ACS ACR128, User Manual

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ACR128 Dual Interface Smart Card Reader
5.1.2 ATR format for ISO 14443 Part 4 PICCs .
Table 8: ISO 14443 Part 4 ATR Format
Byte Value
(Hex)
Designation Description
0 3B Initial Header
1 8N T0 Higher nibble 8 means there are no TA1, TB1 and
TC1. Only TD1 follows.
Lower nibble N is the number of historical bytes
(HistByte 0 to HistByte N-1)
2 80 TD1 Higher nibble 8 means there are no TA2, TB2 and
TC2. Only TD2 follows.
Lower nibble 0 means T = 0
3 01 TD2 Higher nibble 0 means no TA3, TB3, TC3 and TD3
follow.
Lower nibble 1 means T = 1
XX T1 4
to
3 + N
XX
XX
XX Tk
Historical Bytes:
ISO14443A:
The historical bytes from ATS response. Refer to
the ISO14443-4 specification.
ISO14443B:
The higher layer response from the ATTRIB
response (ATQB). Refer to the ISO14443-3
specification.
4+N UU TCK Exclusive-ORing of all the bytes T0 to Tk
Example 1. Consider the ATR from DESFire as follows:
DESFire (ATR) = 3B 86 80 01 06 75 77 81 02 80 00
ATR
ATS
Initial Header T0 TD1 TD2
T1 Tk TCK
3B 86 80 01 06 75 77 81 02 80 00
This ATR has 6 bytes of ATS which is: [06 75 77 81 02 80]
NOTE: Use the APDU “FF CA 01 00 00” to distinguish the ISO14443A-4 and ISO14443B-4 PICCs
and retrieve the full ATS if available. The ATS is returned for ISO14443A-3 or ISO14443B-3/4 PICCs
.
Example 2. Consider the ATR from ST19XRC8E, which is as follows:
ST19XRC8E (ATR) = 3B 8C 80 01 50 12 23 45 56 12 53 54 4E 33 81 C3 55
ATR
ATS
Initial Header T0 TD1 TD2
T1 Tk TCK
3B 86 80 01 50 12 23 45 56 12 53 54 4E 33 81 C3 55
Since this card is compliant to ISO 14443 Type B, the response would be ATQB and it is 12
bytes long with no CRC-B.
Note: You can refer to the ISO7816, ISO14443 and PCSC standards for more details.
Page 13 of 36
ACR128 API
Version 1.7 May 2008