108 About Drivers and System Resources
About Drivers and System Resources
This section gives you basic information about drivers and system IRQs.
Drivers
A driver is a program that enables the operating system to work with a hardware
device. Your computer includes drivers for the audio, video, infrared, touchpad,
keyboard, CD-ROM drive, hard drive, floppy drive, and PC Card controller. When
you add a device to your computer, such as a printer, you install a driver for that
device. Different drivers are used by different operating systems.
IRQs
Most of the devices in your computer or connected to your computer need their
own IRQ (interrupt request line). The IRQ is a hardware line that a device can use
to send signals to the microprocessor. When the device needs the microprocessor’s
service, the device sends an interrupt request signal to the microprocessor.
The number of IRQs available for any computer is limited by industry standards.
Because it ships with numerous features, this computer uses most of the available
IRQs. If you add another device to your computer, you may need to disable an
existing device to free up an IRQ for the new device. IRQ resources are of
particular concern when the computer is attached to a docking device.
The default IRQ settings that are used by your computer are listed in Table 10.
Table 10. IRQs
IRQ
Windows 98/ Me
Windows NT 4.0
0
System timer
System timer
1
Keyboard
Keyboard
2
Internal Controller
Internal Controller
3
IrDA Port
COM 2, COM 4
4
COM 1, COM 3
COM 1, COM 3
5
Audio/USB
Audio/USB
