GS1 EPC Tag Data Standard 1.6 - Indicod-Ecr

3049305030513052305330543055305630573058305930603061306230633064306530663067306830693070307130723073307430753076307730783079308030813082according to the registration authority defined by this class identifier value and shallcontain, at a minimum, sufficient identifying information for an Interrogator to uniquelyidentify the custom commands and/or optional features that a Tag supports.” For theallocation class identifier of E2 h this information is the MDID and TMN, regardless ofwhether the extended TID is present or not. If two tags differ in custom commandsand/or optional features, they must be assigned different MDID/TMN combinations. Inparticular, if two tags contain an extended TID and the values in their respective extendedTIDs differ in any value other than the value of the serial number, they must be assigneda different MDID/TMN combination. (The serial number by definition must be differentfor any two tags having the same MDID and TMN, so that the Serialized TagIdentification specified in Section 16.3 is globally unique.) For tags that do not containan extended TID, it should be possible in principle to use the MDID and TMN to look upthe same information that would be encoded in the extended TID were it actually presenton the tag, and so again a different MDID/TMN combination must be used if two tagsdiffer in the capabilities as they would be described by the extended TID, were it actuallypresent.16.1Short Tag IdentificationIf the XTID bit (bit 08 h of the TID bank) is set to zero, the TID bank only contains theallocation class identifier, mask designer identifier (MDID), and Tag model number(TMN) as specified above. Readers and applications that are not configured to handle theextended TID will treat all TIDs as short tag identification, regardless of whether theXTID bit is zero or one.Note: The memory maps depicted in this document are identical to how they are depictedin [UHFC1G2]. The lowest word address starts at the bottom of the map and increasesas you go up the map. The bit address reads from left to right starting with bit zero andending with bit fifteen. The fields (MDID, TMN, etc) described in the document put theirmost significant bit (highest bit number) into the lowest bit address in memory and theleast significant bit (bit zero) into the highest bit address in memory. Take the ISO/IEC15963 allocation class identifier of E2 h = 11100010 2 as an example. The most significantbit of this field is a one and it resides at address 00 h of the TID memory bank. The leastsignificant bit value is a zero and it resides at address 07 h of the TID memory bank.When tags backscatter data in response to a read command they transmit each wordstarting from bit address zero and ending with bit address fifteen.TID MEMBANK BITADDRESSBIT ADDRESS WITHIN WORD (In Hexadecimal)0 1 2 3 4 5 6 7 8 9 A B C D E F10 h -1F h TAG MDID[3:0] TAG MODEL NUMBER[11:0]00 h -0F h E2 h TAG MDID[11:4]3083Table 41. Short TID formatCopyright ©2005- 2011 GS1 AISBL, All Rights Reserved. Page 117 of 218