IBM PC 300GL Types 6275, Информационное руководство

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Expansion-Bus Slots
If you want to add new capabilities to your computer, you can do so by installing optional
adapters. Your computer provides an ISA-bus expansion slot so you can take advantage of
the wide availability of ISA peripheral devices and applications. Also, PCI-bus expansion
slots allow you to connect high-performance devices to your computer, such as graphics,
SCSI, or LAN adapters.
There are four expansion slots in your computer. Three are dedicated PCI slots and one is a
dedicated ISA slot. These slots are grouped together on the system board.
The width of the expansion-bus determines the type of adapters the computer supports.
The dedicated ISA slots accept only 8-bit or 16-bit ISA adapters, and the dedicated PCI slots
accept only 32-bit PCI adapters. The width of the bus does not affect software
compatibility.
Adapter Configuration
When adding adapters, you might need to manually set a variety of switches on the
adapters. These switches control the assignment of computer resources such as interrupt
request (IRQ) lines, direct memory access (DMA) channels, and memory address ranges.
Determining how to set switches for (or configuring) these resources can be complex. A
better method of configuring adapters and devices called Plug and Play is used on your
computer to make expansion an easier task.
Plug and Play Adapters
Plug and Play is a configuration method that makes expanding your computer easier. Plug
and Play adapters are easier to set up because they are auto-configuring. A Plug and Play
adapter comes with built-in identification and configuration specifications set in memory on
the adapter to provide installation information to the computer during startup. This
information is interpreted by the computer's basic input/output system (BIOS), which supports
Plug and Play. The BIOS routines automatically configure the adapter as long as the
required resources are not already in use.
Adapters designed for PCI slots are Plug and Play devices. Many adapters designed for
ISA slots are not Plug and Play devices. If the adapter you are installing is not Plug and
Play, you must configure it manually.
10 Expansion-Bus