Toshiba A55 Manuale Utente

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5.375 x 8.375 ver 2.3

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.

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.

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.

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.

With Plug and Play and the Windows

® 

XP 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