NFC Devices WG Change Request to Type 2

NFC Devices WG • Change Request to Type 2 Tag Operation Specification 1. 1 • Remove inconsistency of memory size indication versus command set Infineon Technologies 30. 01. 2012

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 2

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) 3

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 4

Business Aspects • Market has yet indicated demand for higher tag memory sizes than 2040 byte, for uses cases like (e. g. ) – v. Card 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 5