NFC Devices WG

Infineon Technologies30.01.2012

• Change Request toType 2 Tag Operation Specification 1.1

• Remove inconsistency of memory size indication versus command set

Problem Statement

• Inconsistency in NFC Forum™ Type 2 Tag Operation Specification 1.1:– Capability Container (CC byte 2) limits memory size

to 2040 byte, see Section 6.1 NDEF Management

– Command set specifies addressing of 254 sectors each 1 Kbyte, see section 5.3 SECTOR SELECT

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Proposed Solution

• Change Request: Remove inconsistency by alignment of memory size indication to memory size yet supported by command

• Split CC byte 2 into “size” and “multiplier”– CC byte 2[6:1]: Size– CC byte 2[8:7]: Multiplier definition

• CC byte 2[8:7] = (00)b: Multiplier = 8• CC byte 2[8:7] = (01)b: Multiplier = 64• CC byte 2[8:7] = (10)b: Multiplier = 512• CC byte 2[8:7] = (11)b: Multiplier = 4096

– Total tag memory size: CC byte 2[6:1] * 8^((CC byte 2[8:7] + 1)

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Technical Aspects

• The maximum memory size covers the capabilities of the command set and offers some more margin

• With CC byte 2[8:7] = (00)b, full backward compatibility is given for tags up to a size of 504 bytes

• Possibly, no 2.x version indication is needed since there are most probably no Type 2 Tags with >504 bytes in the market

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Business Aspects

• Market has yet indicated demand for higher tag memory sizes than 2040 byte, for uses cases like (e.g.)– vCard with photo– Company address with “find us” map– Secured tag contents (by using NFC

Forum™ Signature RTD)

• This change ensures the long-term success of Type 2 Tags

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