Figure 12.2 Block Diagram Of External Interrupt Circuit; Block Diagram Of External Interrupt Circuit - Fujitsu F2MC-8L MB89620 Series Hardware Manual

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12.

Block Diagram of External Interrupt Circuit

The external interrupt circuit consists of four blocks, each with the same interrupt
functions.
Each block contains the following two elements:
• Edge detector (0 to 3)
• External interrupt 1 and 2 control registers (EIC1, EIC2)
n Block Diagram of External Interrupt Circuit
P61/INT1
P60/INT0
P63/INT3
P62/INT2
Edge detector
l
If the edge polarity on the input signal to one of the external interrupt pins (INT0 to INT3)
matches the edge polarity specified for the pin in the EIC1 or EIC2 register (SEL0 to SEL3), the
edge detector sets the corresponding external interrupt request flag bit (EIR0 to EIR3) to "1".
EIC1 and EIC2 registers
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The EIC1 and EIC2 registers are used to select the edge, enable or disable interrupt requests,
and check interrupt requests.
MB89620 series
Edge detector 1
Pin
Pin
EIR1 —
Edge detector 3
Pin
Pin
EIR3 —

Figure 12.2 Block Diagram of External Interrupt Circuit

CHAPTER 12 EXTERNAL INTERRUPT CIRCUIT (EDGE)
Edge detector 0
1
0
SEL1 EIE1 EIR0 —
Edge detector 2
1
0
SEL3 EIE3 EIR2 —
1
0
SEL0 EIE0
EIC1
IRQ0
IRQ1
1
0
SEL2 EIE2
EIC2
IRQ2
IRQ3
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