SB nº AN-13 : TVR and TSI Bit Settings Following Script Processing (Clarification)

2003-12-01T00:00:00+00:00 v1.0 Specification Bulletins

Application Note N°13 First Edition December 2003 TVR and TSI Bit Settings Following Script Processing

Applicability

This Application Note applies to:

EMV '96 Integrated Circuit Card Specification for Payment Systems Version 3.1.1 and EMV 2000 Integrated Circuit Card Specifications for Payment Systems Version 4.0.

Related Documents

None Issuer to card script processing is described in EMV 2000 in Book 3, section 6.10, and in Book 4, sections 2.3.9 and 8.2.4. Depending upon whether a script is received, and, if so, whether it is successfully executed, certain bits are set in the Terminal Verification Results (TVR) and Transaction Status Information (TSI), and the Issuer Script Results must be set accordingly. The descriptions in the EMV Specifications use the terms ‘processed’ and ‘performed’ and it is not always clear how these terms should be understood in order to determine how to correctly set the TVR and TSI bits, and the Issuer Script Results. This Application Note sets out to clarify this. Four possible scenarios can occur when processing a script. These scenarios are described below, together with the expected results in terms of the setting of the appropriate TVR bits, the TSI bit and the Issuer Script Results. In the following descriptions, the:

TVR bits refer to TVR Byte 5 b6 & b5 (depending on whether it is a tag '71' and/or tag '72' script) as defined in Book 3, Annex C, Table C6.
TSI bit refers to TSI Byte 1, b3 as defined in Book 3, Annex C, Table C7 The Issuer Script results are defined in Book 4, Annex A, section A5. Scenario 1 - A script is received, it parses correctly, the commands are sent to the card, and the card returns '9000', '62xx' or ‘63xx’ to all commands received. In This document contains proprietary and confidential information of EMVCo LLC. Copyright © EMVCo LLC 2003 this scenario the TSI bit is set and the TVR bits are not set. The first byte of the Issuer Script Results shall be set to '2x', script processing successful. Scenario 2 - A script is received, it parses correctly, the commands are sent to the card, but the card does not return '9000', '62xx' or '63xx' to one of the commands received. In this scenario the TSI bit is set and the appropriate TVR bit(s) are also set. The first byte of the Issuer Script Results shall be set to '1x', script processing failed. Note that if '9000', '62xx' or '63xx' is not returned to a command sent to the card, no further commands from that script shall be sent to the card, even if they exist. Scenario 3 - A script is received, it does not parse correctly, and so no commands are sent to the card. In this scenario the TSI bit is set and the appropriate TVR bit(s) are also set. The first byte of the Issuer Script Results shall be set to '00', script not performed. Scenario 4 - No script is received. In this scenario neither the TSI bit nor the TVR bit(s) are set. In this event there will be no Issuer Script Results. Additional information It is possible, but not recommended, that commands may be sent to the card ‘on the fly’ as a script is parsed. In this event, if a parsing error occurs before any commands are sent to the card, the first byte of the Issuer Script Results is set to ‘00’ or, if any command has been sent to the card, it is set to ‘1x’. The appropriate TVR bits and the TSI bit are set. If more than one script is received:
The TSI bit is set
The TVR bit(s) are set (as described in Scenarios 2 and 3) if any error occurs
The Issuer Script Results are set as described in Scenarios 1 through 3 for each script on a script-by-script basis