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CHAPTER 10 EXTERNAL INTERRUPT CONTROL BLOCK
10.4 External Interrupt Request Level
When the request level is the edge request, a minimum of three machine cycles
(peripheral clock machine cycles) are required for edge detection.
When the request input level is in accordance with the level setting, even if the request
input previously issued externally is canceled, the request to the interrupt controller
remains active because the internal source-holding circuit retains it.
To cancel the request to the interrupt controller, clear the external interrupt request
register.
■
External interrupt request level
Figure 10.4-1 "Clearing the source-holding circuit during level setting" shows how the source
holding circuit is cleared when the level is set. Figure 10.4-2 "Interrupt-source input with
interrupts enabled and interrupt request to the interrupt controller" shows how interrupt sources
are input when interrupt sources are enabled and how an interrupt request is issued to the
interrupt controller.
Figure 10.4-1 Clearing the source-holding circuit during level setting
Figure 10.4-2 Interrupt-source Input with interrupts enabled and interrupt request to the interrupt
controller
Interrupt input
Level detection
Source F/F
(Source-holding circuit)
Enable gate
To interrupt controller
Sources are retained until holding circuit is cleared.
Interrupt input
High level
Interrupt request to
interrupt controller
Inactivated by clearing source F/F
Summary of Contents for MB91150 Series
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Page 3: ...FUJITSU LIMITED FR30 32 BIT MICROCONTROLLER MB91150 Series HARDWARE MANUAL ...
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Page 10: ...vi ...
Page 112: ...96 CHAPTER 3 MEMORY SPACE CPU AND CONTROL UNIT ...
Page 178: ...162 CHAPTER 5 I O PORTS ...
Page 214: ...198 CHAPTER 7 16 BIT RELOAD TIMER ...
Page 240: ...224 CHAPTER 8 PPG TIMER ...
Page 310: ...294 CHAPTER 13 8 10 BIT A D CONVERTER ...
Page 318: ...302 CHAPTER 14 8 BIT D A CONVERTER ...
Page 362: ...346 CHAPTER 15 UART ...
Page 420: ...404 CHAPTER 19 PERIPHERAL STOP CONTROL ...
Page 428: ...412 CHAPTER 20 CALENDAR MACROS ...
Page 503: ...487 INDEX INDEX The index follows on the next page This is listed in alphabetic order ...
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