupt requests.