Chapter 9 Introduction to the Server
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Input/Output (I/O)
port
a small amount of
memory assigned to
a device that tempo-
rarily holds small
amounts of data. It
is used to transfer
data between two
locations.
Input/Output (I/O) Port
The Input/Output (I/O) port is a small amount of memory assigned to a
device that temporarily holds small amounts of data. It is used to transfer data
between two locations. The data remains in the I/O port assignment until it can
be moved.
The system has many hardware devices and software programs that depend
on transferring data between hardware and memory locations. When a device
or software program wants to transfer data, it may need to wait until the CPU
is fi nished with its current process. In fact, it may need to wait until several
processes are completed before the CPU can handle the data. The I/O port stores
Figure 9-15.
DMA assignment.
Figure 9-16.
IDE Channel
Properties
dialog box
Advanced Settings
tab. The IDE channel
is assigned to a DMA
channel by enabling
DMA.