Configuration Of External Interrupt Circuit - Fujitsu F2MC-8FX Hardware Manual

18.2

Configuration of External Interrupt Circuit

The external interrupt circuit consists of the following blocks:
• Edge detection circuit
• External interrupt control register
Block Diagram of External Interrupt Circuit
Figure 18.2-1 shows the block diagram of the external interrupt circuit.
Figure 18.2-1 Block Diagram of External Interrupt Circuit (Unit0)
Pin
INT00
Pin
INT01
External interrupt
control register
(EIC)
* : Only for INT 00 pin of unit 0
See "CHAPTER 19 INTERRUPT PIN SELECTION CIRCUIT".
Edge detection circuit
When the polarity of the edge detected on a signal inputted to an external interrupt circuit pin (INT)
matches the polarity of the edge selected in the interrupt control register (EIC), the corresponding external
interrupt request flag bit (EIR) is set to "1".
External interrupt control register (EIC)
This register is used to select the valid edge, enable or disable interrupt requests, check for interrupt
requests, etc.
Interrupt pin select circuit *
Edge detection circuit 1
10
01
11
EIR1 SL11 SL10 EIE1
CHAPTER 18 EXTERNAL INTERRUPT CIRCUIT
Edge detection circuit 0
10
01
11
EIR0 SL01 SL00 EIE0
Interrupt request 0
Interrupt request 1
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