The ST25TA16K device is a dynamic NFC/RFID tag that can be accessed from the RF interface. The RF interface is based on the ISO/IEC 14443 Type A standard.

The ST25TA16K is compatible with the NFC Forum Type 4 Tag specifications and supports all corresponding commands.

Figure 1 shows the block diagram of the ST25TA16K device.

Figure 1. ST25TA16K block diagram

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Signal name

AC0, AC1

Table 1. Signal names

Function

Antenna coils

Direction

069

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ST25TA16K Functional description

The ST25TA16K has just one functional mode (see Table 2 ).

Mode

Tag mode

Table 2. Functional mode

Supply source

RF field only

Comments

The interface is connected

The ST25TA16K is supplied by the RF field and can communicate with an RF host (RFID reader or an NFC phone). The User memory can only be accessed by the RF commands.

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Signal descriptions ST25TA16K

2.1 Antenna coil (AC0, AC1)

These inputs are used to connect the device to an external coil exclusively. It is advised not to connect any other DC or AC path to AC0 or AC1.

When correctly tuned, the coil is used to access the device using NFC Forum Type 4 commands.

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ST25TA16K

3

ST25TA16K memory management

ST25TA16K memory management

The ST25TA16K supports the NDEF Tag Application as defined in the NFC Forum Type 4

Tag. The ST25TA16K is composed of three files:

• one Capability Container file;

• one NDEF file;

• one System file: this is an ST-proprietary file.

The System file contains some information on the configuration of the ST25TA16K device.

The CC file gives some information about the ST25TA16K itself and the NDEF file. The

NDEF file contains the User data.

The file identifier is the value used in the Select command to select a file.

File identifier

0xE101

0xE103

0x0001

System file

CC file

NDEF file

Table 3. File identifier

Meaning

The CC file gives some information about the ST25TA16K and the NDEF file. This file is a read-only file for the RF host and cannot be modified by issuing a write command.

The T, Read Access and Write Access fields can be changed by the RF host through a

specific process (refer to Section 7: Functional procedures ).

File offset

0x0000

0x0002

0x0003

0x0005

Table 4. CC file layout for one NDEF file

Meaning

Number of bytes of CC file

Mapping version

(1)

Maximum number of bytes that can be read

Maximum number of bytes that can be written

Value Comments

0x000F 15 bytes

0x20 or 0x10 V 2.0 or V 1.0

0x00F6 246 bytes

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ST25TA16K memory management ST25TA16K

File offset

0x0007

0x0008

0x0009

0x000B

Table 4. CC file layout for one NDEF file (continued)

Meaning Value

0x04

(2)

0x06

0x0001

NDEF file control TLV

0x0800

0x000D

0x000E

1. According to the reader.

2. Delivery state.

0x00

(2)

0x00

(2)

Comments

T field

L field

FileID

Maximum NDEF file size

Read access

Write access

The NDEF file contains the NDEF message that contains the User data. The RF host can read and write data inside the file. The first two bytes named NDEF Message Length define the size of the NDEF message. The NDEF Message Length shall be managed by the application and the ST25TA16K device does not check if its value is relevant vs the data written by the RF host. The ST25TA16K device uses the NDEF Message Length, e. g. the standard read can be processed only inside the NDEF message; otherwise, the

ST25TA16K device returns an error code. For more details about the read command, refer to

Section 5.6.7: ReadBinary command .

File offset

0x0000

0x0004

...

0x07FC

Table 5. NDEF file layout

Byte 0 Byte 1

NDEF message length

User data

...

User data

...

Byte 2

User data

...

Byte 3

User data

...

User data

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The system file specifies the configuration of the ST25TA16K. Table 6 lists the different

fields.

File offset

0x0000

0x0002

0x0003

Field name

Length system file

ST reserved

Table 6. Field list

Number of bytes

Read access

Write access

none none

Delivery state

0x0012

0x01

0x00

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ST25TA16K ST25TA16K memory management

File offset Field name

Table 6. Field list (continued)

Number of bytes

Read access

Write access

0x0004

0x0005

0x0006

0x0007

0x0008

0x000F

0x0011

ST reserved

NDEF File number

(RFU)

UID

Memory Size

Product Code

1. x values are defined by ST to insure UID unicity.

