Toshiba 1805 Manual De Usuario

204

If Something Goes Wrong
Resolving a hardware conflict

The smooth operation of the system depends on the interaction of 
all devices, programs, and features. If the system or one of its 
attached devices isn’t working, resolving the problem can be time- 
consuming and frustrating.

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 CD-ROM 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.

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