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ä |
CPU
issues request to a DMA
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module
(separate module or
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incorporated
into I/O module)
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ä |
DMA
module transfers a
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block
of data directly to or
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from
memory (without going
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through
CPU)
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ä |
An
interrupt is sent when the
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task
is complete
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ä |
The
CPU is only involved at
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the
beginning and end of the
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transfer
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ä |
The
CPU is free to perform
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other
tasks during data transfer
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