Toshiba 2415 Series 用户指南

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页码 279
221
If Something Goes Wrong
Resolving a hardware conflict
5.375 x 8.375 ver 2.4.0
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 may cause a hardware conflict.
NOTE: Some of the IRQs may be shared by multiple devices. This 
is called IRQ sharing and is normal.
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.