RF none none none none none none none

Delivery state

0x11

0x00

0x01

0x00

0x02C5 xx xx xx xx xx

(1)

0x07FF

0xC5

3.2

3.2.1

Read and write access rights to the memory

An NDEF file can be locked for read or write accesses. It is also protected by a 128-bit password that the host shall present before accessing the NDEF file. There are two 128-bit passwords, one for the read access and the other one for the write access.

An NDEF file can be permanently locked for read or write accesses. Thus, the host cannot access the NDEF file.

The read password shall be sent to the ST25TA16K device before reading a read-locked

NDEF file.

The write password shall be present on the ST25TA16K device before writing a write-locked

NDEF file. The write password shall be sent to change the read or write access. The read or write access right is defined for the NDEF file.

State of the Read and Write access rights

Two bytes in the CC file are used to define the Read and Write access rights to the NDEF file. For more details, refer to

Section 3.1.2: CC file layout .

Value

Table 7. Read access right

Meaning

0x00

0x80

0xFE

Read access without any security

Locked (1)

Read not authorized

1. The read password shall be sent before reading in the NDEF file.

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ST25TA16K memory management ST25TA16K

Value

Table 8. Write access right

Meaning

0x00

0x80

0xFF

Write access without any security

Locked

(1)

Write not authorized

1. The write password shall be sent before writing in the NDEF file.

The state 0xFF and 0xFE cannot be changed by using the Read or Write passwords.

The state diagram on Figure 2

shows how to change the access right to read an NDEF file.

Figure 2. Changing the read access right to an NDEF file

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/RFNWKH1'()ILOH

8QORFNWKH1'()ILOH

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3HUPDQHQWO\ORFNWKH1'()ILOH

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1. See the procedure to lock the read access ( Section 7.4: Locking an NDEF file ).

2. See the procedure to unlock the read access (

Section 7.5: Unlocking an NDEF file

3. See the procedure to permanently lock the read access (

Section 7.6: Reaching the read-only state for an

NDEF file ).

4. Proprietary state, not defined by NFC Forum Type 4 Tag.

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ST25TA16K ST25TA16K memory management

The state diagram on

Figure 3 shows how to change the write access right to an NDEF file.

Figure 3. Changing the write access right to an NDEF file

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/RFNWKH1'()ILOH

8QORFNWKH1'()ILOH

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[))

069

1. See the procedure to lock the write access.

2. See the procedure to unlock the write access.

3. See the procedure to permanently lock the write access (

Section 7.6: Reaching the read-only state for an

NDEF file ).

4. Proprietary state, not defined by NFC Forum Type 4 Tag.

Access right life time

The access right life time is validated while the NDEF file is selected or until the end of the

RF session. Once the read or write access right is granted, the host can send one or more

ReadBinary or UpdateBinary commands.

At the end of a session or when the host selects another file, the read and write access rights are initialized.

Note:

The NDEF file passwords protect the read or write access from an RF interface from/to an

NDEF file.

Two NDEF file passwords are available for each NDEF file:

• Read password

• Write password

The length of a password is 128 bits (16 bytes).

The delivery state for all passwords is 0x00000000000000000000000000000000.

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Communication mechanism ST25TA16K

4.1

This chapter describes the principle of communication between an RF host and the

ST25TA16K device.

Master and slave

The ST25TA16K acts as a slave device on the RF channel and therefore waits for a command from the RF host before sending its response.

The RF host shall generate the RF field and the RF commands.

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ST25TA16K

5 RF command sets

RF command sets

This section describes the ST25TA16K command sets that can be issued by the RF host.

There are three command families:

• the NFC Forum Type 4 Tag command set

• the ISO/IEC 7816-4 command set

• the proprietary command set

The NFC Forum Type 4 Tag command set and the ISO/IEC 7816-4 command set use the I-

Block format. For more details about the I-Block format, refer to Section 5.2: I-Block format .

Two other command formats exist:

• the commands using the R-Block format

• the commands using the S-Block format

For more details about these formats, refer to the corresponding sections:

Section 5.3: R-

Block format

and

Section 5.4: S-Block format

This section gives a brief description of the RF host commands. The format of these command sets is the I-Block format.

