steht im UserGuide...
z.B. für den MSP430F449
Interrupt Flag Registers P1IFG, P2IFG
Each PxIFGx bit is the interrupt flag for its corresponding I/O pin and
is set
when the selected input signal edge occurs at the pin. All PxIFGx
interrupt
flags request an interrupt when their corresponding PxIE bit and the GIE
bit
are set. Each PxIFG flag must be reset with software. Software can also
set
each PxIFG flag, providing a way to generate a software-initiated
interrupt.
Bit = 0: No interrupt is pending
Bit = 1: An interrupt is pending
Only transitions, not static levels, cause interrupts. If any PxIFGx
flag becomes
set during a Px interrupt service routine or is set after the RETI
instruction of
a Px interrupt service routine is executed, the set PxIFGx flag
generates
another interrupt. This ensures that each transition is acknowledged.
1 |
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2 | Software can also set each PxIFG flag, providing a way to generate a software-initiated interrupt.
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