Toshiba Portege 4000, User Manual

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If Something Goes Wrong
Resolving a hardware conflict
Direct Memory Access
Similarly, the data required by the 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.
Plug and Play
With Plug and Play and the Windows
®
operating system, avoiding
hardware conflicts is easy. Plug and Play is a computer standard
that helps the system BIOS (basic input/output system) and the
operating system to automatically assign system resources to Plug
and Play-compliant devices. In theory, if every device connected
to the computer is Plug and Play-compliant, no two devices will
compete for the same system resources. You simply plug in the
device and turn on your computer. Your operating system
automatically configures your system to accommodate the new
device.
However, if you install an older (legacy) device that the operating
system cannot detect, it may have difficulty assigning system
resources to it. As a result, a hardware conflict can occur. To find
out what resources are assigned to the legacy device, refer to the
section “Checking device properties.”
Checking device properties
Device Manager provides a way to view the properties of a device.
Properties include the name of the manufacturer, the type of
device, the drivers installed, and the system resources assigned to
the device.
To check a device’s properties:
1 Click Start , then point to Settings , and click Control Panel .