912-3000-035
Revision: 2.1
August 1, 1997
OPTi
82C931
Plug and Play
Integrated Audio Controller
Data Book
OPTi Inc.
888 Tasman Drive
Milpitas, CA 95035
Tel: (408) 486-8000
Fax: (408) 486-8001
WWW: http://www.opti.com/
Copyright
Copyright 1996, OPTi Inc. All rights reserved. No part of this publication may be reproduced, transmitted, tran-
scribed, stored in a retrieval system, or translated into any language or computer language, in any form or by any
means, electronic, mechanical, magnetic, optical, chemical, manual, or otherwise, without the prior written permis-
sion of OPTi Incorporated, 888 Tasman Drive, Milpitas, CA 95035.
Disclaimer
OPTi Inc. makes no representations or warranties with respect to the design and documentation herein described
and especially disclaims any implied warranties of merchantability or fitness for any particular purpose. Further,
OPTi Inc. reserves the right to revise the design and associated documentation and to make changes from time to
time in the content without obligation of OPTi Inc. to notify any person of such revisions or changes.
Trademarks
OPTi and OPTi Inc. are registered trademarks of OPTi Incorporated.
All other trademarks and copyrights are the property of their respective holders.
82C931
Table of Contents
OPTi
912-3000-035
Page iii
Revision: 2.1
1.0
Features ............................................................................................................................ 1
2.0
Overview ........................................................................................................................... 3
3.0
Signal Definitions ............................................................................................................. 5
3.1
Mode Selection ................................................................................................................................... 5
3.2
931-MB Mode....................................................................................................................................... 6
3.2.1
931-MB Mode Signal Descriptions ......................................................................................... 8
3.2.1.1
ISA Bus Interface Signals ....................................................................................... 8
3.2.1.2
MIDI Interface Signals............................................................................................. 8
3.2.1.3
Configuration and External PnP EEPROM Interface Signals ................................. 9
3.2.1.4
Game Port and Serial Audio Interface Signals ....................................................... 9
3.2.1.5
Codec/Mixer Interface Signals ..............................................................................10
3.2.1.6
Power and Ground Pins ........................................................................................11
3.3
931-AD Mode .....................................................................................................................................12
3.3.1
931-AD Mode Signal Descriptions........................................................................................14
3.3.1.1
ISA Bus Signals ....................................................................................................14
3.3.1.2
MIDI Interface Signals...........................................................................................14
3.3.1.3
Configuration, External PnP EEPROM, and IDE CD-ROM Interface Signals.......15
3.3.1.4
Game Port and Modem Interface Signals .............................................................16
3.3.1.5
Codec/Mixer Interface Signals ..............................................................................16
3.3.1.6
Serial Audio Interface Signals ...............................................................................17
3.3.1.7
Power and Ground Pins ........................................................................................17
4.0
Functional Description .................................................................................................. 19
4.1
Plug and Play ....................................................................................................................................19
4.2
16-Bit Codec/Mixer ...........................................................................................................................20
4.2.1
Codec ...................................................................................................................................20
4.2.2
Mixer.....................................................................................................................................21
4.3
Frequency Synthesizer ....................................................................................................................22
4.4
16-Bit Type F DMA Playback ...........................................................................................................23
4.5
Modem Interface ...............................................................................................................................23
4.6
Push Button Volume Control...........................................................................................................23
4.7
External Serial EEPROM ..................................................................................................................23
4.8
Serial Audio Interface .......................................................................................................................23
4.8.1
I2S-justified format and its variations....................................................................................23
4.8.2
Sony format ..........................................................................................................................24
82C931
OPTi
Table of Contents (cont.)
Page iv
912-3000-035
Revision: 2.1
4.8.3
AT&T PCM codec T7525 compatible 16-bit mono format ....................................................24
4.8.4
Testing I2S format (ZV port) with Audio Precision machine .................................................24
4.8.5
Relevant MC register settings ..............................................................................................24
4.8.6
ZV-Port I2S...........................................................................................................................25
4.8.6.1
LRCLK ..................................................................................................................25
4.8.6.2
SDATA ..................................................................................................................25
4.8.6.3
SCLK.....................................................................................................................26
4.8.6.4
MCLK ....................................................................................................................26
4.8.7
Advanced Precision General Purpose Serial Port................................................................26
4.8.8
TDA1311 Stereo Continuous Calibration .............................................................................27
5.0
Register Descriptions .................................................................................................... 29
5.1
I/O Base Addresses ..........................................................................................................................29
5.2
MCBase Register .............................................................................................................................29
5.3
SBBase Register ...............................................................................................................................36
5.4
WSBase Register ..............................................................................................................................37
6.0
Electrical Specifications................................................................................................ 45
6.1
Absolute Maximum Ratings.............................................................................................................45
6.2
DC Characteristics: 5.0 Volt (VCC = 5.0V 5%, TA = 0C to +70C)..............................................45
6.3
General Specifications: 5.0 Volt (VCC = 5.0V 5%, TA = 0C to +70C) .......................................46
6.4
Pin Specifications - Analog (VCC = 5.0V, 25C) ............................................................................47
6.5
Volume Setting..................................................................................................................................47
6.6
Analog Characteristics.....................................................................................................................47
6.6.1
Analog Inputs........................................................................................................................48
6.6.2
Analog Outputs (10kW, 25pF) ..............................................................................................48
6.6.3
Volume Settings ...................................................................................................................48
6.6.4
Analog-to-Digital Converters ................................................................................................49
6.6.5
Digital-to-Analog Converters ................................................................................................49
6.7
AC Timings ........................................................................................................................................49
7.0
Mechanical Packages .................................................................................................... 53
82C931
List of Figures
OPTi
912-3000-035
Page v
Revision: 2.1
Figure 1-1
System Block Diagram .................................................................................................................... 1
Figure 2-1
Functional Block Diagram................................................................................................................ 3
Figure 2-2
Data Flow Block Diagram ................................................................................................................ 4
Figure 3-1
931-MB Mode PQFP Pin Diagram.................................................................................................. 6
Figure 3-2
931-AD Mode PQFP Pin Diagram .................................................................................................12
Figure 4-1
Functional Block Diagram..............................................................................................................20
Figure 4-2
Mixer Block Diagram .....................................................................................................................21
Figure 4-3
I2S Format .....................................................................................................................................25
Figure 4-4
General Purpose Serial Port, Timing Relationships ......................................................................26
Figure 4-5
Format of Input Signals .................................................................................................................27
Figure 6-1
RESET and CLK Timing Waveform...............................................................................................50
Figure 6-2
CD-ROM I/O Read Cycle...............................................................................................................51
Figure 6-3
CD-ROM I/O Write Cycle...............................................................................................................51
Figure 6-4
DMA Write/Playback Cycle............................................................................................................52
Figure 6-5
DMA Read/Capture Cycle .............................................................................................................52
Figure 7-1
100-pin PQFP, Plastic Quad Flat Pack .........................................................................................53
Figure 7-2
100-pin TQFP, Thin Quad Flat Package .......................................................................................54
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