Interrupt Request (IRQ) Lines

An IRQ line is a signal line a device uses to notify your computer’s central processor that it wants to send or receive data for processing.

Table B-2lists an example of an IRQ line that may be assigned to the audio interface on your audio card.

Table B-2: Possible default IRQ line assignments.

IRQ Line

Device

 

 

5 Audio interface

Direct Memory Access (DMA) Channels

A DMA channel is a data channel a device uses to transfer data directly to and from the system memory. Your card’s audio interface transfers data through the Low and High DMA channels.

Table B-3shows a possible combination of DMA channels that may be assigned to the audio interface.

Table B-3: Possible default DMA channel assignments.

DMA ChannelUsage

 

 

1

Audio Low DMA channel

 

 

5

Audio High DMA channel

 

 

Understanding the Environment Variables

Environment variables are used to pass information about how your card is configured to programs in your system. This section explains the environment variables of your audio card:

❑SOUND Environment Variable

❑BLASTER Environment Variable

❑MIDI Environment Variable

Understanding the Installation B-3