Table 9 lists the RF command sets.

Family command set

Table 9. RF command sets

Command name

Class byte

Instruction code

Brief description

NFC Forum

Type 4 Tag

NDEF Tag Application Select

CC select

NDEF select

System select

ReadBinary

UpdateBinary

Verify

ISO/IEC 7816-4

ChangeReferenceData

EnableVerificationRequirement

0x00

DisableVerificationRequirement 0x00

0xA4

0xB0

0xD6

0x20

0x24

0x28

0x26

NDEF Tag Application

Select

Selects the CC file

Selects the NDEF file

Selects the system file

Reads data from file

Writes or erases data to a

NDEF file

Checks the right access of a NDEF file or sends a password

Changes a Read or write password

Activates the password security

Disables the password security

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RF command sets ST25TA16K

Family command set

Table 9. RF command sets (continued)

Command name

Class byte

Instruction code

EnablePermanentState

ST proprietary ExtendedReadBinary

UpdateFileType

0xA2

0x28

0xB0

0xD6

Brief description

Enables the Read Only or

Write Only security state

Reads data from file

Sets file type to NDEF or proprietary

5.1 Structure of the command sets

The exchange of data between the RF host and the ST25TA16K uses three kinds of data formats, called blocks:

• I-Block: to exchange the command and the response

• R-Block: to exchange positive or negative acknowledgment

• S-Block: to use either the Deselect command or the Frame Waiting eXtension (WTX) command or response

This section describes the structure of the I-Block, R-block and S-Block. This format is used for the application command set.

The I-Block is used to exchange data between the RF host and the ST25TA16K. It is composed of three fields.

Table 10 details the I-Block format.

Name

PCB

Length 1 byte

PCB field

DID field (optional)

RF host to ST25TA16K: C-APDU

ST25TA16K to RF host: R-APDU

2 CRC bytes

Table 10. I-Block format

SoD Payload

DID -

1 byte 1 to 251 bytes

EoD

CRC

2 bytes

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ST25TA16K

5.2.1

RF command sets b7-b6

0b00

I-Block

RFU

Must be set to 0

DID field, if bit is set

Must be set to 0

Must be set to 1

Block number

Table 11. PCB field of the I-Block format b5 b4 b3 b2

0 0 X 0 b1

1 b0

When the RF host sends a command to the ST25TA16K the format of the payload is the

C-APDU.

When the ST25TA16K sends a command to the RF host, the format of the payload is the

R-APDU.

C-APDU: payload format of a command

The C-APDU format is used by the RF host to send a command to the ST25TA16K.

Table 12 describes its format.

Name

INS

Table 12. C-APDU format

Payload field

P1 P2 CLA

Length 1 byte 1 byte 1 byte

Class byte

0x00: standard command

0xA2: ST command

Instruction byte

Param Byte 1

Param Byte 2

Number of bytes of the Data field

Data bytes

Number of bytes to be read in the ST25TA16K memory

1 byte

Data Le

Lc byte 1 byte

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RF command sets ST25TA16K

The ST25TA16K uses the I-Block format to reply to a command that used the I-Block format. This format is described in

Table 13 .

Name

Table 13. R-APDU format

Payload field

Data (optional) SW1

Le byte 1 byte Length

Data

Status byte 1

Status byte 2

SW2

1 byte

The R-Block is used to convey positive or negative acknowledgment between the RF host and the ST25TA16K.

Table 14. R-Block format

PCB

R(ACK) without the DID field: 0xA2 or 0xA3

R(ACK) with the DID field: 0xAA or 0xAB

R(NAK) without the DID field: 0xB2 0xB3

R(NAK) with the DID field: 0xBA 0xBB

CRC

2 CRC bytes

There are two kinds of R-Blocks:

• R(ACK): the acknowledgment block sent by the RF host or by the ST25TA16K

• R(NAK): the non-acknowledgment block sent by the RF host or by the ST25TA16K b7-b6

0b10

R-Block

RFU

0: NAK

1: ACK

0: DID field is not present

1: DID field is present

Must be set to 0

RFU

Block number

Table 15. R-Block detailed format b5 b4 b3

1 X X b2

0 b1

0 b0

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ST25TA16K RF command sets

The S-Block is used to exchange control information between a reader and a contactless tag.

