Fujitsu F2MCTM-16LX User Manual

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CHAPTER 17  DTP/EXTERNAL INTERRUPTS
Precautions on interrupts
When the DTP/external interrupt is used as the external interrupt function, no return from interrupt
processing can be made with the DTP/external interrupt request flag bit set to "1" (EIRR1:ER) and the
DTP/external interrupt request set to "enabled" (ENIR1:EN = 1). Always set the DTP/external interrupt
request flag bit to 0 (EIRR1:ER) at interrupt processing.
When the level detection is set in the detection level setting register and the level that becomes the
interrupt factor remains input, the DTP/external interrupt request flag bit is reset immediately even when
cleared (EIRR1:ER = 0). Disable the DTP/external interrupt request output as needed (ENIR1:EN = 0),
or cancel the interrupt factor itself.