225
CHAPTER 11 EXTERNAL INTERRUPT CIRCUIT (EDGE)
11.2
Block Diagram of the External Interrupt Circuit
The external interrupt circuit consists of the following two elements:
• Edge detect circuit 0, 1
• External interrupt control register (EIC)
■
Block diagram of the external interrupt circuit
Figure 11.2-1 Block diagram of the external interrupt circuit
●
Edge detect circuit
If the polarity of an edge on the input signal to one of the external interrupt pins (INT0 - INT1) matches the
edge polarity specified for the pin in the EIC register (SL01, SL00, SL11, SL10), the edge detect circuit
sets the corresponding external interrupt request flag bit (EIR0 - EIR1) to "1".
●
EIC register
The EIC register is used for operations such as edge selection, enabling or disabling interrupt requests, and
checking interrupt requests.
1
Se
le
c
to
r
P42/PWC/INT1
IRQ1
Edge detect circuit 1
Pin
EIR1
SL11 SL10
EIE1
0
Se
le
ct
o
r
EIC
P46/INT0
IRQ0
Edge detect circuit 0
Pin
EIR0
SL01 SL00
EIE0
0
1
Summary of Contents for MB89950 Series
Page 2: ......
Page 3: ...FUJITSU LIMITED F2MC 8L 8 BIT MICROCONTROLLER MB89950 950A Series HARDWARE MANUAL ...
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Page 10: ...vi ...
Page 34: ...20 CHAPTER 2 HANDLING DEVICES ...
Page 134: ...120 CHAPTER 6 WATCHDOG TIMER ...
Page 236: ...222 CHAPTER 10 UART ...
Page 276: ...262 CHAPTER 12 LCD CONTROLLER DRIVER ...
Page 310: ...296 APPENDIX ...
Page 311: ...297 INDEX INDEX The index follows on the next page This is listed in alphabetic order ...
Page 316: ...302 INDEX ...
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