82C931 Datasheet, PDF (13/64 Pages) List of Unclassifed Manufacturers – Plug and Play Integrated Audio Controller

82C931
3.0 Signal Definitions
3.1 Mode Selection
The 82C931 can be configured into two different modes:
• 931-MB Mode
- Single-chip motherboard application with 16-bit DMA
support to enhance telephony-audio application perfor-
mance.
• 931-AD Mode
- Single chip adaptor card with support for IDE CD-ROM
and modem interfaces.
Pins 11 is used to select the desired mode of the 82C931 (as
shown in Table 3-1). Table 3-2 details the features in both of
these modes.
Table 3-1 Mode Selection
Pin 11
1
0
Mode
931-MB
931-AD
Table 3-2 Mode Features
Feature
931-MB
931-AD⁽⁴⁾
IDE CD Interface
IDE Interrupt Redirect
Modem Interface
Volume Control
Serial Audio Port
Internal OPTiFM
16-Bit DMA
No
No
No
Yes⁽²⁾
Yes⁽³⁾
Yes
Yes
Yes
Yes
Yes⁽¹⁾
Yes⁽²⁾
Yes
Yes
No
1. Pins are shared between second Game Port and Modem
interface.
2. Volume Control can be used when second Game Port is
not used by others.
3. Pins are shared between second Game Port and Serial
Audio port.
4. The IDE and modem resources are programmable in
931-AD mode (available in 931 silicon revision 1.1 only).
Some pins of the 82C931 take on different functions depend-
ing upon its configured mode. The following subsections give
the pin assignment and definitions for both the 931-MB and
931-AD modes, respectively.
In addition to mode defined pins, the 82C931 has multiplexed
pins. These pins are denoted with a plus (+) sign between
signal names. Their definitions can also be found in the signal
description tables.
Table 3-3 defines abbreviated terms that are used throughout
this section.
Table 3-3
Mnemonic
Analog
CMOS
Ext
G
I
Int
I/O
Mux
O
OD
P
PD
PU
Smt
TS
TTL
Signal Definitions Legend
Description
Analog-level compatible
CMOS-level compatible
External
Ground
Input
Internal
Input/Output
Multiplexer
Output
Open drain
Power
Pull-down resistor
Pull-up resistor
Schmitt-trigger
Tristate
TTL-level compatible
912-3000-035
Revision: 2.1
OPTi
®
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