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If Something Goes Wrong
Resolving a hardware conflict
2
Click the
Hardware
link in the window’s left pane.
A list of category links appear.
3
Click the
Fixing a hardware problem
link.
4
Choose from specific topics and follow the steps.
If there is still a problem, the operating system should display a
message that explains what the conflict is.
A plan of action
The smooth operation of the system depends on the interaction of
all devices, programs, and features. If the system or one of its
attached devices is not working, resolving the problem can be time-
consuming and frustrating.
The recommended procedure for getting multiple devices to work
together is to add and set up one device at a time. After you add
each device, test it to make sure it and all previously connected
devices work.
The device most recently connected to the system is the one most
likely to be causing a hardware conflict.
Resolving hardware conflicts on your own
Computer components need resources to accomplish a task. A
device, such as a disk drive or a modem, needs a channel to the
computer’s Central Processing Unit (CPU). It also needs a direct
channel to the computer’s memory to store information as it works.
These channels of communication are commonly referred to as
system resources.
Interrupt Request Channel
The channel to the CPU is called an Interrupt Request (IRQ)
because it interrupts what the processor is doing and requests some
of the processor’s time. If two or more devices use the same IRQ,
the processor does not know which device is asking for attention.
This causes a hardware conflict.
Direct Memory Access
The data required by a device is stored in a specific place or address
in memory called the Direct Memory Access (DMA). The DMA
provides a dedicated channel for adapter cards to bypass the
microprocessor and access memory directly. If two or more devices
use the same DMA, the data required by one device overwrites the
data required by the other, causing a hardware conflict.