Toshiba M200 Manuale Utente

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If Something Goes Wrong
Resolving a hardware conflict
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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 
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 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. Plug in the device and turn on your 
computer. The operating system is automatically set up to 
accommodate the new device.