#7816-4 Template

#Description

ISO/IEC 7816-4 is the standard for smart card commands. Most contactless smartcards use the ISO/IEC 7816-4 on top of a ISO/IEC 14443-4 ‘T=CL’ or “ISO-DEP” communication channel.

According to this standard, the card is structured as a (lightweight) file-system, providing Directory Files and Elementary Files.

The standard-defined Instruction-set allows to navigate in the smartcard’s directories and file tree, and to read the data from its files.

Every Instruction call is named an “APDU”.

The card’s Response to every Instruction is always terminated by a 2-B Status Word which denotes the success (values 9xxx, typically 9000) or the failure (values 6xxx).

Using this ISO/IEC 7816-4 Template, the Reader is able to send 1, 2 or 3 APDUs and to extract the data from the card’s last Response.

#Remark

This Template is suitable to read data on virtually any contactless smartcard, provided that said data is accessible in the plain and without prior authentication.

Reading data from a secure smartcard (such as Desfire) or an NFC applications (such as Apple VAS and Google SmartTap) is possible only using a dedicated Template that implements both the application-specific security and Instruction-set at once.

#Lookup List

This Template supports 4 protocol selectors:

LKL Value	Selected protocol(s)
13	ISO-DEP on NFC-A and NFC-B - ISO/IEC 14443-4 ‘T=CL’ types A and B
11	ISO-DEP on NFC-A - ISO/IEC 14443-4 ‘T=CL’ type A
12	ISO-DEP on NFC-B - ISO/IEC 14443-4 ‘T=CL’ type B
72	Innovatron Radio Protocol (legacy Calypso cards)

#Registers

This Template uses 8 configuration registers:

Alias	Offset	Name	Description
LKL	0	Lookup List	See the Lookup List table above
APDU1	5	1st APDU	This is typically a SELECT APPLICATION or a SELECT DIRECTORY Instruction.
APDU2	6	2nd APDU	This is typically a SELECT FILE Instruction.
APDU3	7	3rd APDU	This is typically a READ BINARY or READ RECORD Instruction.
TOF	1	Output Size and Format	See details below
LOC	3	Location of Data	See details below
OPT	4	Options	Template-specific Options
PFX	2	Prefix	Template-specific Prefix

#APDU1 - 1st APDU

Offset : 5

Size : 32

Remark : The Reader checks the Status Word. In case of any error (SW!=9xxx), the Template is terminated.

#APDU2 - 2nd APDU

Offset : 6

Size : 32

Remark : The Reader checks the Status Word. In case of any error (SW!=9xxx), the Template is terminated.

#APDU3 - 3rd APDU

Offset : 7

Size : 32

Remark : The Reader checks the Status Word. In case of any error (SW!=9xxx), the Template is terminated.

#TOF - Output Size and Format

Offset : 1

Size : 2

#Byte 0 : RAW Mode

Condition : When RAW Mode is selected (Bit 6 in Byte 0 is 0)

Bit	Role	Values
7	Invert Data?	0 : Transmit the sequence of bytes as is 1 : Transmit the sequence of bytes in reverse order
6	Mode	0 : RAW Mode (Data is a numerical value) 1 : String Mode (Data is an ASCII string)
5	Padding if Data is shorted than specified length	0 : Padd with 0 on the left 1 : Padd with F on the right
4	Remove leading zeroes?	0 : Keep all digits 1 : Suppress 0 digits on the left of the Data
3-0	Length and Format	0 : Decimal, 10 digits (truncation on 4-B) 1 : Raw (hex), 4 bytes (32 bits) 2 : Raw (hex), 8 bytes (64 bits) 3 : Raw (hex), 5 bytes (40 bits) 4 : Raw (hex), 10 bytes (80 bits) 5 : Raw (hex), 7 bytes (56 bits) 6 : Raw (hex), 11 bytes (88 bits) 7 : RFU 8 : Raw (hex), 16 bytes (128 bits) 9 : Raw (hex), 20 bytes (160 bits) 10 : Raw (hex), 24 bytes (196 bits) 11 : Raw (hex), 32 bytes (256 bits) 12 : Decimal, 12 digits (truncation on 5-B) 13 : Decimal, 13 digits (truncation on 5-B) 14 : Decimal, variable length 15 : Raw (hex), variable length

#Byte 0 : String Mode

Condition : When String Mode is selected (Bit 6 in Byte 0 is 1)

Bit	Role	Values
7	Invert Data?	0 : Transmit the sequence of characters as is 1 : Transmit the sequence of characters in reverse order
6	Mode	0 : RAW Mode (Data is a numerical value) 1 : String Mode (Data is an ASCII string)
5	Padding if Data is shorted than specified length	0 : Variable length (no padding) 1 : Padd with (space characters) on the right until the specified length
4	Short string or Long string?	0 : Short string (truncate to 16 characters or less) 1 : Long string (more than 16 characters)
3-0	Length	0 : 16 characters 1 : 1 character 2 : 2 characters 3 : 3 characters 4 : 4 characters 5 : 5 characters 6 : 6 characters 7 : 7 characters 8 : 8 characters 9 : 9 characters 10 : 10 characters 11 : 11 characters 12 : 12 characters 13 : 13 characters 14 : 14 characters 15 : 15 characters

#Byte 1 : Options for Long String

Condition : When Long String Mode is selected (Bit 6 in Byte 0 is 1 and Bit 4 is 1)

Use this byte to specify the exact length to read from the card. Valid range is 1 to 255.

#LOC - Location of Data

Offset : 3

Size : 2

#Byte 0 : Shift Bytes

Leading bytes to suppress.

#Byte 1 : Shift Bits

Leading bits to suppress; valid range is 0 to 7.

#OPT - Options

Offset : 4

Size : 1

If this register is set, the Reader adds a token to its output to tell the receiver what kind of credential has been read.

Bit	Role	Values
7-4	RFU
3-2	Position of the Card Type Token	0 : Before the Prefix 1 : After the Prefix, before the Data 2 : After the Data (before the Suffix) 3 : RFU
1-0	Add a Card Type Token to the output stream?	0 : Do not add a Card Type Token 1 : Add 1F hex value as Card Type Token 2 : Add T char as Card Type Token 3 : RFU

#PFX - Prefix

Offset : 2

Size : 8

A Template-specific Prefix, that is added after the Reader’s global Prefix.

Remark : Use \t for a Tab, \n for Enter, \b for Back space, \v for Vertical space.