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SB nº 123: Alignment 3 (Spec Change)

v1.0 Specification Bulletins
Contactless

Specification Bulletin No. 123 First Edition January 2014 Alignment 3 This Specification Bulletin aligns a number of parameters and functional behaviour with ISO/IEC 14443 and NFC Forum Digital Protocol Specifications in addition to previously published alignment bulletins.

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 a number of parameters and functional behaviour with ISO/IEC 14443 and NFC Forum Digital Protocol Specification.

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Specification Changes 1. In Section 1.6 Definitions, change the definition of Transmission Error as follows: Transmission error An invalid frame is received detected by the receiver: In this case Failure of a parity or CRC check, or determination that any of the signal modulation, the bit coding, the frame format, or the timing is are not consistent with this specification (Chapters 3 and 4). 2. In Section 1.7.1 Abbreviations, add a new row to Table 1.1 as follows: Abbreviation … EGT EMD EoF … Description Extra Guard Time, Type B Electromagnetic Disturbance End of Frame 3. In Annex A.4 Sequences and Frames, change FWT as follows: Topic Common Table A.5: Sequences and Frames Parameter … FWT … PCD Value Min Max 384 x 2FWI 49152 PICC Value Min Max Units 1/fc

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4. Insert new Section 4.9: EMD Handling as described below. Delete the description of tnn,min from section 4.8.1 and move it into the new section 4.9 EMD Handling. Renumber requirements tables 4.27 and 4.28 to 4.26 and 4.27 respectively.

4.9 EMD Handling EMD Handling enhances the robustness of the contactless communication between PCD and PICC against PICC generated electromagnetic disturbance (EMD). 4.9.1 tnn,min The time tnn,min is the minimum period during which the PICC is not allowed to produce any detectable disturbance before sending its response. […] PICC Requirements 4.28: tnn,min 4.89.1.16 The PICC shall not produce any detectable disturbance during a period of at least tnn,min before sending its response. The exact quantity of what constitutes ‘any detectable disturbance’ is not defined by this version of the specification. Note: This was previously requirement number 4.8.1.16.

4.9.2 PCD EMD Handling It is important for a PCD to distinguish between EMD and frame reception errors and therefore the following PCD EMD Handling applies. PCD 4.9.2.1 Requirements 4.29: PCD EMD Handling When the PCD receives a PICC frame it shall check for transmission errors. If a transmission error is detected and the number of received bytes is less than 4, then the PCD shall ignore the transmission and be ready to receive a PICC frame within a time tRECOVERY after the end of the modulation of the received bytes with the transmission error. This does not apply to responses to the WUPA, REQA, SELECT, ANTICOLLISION, WUPB and REQB commands. Refer to Annex A.4 for the value of tRECOVERY.

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The above defined EMD handling overrules the specified transmission error handling in cases where a transmission error is detected when less than 4 bytes have been received from the PICC. 5. Change Requirements 4.5 as follows: Requirements 4.5: Loaded State PCD If the PCD senses the carrier modulated for the first half of the bit duration and the bit period does not start with the loaded state of the subcarrier, then the PCD may resort to exception processing (transmission error). Note that the transmission error is suppressed by the EMD handling defined in section 4.9.2 if the transmission error is detected when less than 4 bytes have been received from the PICC. PICC 4.4.2.1 If the carrier is modulated with the subcarrier for the first half of the bit duration (symbol D), then the bit period shall start with the loaded state of the subcarrier (see Figure 4.7).

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Change requirement 9.6.1.1 as follows: Requirements 9.10: Exception Processing PCD 9.6.1.1 During the activation procedure, on detection of a response with a transmission error, the PCD shall report the transmission error to the terminal, reset the Operating Field (as defined in section 3.2.6), and return to the polling procedure. if all of the following are true:  The response is encapsulated in a frame of at least 4 characters.  The response is encapsulated in a frame without residual bits (i.e. number of data bits is a multiple of 8).  The response contains a CRC and the CRC is incorrect or the response is encapsulated in a frame with a parity error. The PCD shall ignore all other transmission errors and shall be ready to process a correct response within a time tRECOVERY after the end of the response with the transmission error. The PCD shall start the reset of the PICC within a delay tRESETDELAY measured from the start of the invalid response. A flowchart illustrating the processing specified above is included in Annex D. Note that the transmission error is suppressed by the EMD handling defined in section 4.9.2 if the transmission error is detected when less than 4 bytes have been received from the PICC.

