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SB nº 126: Coding and handling of RFU bits and values (Spec Change)

v1.0 Specification Bulletins
Contactless

Specification Bulletin No. 126 First Edition January 2014 Coding and handling of RFU bits and values This Specification Bulletin aligns the requirements related to the coding and handling of RFU bits and values with ISO.

Effective Date

This Specification Bulletin is effective from November 2014 at which time any affected or new type approval testing will come into effect.

Applicability

This Specification Bulletin applies to:  EMV Contactless Specifications for Payment Systems, Book D – EMV Contactless Communication Protocol Specification, Version 2.3.1 – November 2013. Related Documents  None

Description

This Specification Bulletin aligns the requirements related to the coding and handling of RFU bits and values with ISO/IEC 14443.

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Specification Changes 1. Change Requirements 1.1 as follows:

1.7.4 Reserved for Future Use (RFU) Requirements 1.1: RFU PCD and PICC 1.7.4.1 Bytes or bits, specified as Reserved for Future Use (RFU), shall be set to the value indicated, or to zero if no value is given. An entity receiving bytes or bits specified as RFU, shall not examine or depend upon the coding of these bytes or bits.A bit specified as Reserved for Future Use (RFU) shall be set as specified, or to 0b if no indication is given. An entity receiving a bit specified as RFU shall ignore such a bit and shall not change its behaviour, unless explicitly stated otherwise.

1.7.4.2 Values, specified as RFU, shall not be used by the entity sending the data. An entity receiving data with a value specified as RFU, shall treat the value as specified by the related requirement.A data field having a value coded on multiple bits or bytes shall not be set to a value specified as RFU. An entity receiving a data field having a value specified as RFU, shall behave as defined by a requirement that specifically addresses the situation, or shall consider it a protocol error if no specific behaviour is defined.

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2. Change Table 5.3 as follows: Table 5.3: Byte 1 of ATQA b8 b7 b6 b5 b4 b3 b2 b1 Meaning 0 0 UID size: single (4 bytes) 0 1 UID size: double (7 bytes) 1 0 UID size: triple (10 bytes) 1 1 Not allowedRFU 0 RFU 1 0 0 0 0 Bit frame anticollision 0 1 0 0 0 Bit frame anticollision 0 0 1 0 0 Bit frame anticollision 0 0 0 1 0 Bit frame anticollision 0 0 0 0 1 Bit frame anticollision All other values Not allowedRFU 3. Change requirements 5.3 as follows: Requirements 5.3: PCD Handling of ATQA PCD 5.3.2.1 The PCD shall not examine or depend upon thedisregard any values returned by the PICC in b8 to b7 and b5 to b1 of byte 1 and in the least significant nibble b4 to b1 of byte 2 of the ATQA.

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4. Insert a new requirements table for the RFU handling of bit b4 in interface byte TA(1) as follows: Requirements 5.17: PCD Handling of RFU bit b4 in TA(1) PCD 5.7.2.9a A received TA(1) with b4 set to (1)b shall be interpreted by the PCD as if b8 to b1 are set to (00000000)b. 5. Change Table 5.20 as follows: Table 5.20: Coding of Interface Byte TC(1) b8 b7 b6 b5 b4 b3 b2 b1 0 0 0 0 0 0 RFU Meaning 0 RFU 0 RFU 0 RFU 0 RFU 0 RFU 0 RFU x CID supported, if bit is set to (1)b x NAD supported, if bit is set to (1)b 6. Change Table 6.3 as follows: Table 6.3: Coding of PARAM Byte Included in WUPB and REQB Command b8 b7 b6 b5 b4 b3 b2 b1 0 0 0 RFU Meaning 0 RFU 0 RFU 0 RFU x (0)b: Extended ATQB not supported by PCD (1)b: Extended ATQB supported by PCD x (0)b: REQB (1)b: WUPB x x x Number of slots (N)

