INTRODUCTION TO MICROPEOCESSOR
MICROCOMPUTER SYSTEM
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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A0
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CAS2-CAS0
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D7-D0
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IR7-IR0
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Detailed explanation-1: -A cascaded configuration increases the number of interrupts handled by the system. As the maximum number of 8259s interfaced can be 9 (1 master and 8 slaves) the maximum number of interrupts handled can be 64. The master 8259 has ¯SP/¯EN=+5V and the slave has ¯SP/¯EN=0V.
Detailed explanation-2: -To increase number of interrupt pin, we can cascade more number of pins, by using cascade buffer. When we are going to increase the interrupt capability, CSA lines are used to control multiple interrupts.
Detailed explanation-3: -The Intel 8259A Programmable Interrupt Controller handles up to eight vectored priority interrupts for the CPU. It is cascadable for up to 64 vectored priority interrupts without additional circuitry.