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Change requirement 10.3.5.3 as follows: Requirements 10.13: Exception Processing – PCD PCD 10.3.5.3 If a block with a transmission error is received after receipt of a block not indicating chaining, then the PCD shall send an R(NAK) block. if all of the following are true:  The block is encapsulated in a frame of at least 4 characters long.  The block is encapsulated in a frame without residual bits (i.e. the number of data bits is a multiple of 8).  The CRC is incorrect or the frame has a parity error. The PCD shall ignore all other transmission errors and shall be ready to process a correct block within a time tRECOVERY after the end of the block with the transmission error. The PCD shall send the R(NAK) block within a time tRETRANSMISSION measured from the start of the block with the transmission error. The PCD shall send up to two consecutive R(NAK) blocks to ask for retransmission. If a block with a transmission error in response to the second R(NAK) block is received, then the PCD shall report a transmission error to the terminal and continue as specified in 10.3.5.9 within a time tRESETDELAY measured from the start of the last invalid response. Note that the transmission error is suppressed by the EMD handling defined in section 4.9.2 if the transmission error is detected when less than 4 bytes have been received from the PICC.

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Change requirement 10.3.5.6 as follows: Requirements 10.13: Exception Processing – PCD PCD 10.3.5.6 If a block with a transmission error is received after receipt of a block indicating chaining, then the last R(ACK) block sent by the PCD shall be retransmitted. if all of the following are true:  The block is encapsulated in a frame of at least 4 characters long.  The block is encapsulated in a frame without residual bits (i.e. the number of data bits is a multiple of 8).  The CRC is incorrect or the frame has a parity error. The PCD shall ignore all other transmission errors and shall be ready to process a correct frame within a time tRECOVERY after the end of the block with the transmission error. The PCD shall send the R(ACK) block within a time tRETRANSMISSION measured from the start of the block with the transmission error. The PCD shall retransmit the R(ACK) block up to two consecutive times to ask for retransmission. If a block with a transmission error in response to the second R(ACK) block is received, then the PCD shall report a transmission error to the terminal and continue as specified in 10.3.5.9 within a time tRESETDELAY measured from the start of the last invalid response. Note that the transmission error is suppressed by the EMD handling defined in section 4.9.2 if the transmission error is detected when less than 4 bytes have been received from the PICC.

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6. Delete Annex D. 7. Delete references to Annex D.  In Section 2.5 Overview: Annex D contains a flowchart clarifying the PCD exception processing specified in Chapter 9 and Chapter 10.  In Section 10.3.5 Exception Processing: PCD exception processing aims to distinguish between any detectable disturbance in the Operating Field appearing before the response from the PICC and a real response with transmission error from the PICC. A flowchart illustrating the processing specified below is included in Annex D. 8. In Section 10.3.2 Chaining, add a clarification that requirement 10.3.2.1 also applies to empty I-blocks. Requirements 10.7: Chaining Rules PCD and PICC 10.3.2.1 The chaining bit in the PCB of an I‐block controls the chaining of blocks. When an I‐block indicating chaining is received, the block shall be acknowledged by an R(ACK) block. This requirement applies even if the INF field of the received I‐block has zero length.

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9. In Section 10.3.2 Chaining, add a requirement that a PICC must not send an empty I-block indicating chaining. PCD … Requirements 10.8: Block Sizes during Chaining PICC … 10.3.2.4 When the PICC sends a chain of I‐blocks, each block indicating chaining (i.e. all blocks of the chain except the last one) shall have an INF field with a length different from zero. 10. In Section 10.3.4 Block Handling Rules, add an informative statement to requirement 10.3.4.8. Requirements 10.12: Block Handling Rules for the PICC PICC … 10.3.4.8 When an I‐block not indicating chaining is received, the block shall be acknowledged by an I‐block. If the I‐block received has a zero length INF field then the mandatory I‐ block sent may either have a zero length INF field or may contain any applicative information. …

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11. In Requirements 4.23 introduce TPCD as follows: Requirements 4.23: Frame Waiting Time PCD PICC 4.8.1.8 The PCD shall wait at least FWT + FWT for a response from the PICC (except for WUPA, REQA, SELECT, ANTICOLLISION, RATS, WUPB, and REQB). If the PCD does not receive a response from the PICC within FWT + FWT + TPCD, then the PCD shall consider this is as a time‐out error. Refer to Annex A.4 for the values of TPCD and FWT. Between FWT + ΔFWT and FWT + ΔFWT + ΔTPCD, the PCD may accept the response of the PICC or may generate a time‐out error.

4.8.1.9 The PICC shall start its response after the end of a PCD command within the FWT (except for WUPA, REQA, SELECT, ANTICOLLISION, RATS, WUPB, and REQB).

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12. In Requirements 4.24 introduce TPCD as follows: PCD Requirements 4.24: Activation Frame Waiting Time PICC 4.8.1.12 For the Type A – RATS command, the PCD shall wait at least FWTACTIVATION for a response from the PICC. If the PCD does not receive a response from the PICC within FWTACTIVATION + TPCD, then the PCD shall consider this is as a time‐out error. Refer to Annex A.4 for the value of TPCD. Between FWTACTIVATION and FWTACTIVATION + ΔTPCD, the PCD may accept the response of the PICC or may generate a time‐out error.

