GS1 EPC Tag Data Standard 1.6 - Indicod-Ecr

4711471247134714471547164717471847194720472147224723472447254726472747284729473047314732473347344735473647374738Directory IDMPO’s ID Map section contains additional optional subsections. Thestructure of an ID Map section, containing one or more ID Maps, is described in sectionI.9.1, explained in terms of its usage in a Data IDMPO; subsequent sections explain theadded structural elements in a Directory IDMPO.I.9.1 ID Map Section structureAn IDMPO represents ID Values using a structure called an ID Map section, containingone or more ID Maps. Each ID Value encoded in a Data IDMPO is represented as a ‘1’bit within an ID Map bit field, whose fixed length is equal to the number of entries in thecorresponding Base Table. Conversely, each ‘0’ in the ID Map Field indicates theabsence of the corresponding ID Value. Since the total number of ‘1’ bits within the IDMap Field equals the number of ID Values being represented, no explicit NumberOfIDsfield is encoded. In order to implement the range of functionality made possible by thisrepresentation, the ID Map Section contains elements other than the ID Map itself. Ifpresent, the optional ID Map Section immediately follows the leading pattern indicatingan IDMPO (as was described in I.4.2), and contains the following elements in the orderlisted below: An Application Indicator subsection (see I.5.3.1) an ID Map bit field (whose length is determined from the ID Size in the ApplicationIndicator) a Full/Restricted Use bit (see I.5.3.2) (the above sequence forms an ID Map, which may optionally repeat multiple times) a Data/Directory indicator bit, an optional AuxMap section (never present in a Data IDMPO), and Closing Flag(s), consisting of an “Addendum Flag” bit. If ‘1’, then an Addendumsubsection is present at the end of the Object Info section (after the Object LengthInformation).These elements, shown in Figure I 9-1 as a maximum structure (every element ispresent), are described in each of the next subsections.4739Figure I 9-1: ID Map sectionFirst ID MapAppIndicatorIDMapBitField(endswithF/Rbit)Optional additionalID Map(s)AppIndicatorID MapField(endswithF/R bit)Null AppIndicator(singlezero bit)Data/DirectoryIndicatorBit(Ifdirectory)OptionalAuxMapSectionClosingFlag Bit(s)SeeSeeI.9.1.1As As See SeeFigure I 9-AddendumCopyright ©2005- 2011 GS1 AISBL, All Rights Reserved. Page 185 of 218