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7. Insert a new requirements table for the RFU handling of bit b4 in Bit_Rate_Capability as follows: Requirements 6.9: PCD Handling of RFU bit b4 in Bit_Rate_Capability PCD 6.3.2.5a A received Bit_Rate_Capability with b4 set to (1)b shall be interpreted by the PCD as if b8 to b1 are set to (00000000)b. 8. Change Table 6.8 as follows: Table 6.8: Protocol_Type b4 b3 b2 b1 0 RFUMust be set to (0)b Meaning x x Minimum TR2 x PICC compliance with ISO/IEC 14443-4 (see Table 6.9) 9. Change Table 6.13 as follows: Table 6.13: Coding of Param 1 of the ATTRIB command b8 b7 b6 b5 b4 b3 b2 b1 Meaning x x Minimum TR0 x x Minimum TR1 x x Suppression of SoS/EoS 0 RFU 0 RFU 0 0 RFU 10. Change Table 6.19 as follows: Table 6.19: Coding of Param 4 of the ATTRIB Command b8 b7 b6 b5 b4 b3 b2 b1 0 0 0 0 RFU Meaning 0 RFU 0 RFU 0 RFU 0 RFU x x x x CID

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11. Introduce a new table in section 10.1.2 for the coding of b8-b7 of the PCB block as follows: […] The coding of the PCB depends on its type as shown in Table 10.1. Table 10.1: Coding of b8-b7 of PCB b8 b7 0 0 I-block Meaning 0 1 Not allowed 1 0 R-block 1 1 S-block The coding of I-blocks, R-blocks and S-blocks are shown in Table 10.12, Table 10.23 and Table 10.34. […] 12. Change Table 10.1 as follows: Table 10.12: Coding of I-block PCB b8 b7 b6 b5 b4 b3 b2 b1 Meaning 0 0 I-block 0 RFUMust be set to (0)b (1) x Chaining, if bit is set to (1)b 0 CID following, if bit is set to (1)b 0 NAD following, if bit is set to (1)b 1 Must be set to (1)b x Block number (1) Requirement 10.1.5.1 applies when an I-block is received with b6 set to (1)b. Alternatively, legacy PCDs may optionally ignore bit b6. Future versions of this specification may not support this option.

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13. Change Table 10.2 as follows: Table 10.23: Coding of R-block PCB b8 b7 b6 b5 b4 b3 b2 b1 1 0 R-block Meaning 1 Must be set to (1)b x ACK if bit is set to (0)b, NAK if bit is set to (1)b 0 CID following, if bit is set to (1)b 0 1 Must be set to (0)b RFUMust be set to (1)b (1) x Block number (1) Requirement 10.1.5.1 applies when an R-block is received with b2 set to (0)b. Alternatively, legacy PCDs may optionally ignore bit b2. Future versions of this specification may not support this option. 14. Change Table 10.3 as follows: Table 10. 34: Coding of S-block PCB b8 b7 b6 b5 b4 b3 b2 b1 Meaning 1 1 S-block x x If b2 = (0)b, then must be set to (11)b If b2 = (1)b, then (00)b: DESELECT (01)b: Not allowed (10)b: Not allowed (11)b: WTX 0 CID following, if bit is set to (1)b 0 Must be set to (0)b x PARAMETERS if set to (0)b DESELECT or WTX if set to (1)b 0 RFUMust be set to (0)b (1) (1) Requirement 10.1.5.1 applies when an S-block is received with b1 set to (1)b. Alternatively, legacy PCDs may optionally ignore bit b1. Future versions of this specification may not support this option. 15. Renumber Table 10.4 to become Table 10.5 and change the immediately preceding text to: … contains a 1 byte long INF field as specified in Table 10.45.

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16. Change Table 10.5 and the immediately preceding text as follows: … the same WTXM as received in the request (see Table 10.56). Table 10.56: Coding of INF Field of an S(WTX) Response b8 b7 b6 b5 b4 b3 b2 b1 Meaning 0 0 RFUMust be set to (00)b (1) x x x x x x WTXM (1) Requirement 10.1.5.1 applies when an S(WTX) response is received with b8-b7 not set to (00)b. Alternatively, legacy PICCs may optionally ignore bit b8-b7. Future versions of this specification may not support this option. 17. In section 10.3.6, change the references to Table 10.3 to refer to Table 10.4 (two places).

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