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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
Содержание MB91150 Series
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Страница 3: ...FUJITSU LIMITED FR30 32 BIT MICROCONTROLLER MB91150 Series HARDWARE MANUAL ...
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Страница 112: ...96 CHAPTER 3 MEMORY SPACE CPU AND CONTROL UNIT ...
Страница 174: ...158 CHAPTER 5 I O PORTS Note DDRI bit 6 is a test bit Always set the bit to 0 The value read from this bit is always 0 ...
Страница 178: ...162 CHAPTER 5 I O PORTS ...
Страница 214: ...198 CHAPTER 7 16 BIT RELOAD TIMER ...
Страница 240: ...224 CHAPTER 8 PPG TIMER ...
Страница 310: ...294 CHAPTER 13 8 10 BIT A D CONVERTER ...
Страница 318: ...302 CHAPTER 14 8 BIT D A CONVERTER ...
Страница 362: ...346 CHAPTER 15 UART ...
Страница 420: ...404 CHAPTER 19 PERIPHERAL STOP CONTROL ...
Страница 428: ...412 CHAPTER 20 CALENDAR MACROS ...
Страница 503: ...487 INDEX INDEX The index follows on the next page This is listed in alphabetic order ...
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