Plug And Play - Toshiba Satellite Pro 4600 Series User Manual

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If Something Goes Wrong
Resolving a hardware conflict
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 channel, the processor does not know which device is asking
for attention. This causes 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 Windows 98 Second Edition, avoiding
hardware conflicts is easy. Plug and Play is a computer standard
that helps the 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. Windows 98 Second Edition
automatically sets up your system to accommodate the new
device.
However, if you install an older (legacy) device that Windows 98
Second Edition cannot recognize, the operating system may have