Figure 11.6-2 Operation Of External Interrupt Circuit 2 (Int20) - Fujitsu F2MC-8L Series Hardware Manual

Figure 11.6-2 shows the operation of external interrupt circuit 2 (using the INT20 pin).

Figure 11.6-2 Operation of External Interrupt Circuit 2 (INT20)

Waveform input to
INT20 pin
("L" level detected)
EIE2:IE20
EIF2:IF20
(Same as IRQA state)
Operation of interrupt
handler for IRQA
PDR0: bit 0
Note:
The states of external interrupt pins can be read directly from the port data register (PDR0)
even when the pins are used for external interrupt input.
External interrupt input enabled
Cleared by interrupt handler
Interrupt processing
Readable at any point
11.6 Operation of External Interrupt Circuit 2
Interrupt processing
RETI
RETI
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