GS1 EPC Tag Data Standard 1.6 - Indicod-Ecr

39853986398739883989399039913992399339943995399639973998399940004001400240034004400540064007400840094010401140124013401440154016401740184019The overall structure of Packed Objects is described in Section I.3.The individual sections of a Packed Object are described in Sections I.4 through I.9.The structure and features of ID Tables (utilized by Packed Objects to representvarious data system identifiers) are described in Appendix J.The numerical bases and character sets used in Packed Objects are described inAppendix K. An encoding algorithm and worked example are described in Appendix L. The decoding algorithm for Packed Objects is described in Appendix M.In addition, note that all descriptions of specific ID Tables for use with Packed Objectsare registered separately, under the procedures of ISO/IEC 15961-2 as is the completeformal description of the machine-readable format for registered ID Tables.I.3 High-Level Packed Objects Format DesignI.3.1 OverviewThe Packed Objects memory format consists of a sequence in memory of one or more“Packed Objects” data structures. Each Packed Object may contain either encoded dataor directory information, but not both. The first Packed Object in memory is preceded bya DSFID. The DSFID indicates use of Packed Objects as the memory’s Access Method,and indicates the registered Data Format that is the default format for every PackedObject in that memory. Every Packed Object may be optionally preceded or followed bypadding patterns (if needed for alignment on word or block boundaries). In addition, atmost one Packed Object in memory may optionally be preceded by a pointer to aDirectory Packed Object (this pointer may itself be optionally followed by padding).This series of Packed Objects is terminated by optional padding followed by one or morezero-valued octets aligned on byte boundaries. See Figure I 3-1, which shows thissequence when appearing in an RFID tag.NOTE: Because the data structures within an encoded Packed Object are bit-alignedrather than byte-aligned, this Appendix use the term ‘octet’ instead of ‘byte’ except incase where an eight-bit quantity must be aligned on a byte boundary.DSFIDFigure I 3-1: Overall Memory structure when using Packed ObjectsOptionalPointer*And/OrPaddingFirstPackedObjectOptionalPointer*And/OrPaddingOptionalSecondPackedObject…OptionalPackedObjectOptionalPointer*And/OrPaddingZeroOctet(s)*Note: the Optional Pointer to a Directory Packed Object may appear at most only oncein memoryEvery Packed Object represents a sequence of one or more data system Identifiers, eachspecified by reference to an entry within a Base ID Table from a registered data format.The entry is referenced by its relative position within the Base Table; this relativeposition or Base Table index is referred to throughout this specification as an “ID Value.”Copyright ©2005- 2011 GS1 AISBL, All Rights Reserved. Page 164 of 218