GS1 EPC Tag Data Standard 1.6 - Indicod-Ecr

29582959296029612962296329642965296629672968296929702971Bits Field Contents00 h –0F hCRC CRC code calculated from the remainder of the memory bank.(Normally, this is calculated automatically by the reader, andso software that implements this procedure need not beconcerned with it.)10 h – Length The number of bits, N, in the EPC binary encoding14 h determined in Step 2 above, divided by 16, and rounded up tothe next higher integer if N was not a multiple of 16.15 h UserMemoryIndicator16 h XPCIndicatorThis bit is calculated by the tag and ignored by the tag whenthe tag is written, and so is disregarded by this encodingprocedure.This bit is calculated by the tag and ignored by the tag whenthe tag is written, and so is disregarded by this encodingprocedure.17 h Toggle The value determined in Step 3, above.18 h – AFI /1F h AttributeBitsIf the toggle determined in Step 3 is one, the value of the AFIdetermined in Step 3.2. Otherwise,If the URI includes a control field [att=xNN], the value NNconsidered as an 8-bit hexadecimal number.If the URI does not contain such a control field, zero.20 h – ? EPC / UII The N bits determined in Step 4 above, followed by enoughzero bits to bring the total number of bits to a multiple of 16(0 – 15 extra zero bits)Table 40. Recipe to Fill In Gen 2 EPC Memory Bank from EPC Raw URI15.2Decoding ProceduresThis section specifies how to translate the binary contents of the EPC memory bank of aGen 2 Tag into the EPC Tag URI and EPC Raw URI.15.2.1 Gen 2 EPC Memory Bank into EPC Raw URIGiven:The contents of the EPC Memory Bank of a Gen 2 tagProcedure:1. Extract the length bits, bits 10 h – 14 h . Consider these bits to be an unsigned integer L.2. Calculate N = 16L.3. If bit 17 h is set to one, extract bits 18 h – 1F h and consider them to be an unsignedinteger A. Construct a string consisting of the letter “x”, followed by A as a 2-digithexadecimal numeral (using digits and uppercase letters only), followed by a period(“.”).Copyright ©2005- 2011 GS1 AISBL, All Rights Reserved. Page 114 of 218