Figure 12.3A Block Diagram Of External Interrupt Circuit Pins; Structure Of External Interrupt Circuit - Fujitsu F2MC-8L MB89620 Series Hardware Manual

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12.

Structure of External Interrupt Circuit

This section describes the pins, pin block diagram, registers, and interrupt sources of
the external interrupt circuit.
n External Interrupt Circuit Pins
The external interrupt circuit uses four external interrupt pins.
The external interrupt pins can function either as external interrupt inputs (hysteresis inputs) or
as input-only ports.
Although the P60/INT0 to P63/INT3 pins continuously function as an external interrupt input, the
external interrupt circuit does not output interrupt requests if an interrupt output is disabled for
the pin. The pin states can be read directly from the port data register (PDR6) at any time.
Table 12.3 External Interrupt Circuit Pins
External interrupt pin
INT0 to INT3: The external interrupt circuit generates the interrupt request corresponding to the
n Block Diagram of External Interrupt Circuit Pins
Note: Pins with a pull-up resistor (optional) go to the pull-up state.
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CHAPTER 12 EXTERNAL INTERRUPT CIRCUIT (EDGE)
When used as an external interrupt
input (interrupt request output enabled)
P60/INT0
P61/INT1
P62/INT2
P63/INT3
pin when an edge of the specified polarity is input.
PDR
(Port data register)
PDR read
To edge detector

Figure 12.3a Block Diagram of External Interrupt Circuit Pins

INT0 (EIC1: EIE0 = "1")
INT1 (EIC1: EIE1 = "1")
INT2 (EIC2: EIE2 = "1")
INT3 (EIC2: EIE3 = "1")
Input buffer
When used as an input-only port
(interrupt request output disabled)
P60 (EIC1: EIE0 = "0")
P61 (EIC1: EIE1 = "0")
P62 (EIC2: EIE2 = "0")
P63 (EIC2: EIE3 = "0")
Pull-up resistor
(optional)
Approx. 50 kΩ/5.0 V
Pin
P60/INT0 to P63/INT3
MB89620 series