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Hardware
interrupts are used to handle
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communication
to/from peripheral devices
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Hardware
interrupt occurs when an external
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device
sends a signal to the 8088’s interrupt
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request
line along with an interrupt number n on
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the
8088 data lines. The 8088 then:
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1.
Stops whatever is being done
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2.
Jumps to a subroutine n to handle the data going
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to/from
the device
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3.
Returns to whatever was being done
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Software
interrupts
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Can
be used to test the implementation of the interrupt
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handling
routines
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Interrupt
table approach is useful because
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Indirection
given by the interrupt vector means we
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only
need to specify the address of the routine in the
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vector,
can reference the routine using n
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Can
lead to problems if 2 devices expect to use same n
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