Toshiba 2805-S301 - Satellite - PIII 650 MHz, Руководство пользователя

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If Something Goes Wrong
Resolving a hardware conflict
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
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
®
Millennium Edition
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 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. Simply plug in the device and turn on your computer.
The operating system automatically sets up your system to
accommodate the new device.
If you install an older (legacy) device that the operating system
cannot recognize, the operating system may have difficulty
assigning resources to it. As a result, a hardware conflict can
occur. To see what resources the operating system has assigned to
the device, see
“Checking device properties” on page 215 .