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1、S SMMB Bu us s C Co on nt tr ro ol l MMe et th ho od d I In nt te er rf fa ac ce e S Sp pe ec ci if fi ic ca at ti io on n Version 1 0 December 10 1999 Copyright 1999 Duracell Inc Energizer Power Systems Fujitsu Personal Systems Inc Intel Corporation Linear Technology Corporation Maxim Integrated Pr
2、oducts Mitsubishi Electric Corporation PowerSmart Inc Toshiba Battery Co Unitrode Benchmarq USAR Systems All rights reserved ii Questions and comments regarding this specification may be forwarded to smbus sbs forum org For additional information on SMBus Specification visit the SBS IF at http www s
3、bs forum org smbus THIS SPECIFICATION OR THE SAMPLE CODE PROVIDED HEREWITH OR REFERENCED HEREIN IS PROVIDED AS IS WITH NO WARRANTIES WHATSOEVER INCLUDING ANY WARRANTY OF MERCHANTABILITY NONINFRINGEMENT FITNESS FOR ANY PARTICULAR PURPOSE OR ANY WARRANTY OTHERWISE ARISING OUT OF ANY PROPOSAL SPECIFICA
4、TION OR SAMPLE IN NO EVENT SHALL ANY OF THE CO OWNERS BE LIABLE FOR ANY DAMAGES WHATSOEVER INCLUDING WITHOUT LIMITATION DAMAGES FOR LOSS OF PROFITS BUSINESS INTERRUPTION LOSS OF INFORMATION ARISING OUT OF THE USE OF INFORMATION OR THE SAMPLE CODE PROVIDED HEREWITH OR REFERENCED HEREIN THE AUTHORS DI
5、SCLAIM ALL LIABILITY INCLUDING LIABILITY FOR INFRINGEMENT OF ANY PROPRIETARY RIGHTS RELATING TO USE OF INFORMATION IN THIS SPECIFICATION NO LICENSE EXPRESS OR IMPLIED BY ESTOPPEL OR OTHERWISE TO ANY INTELLECTUAL PROPERTY RIGHTS IS GRANTED HEREIN IN NO EVENT WILL ANY SPECIFICATION CO OWNER BE LIABLE
6、TO ANY OTHER PARTY FOR ANY LOSS OF PROFITS LOSS OF USE INCIDENTAL CONSEQUENTIAL INDIRECT OR SPECIAL DAMAGES ARISING OUT OF THIS SPECIFICATION OR THE SAMPLE CODE PROVIDED HEREWITH OR REFERENCED HEREIN WHETHER OR NOT SUCH PARTY HAD ADVANCE NOTICE OF THE POSSIBILITY OF SUCH DAMAGES FURTHER NO WARRANTY
7、OR REPRESENTATION IS MADE OR IMPLIED RELATIVE TO FREEDOM FROM INFRINGEMENT OF ANY THIRD PARTY PATENTS WHEN USING THE INFORMATION OR SAMPLE CODE PROVIDED HEREWITH OR REFERENCED HEREIN Third party brands and names are the property of their respective owners Document Revision History RevisionDateAuthor
8、Reason for Changes Rev 1 010 Dec 1999SBS IFInitial release System Management Bus SMBus Control Method Interface Specification Version 1 0 Page iii Table of Contents 1Introduction 1 1 1Target Audience 1 1 2Related Documents 1 1 3Data Format 1 1 4Terminology 1 2Overview 3 2 1Goals 3 2 2Problem Stateme
9、nt 3 2 3Solution 3 2 3 1SMBus CMI Objects 4 2 3 2Namespace Hierarchy 5 2 4Hardware Alerting 5 2 5Packet Error Checking 5 3SMBus CMI Objects 6 3 1Overview 6 3 2ASL Definition 6 3 2 1Requirements 6 3 2 2Name 7 3 2 3Device Identification 7 3 3Control Methods 7 3 3 1SMBus Information SBI 8 3 3 2SMBus Da
10、ta Read SBR 8 3 3 3SMBus Data Write SBW 9 3 3 4SMBus Data Transfer SBT 9 3 3 5SMBus Alert Information SBA 10 3 4Protocol Mappings 10 3 4 1 SBR Protocols 10 3 4 2 SBW Protocols 11 3 4 3 SBT Protocols 11 3 5Data Structures 12 3 5 1SMB INFO 12 3 5 2SMB DEVICE 13 Appendix A Data Types 16 A 1Data Format
11、16 A 2Device Addressing 16 A 3Bus Protocols 16 A 4Status Codes 17 Appendix B Sample ASL 19 B 1Mobile Example 19 B 1 1ASL Overview 19 B 1 2EC SMBus Sample ASL 20 B 2Desktop Example 32 B 2 1ASL Overview 32 B 2 2PIIX4 SMBus Sample ASL 32 System Management Bus SMBus Control Method Interface Specificatio
12、n Version 1 0 Page iv List of Tables Table 1 SBR Protocol Mapping 10 Table 2 SBW Protocol Mapping 11 Table 3 SBT Protocol Mapping 11 Table 4 Protocol Values 17 Table 5 Status Code Values 18 List of Figures Figure 1 SMBus CMI Architecture 4 Figure 2 Example ACPI Namespace Hierarchy 5 Figure 3 Data Fo
13、rmat 16 Figure 4 Slave Address Encoding 16 Figure 5 Protocol Encoding 17 Figure 6 Status Code Encoding 17 Figure 7 Mobile Example System 19 Figure 8 Desktop Example System 32 System Management Bus SMBus Control Method Interface Specification Version 1 0 Page 1 1 Introduction This specification defin
14、es a System Management Bus SMBus interface for Advanced Configuration and Power Interface ACPI This interface referred to as the SMBus Control Method Interface CMI allows the capabilities of an SMBus segment to be easily utilized regardless of hardware origin or implementation This document s scope
15、is limited to the definition and use of the SMBus CMI The appendix provides sample ACPI Source Language ASL code illustrating how to implement this interface for several example systems 1 1 Target Audience This specification is intended for use by the following audience OEMs and ISVs developing plat
16、form firmware OEMs and IHVs developing SMBus devices Others interested in accessing SMBus devices in the ACPI environment Basic understanding of ACPI and the SMBus is assumed 1 2 Related Documents 1 Advanced Configuration and Power Interface Specification v1 0b 1996 1997 1998 Intel Corporation Microsoft Corporation Toshiba Corporation This specification and other ACPI documentation are available at 2 System Management Bus Specification Revision 1 1 SBS Implementers Forum December 1998 This speci