4.8.1.13 For the Type A – RATS command, the PICC shall start its response within FWTACTIVATION. Refer to Annex A.4 for the value of FWTACTIVATION.

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13. In Requirements 4.25 introduce TPCD as follows: Requirements 4.25: FWTATQB and TR0MAX for WUPB and REQB Commands PCD 4.8.1.14 For the Type B – WUPB and REQB commands, the PCD shall wait at least FWTATQB for a response from the PICC. If the PCD does not receive a response from the PICC within FWTATQB + TPCD, then the PCD shall consider this is as a time‐out error. Refer to Annex A.4 for the values of FWTATQB and TPCD. Between FWTATQB and FWTATQB + ΔTPCD, the PCD may accept the response of the PICC or may generate a time‐out error. If the PCD does not detect the start of the subcarrier from the PICC before TR0MAX,ATQB, then the PCD may consider this is as a time‐out error. PICC 4.8.1.15 For the Type B – WUPB and REQB commands, the PICC shall start the unmodulated subcarrier within TR0MAX,ATQB. Refer to Annex A.4 for the value of TR0MAX,ATQB.

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In Annex A.4 Sequences and Frames, change the PCD Value for FWTATQB and add the PCD Value for TR0MAX,ATQB as follows: Topic Type B Table A.5: Sequences and Frames Parameter … TR0MAX,ATQB … PCD Value Min Max 6416 PICC Value Min Max 4096 Units 1/fc Note that SB122 already introduced the changes for the PICC.

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14. In Requirements 10.5 introduce TPCD as follows: Requirements 10.5: Frame Waiting Time Extension PCD … 10.2.2.7 After sending the S(WTX) response block in response to an S(WTX) request block from the PICC, the PCD shall wait for at least FWTTEMP + (FWT x WTXM) for a block of the PICC. If the PCD does not receive a block from the PICC within FWTTEMP + (FWT x WTXM) + TPCD, then the PCD shall resort to exception processing (time‐out error). Refer to Annex A.4 for the value of TPCD. Between FWTTEMP + FWT and FWTTEMP + FWT + TPCD, the PCD may accept the response of the PICC or may generate a time‐out error. PICC 10.2.2.8 After receiving the S(WTX) response block of the PCD, the PICC shall start sending the next block within FWTTEMP. … 10.2.2.9 The PCD shall apply FWTTEMP + (FWT x WTXM) only until the next block has been received from the PICC or until the PCD resorts to exception processing. …

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15. Change Requirements 10.3.5.5 and 10.3.5.8 to fix FWT as follows: PCD … 10.3.5.5 If a time‐out error occurs after receipt of a block not indicating chaining, then:  Up to two R(NAK) blocks shall be sent to ask for retransmission.  The PCD shall send the R(NAK) block after tTIMEOUT and before tTIMEOUT + tRETRANSMISSION. If a time‐out error occurs after the second R(NAK) block, or if the PCD has detected a time‐out after having re‐ transmitted an S(WTX) response block two times (i.e. the PCD twice consecutively repeats the sequence of detecting a time‐out error following an S(WTX) response block, sending R(NAK) block(s), receiving an S(WTX) request, and sending the S(WTX) response), then the PCD shall report a time‐out error to the terminal and continue as specified in requirement 10.3.5.9 within tTIMEOUT and tTIMEOUT + tRESETDELAY. If no frame waiting time extension is requested by the PICC, then tTIMEOUT is equal to FWT + FWT. Otherwise, tTIMEOUT is equal to (FWT x WTXM) + FWT.

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PCD 10.3.5.8 If a time‐out error occurs after receipt of a block indicating chaining:  The last R(ACK) block sent by the PCD shall be retransmitted up to two times to ask for retransmission.  The PCD shall send the R(ACK) block after tTIMEOUT and before tTIMEOUT + tRETRANSMISSION. If a time‐out error occurs after the second R(ACK) block, then the PCD shall report a time‐out error to the terminal and continue as specified in 10.3.5.9 within tTIMEOUT and tTIMEOUT + tRESETDELAY. If no frame waiting time extension is requested by the PICC, then tTIMEOUT is equal to FWT + FWT. Otherwise, tTIMEOUT is equal to (FWT x WTXM) + FWT. 16. In Annex A.4 Sequences and Frames, add the PCD Value for TPCD as follows: Topic Table A.4: Sequences and Frames Parameter … TPCD PCD Value Min Max 16.4 PICC Value Min Max … Units ms

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