INTERRUPT CONTROL UNIT
8-30
External interrupt acknowledge cycles must be run for every maskable interrupt. Therefore, the
interrupt response time for every interrupt will be 55 clocks, as shown in Figure 8-21.
Figure 8-21. Interrupt Response Time in Slave Mode
8.5.3
Initializing the Interrupt Control Unit for Master Mode
Follow these steps to initialize the Interrupt Control Unit for Master mode.
1.
Determine which interrupt sources you want to use.
2.
Determine whether to use the default priority scheme or devise your own.
3.
Program the Interrupt Control register for each interrupt source.
— For external interrupt pins, select edge or level triggering.
— For INT0 or INT1, enable cascade mode, special fully nested mode, or both, if you
wish to use them.
— If you are using a custom priority scheme, program the priority level for each interrupt
source.
4.
Program the Priority Mask with a priority mask level, if you wish to mask interrupts based
on priority. (The default is level seven, which enables all interrupt levels.)
Clocks
5
4
2
4
5
4
3
4
4
4
3
4
4
5
Total 55
First instruction fetch
from interrupt routine
INTA
IDLE
INTA
IDLE
READ IP
IDLE
READ CS
IDLE
PUSH FLAGS
IDLE
PUSH CS
PUSH IP
IDLE
Interrupt presented to Interrupt Control Unit
Interrupt presented to external 82C59A
A1200-A0
Содержание 80C186XL
Страница 1: ...80C186XL 80C188XL Microprocessor User s Manual...
Страница 2: ...80C186XL 80C188XL Microprocessor User s Manual 1995...
Страница 18: ...1 Introduction...
Страница 19: ......
Страница 27: ......
Страница 28: ...2 Overview of the 80C186 Family Architecture...
Страница 29: ......
Страница 79: ......
Страница 80: ...3 Bus Interface Unit...
Страница 81: ......
Страница 127: ......
Страница 128: ...4 Peripheral Control Block...
Страница 129: ......
Страница 137: ......
Страница 138: ...5 ClockGenerationand Power Management...
Страница 139: ......
Страница 154: ...6 Chip Select Unit...
Страница 155: ......
Страница 178: ...7 Refresh Control Unit...
Страница 179: ......
Страница 193: ......
Страница 194: ...8 Interrupt Control Unit...
Страница 195: ......
Страница 227: ......
Страница 228: ...9 Timer Counter Unit...
Страница 229: ......
Страница 253: ......
Страница 254: ...10 Direct Memory Access Unit...
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Страница 284: ...11 Math Coprocessing...
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Страница 302: ...12 ONCE Mode...
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Страница 306: ...A 80C186 Instruction Set Additions and Extensions...
Страница 307: ......
Страница 318: ...B Input Synchronization...
Страница 319: ......
Страница 322: ...C Instruction Set Descriptions...
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Страница 371: ......
Страница 372: ...D Instruction Set Opcodes and Clock Cycles...
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Страница 396: ...Index...
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