Creative SB0060 - Sound Blaster Live, Руководство пользователя

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B-6 SB Emulation in MS-DOS/ Windows 95/98
Direct Memory Access
(DMA) Channel
A DMA channel is a data channel that a device uses to transfer data directly to and from the
system memory.
Understanding the
Environment
Variables Environment variables are used to pass hardware configuration information to the software in
your system. For MS-DOS, your audio card includes the following:
❑
CTSYN Environment Variable
❑
BLASTER Environment Variable
CTSYN Environment
Variable
The CTSYN environment variable points to the location of the
CTSYN.INI
file, which usually
resides in the Windows directory. The syntax for this variable is as follows:
CTSYN=path
where path is the location of the
CTSYN.INI
file.
BLASTER Environment
Variable
The BLASTER environment variable specifies the base I/O address, IRQ line, and DMA
channels of the SB interface. Its syntax is:
BLASTER=A220 I5 D1 H5 P330 T6
Table B-3: Possible default direct memory access (DMA) channel assignment.
Usage Default DMA Channel
First DMA channel 0, 1, 3
Second DMA channel 5, 6, 7
4620r-b.fm Page 6 Thursday, April 8, 1999 4:44 PM