Toshiba satellite m110 Manuel D’Utilisation

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5.375 x 8.375 ver 2.3

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. 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.

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.