Toshiba portйgй m700 series, m705 series Manual De Usuario

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If Something Goes Wrong
Resolving a hardware conflict
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.
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 
The data required by a 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.
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.