NFC frame

PCB

Table 16. S-Block format

SoD

DID

Payload

EoD

CRC

Length 1 byte 1 byte 0 to 1 byte

0xC2: for S(DES) when the DID field is not present

0xCA: for S(DES) when the DID field is present

0xF2: for S(WTX) when the DID field is not present

0xFA: for S(WTX) when the DID field is present

DID field (optional)

WTX field

(1)

2 CRC bytes

1. This field is present when b5-b4 bits are set to 0b11 (S-Block is a WTX). see

Table 17: S-Block detailed format .

2 bytes

There are two requests using the S-Block format:

• S(DES): the deselect command

• S(WTX): the Waiting Frame eXtension command or response.

Table 17. S-Block detailed format b5-b4 b3 b2

X X 0 b7-b6

0b11

S-Block

0b00: Deselect

0b11: WTX

0: DID field is not present

1: DID field is present

RFU

RFU b1

1 b0

Note: After receiving the deselect command, the session is released and ST25TA16K enters the

Standby power mode.

In response to a RATS command, ST25TA16K returns FWI parameter (default frame waiting time used); when ST25TA16K needs more time for a command execution, it requests a frame waiting time extension by responding 0xF2 0xWTX (Request waiting time = FWI *

WTX). If the reader accepts ST25TA16K request, it acknowledges by sending the command

0xF2 0xWTX. The frame waiting time becomes FWI * WTX for the current command only.

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RF command sets

5.5 CRC of the RF frame

ST25TA16K

The two CRC bytes check the data transmission between the RF host and the ST25TA16K.

For the RF frame, the CRC is computed on all the data bits in the frame, excluding parity bits, SOF and EOF, and the CRC itself.

The CRC is as defined in ISO/IEC 13239. The initial register content shall be 0x6363 and the register content shall not be inverted after calculation.

5.6 NFC Forum Type 4 Tag protocol

5.6.2

Command name

NDEF Tag Application Select

Capability Container Select

NDEF Select

System File Select

ReadBinary

UpdateBinary

Table 18. Command set overview

Brief description

Select the NDEF Tag Application

Select the capability container (CC) file using the Select command

Select the NDEF file

Select the system file

Read data from a file

Write new data to a file

Status and error codes

This section lists the status and the error code of the ST25TA16K.

Value

Table 19. Status code of the ST25TA16K

SW1

0x90

SW2

0x00

Comment

Command completed successfully

Length

Value

Table 20. Error codes of the ST25TA16K

SW1 SW2

1 byte

0x62

0x63

0x65

1 byte

0x80

0x82

0x00

0xCX

0x81

Comment

File overflow (Le error)

End of file or record reached before reading Le bytes

Password is required

Password is incorrect, X further retries allowed (X can take value 0,1, 2)

Unsuccessful updating

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ST25TA16K RF command sets

Length

Value

Table 20. Error codes of the ST25TA16K (continued)

SW1 SW2

Comment

1 byte 1 byte

0x67 0x00

0x69

0x6A

0x6D

0x6E

0x81

0x82

0x84

0x80

0x82

0x84

0x86

0x00

Wrong length

Command is incompatible with the file structure

Security status not satisfied

Reference data not usable

Incorrect parameters Le or Lc

File or application not found

File overflow (Lc error)

Incorrect P1 or P2 values

INS field not supported

Class not supported

5.6.3 NDEF Application Select command the RF host shall send this command to activate the NDEF Tag Application.

To activate the NDEF Tag Application, the RF host sends the Select command (see

Table 21 ) in addition to the sequence defined in the NFC Forum digital protocol.

Table 21 defines the C-APDU of the Select command to select the NDEF Tag Application

(called NDEF Tag Application Select).

Name

Table 21. C-APDU of the NDEF Tag Application Select command

CLA INS P1 P2 Lc Data

0x00 0xA4 0x04 0x00 0x07

0xD27600

00850101

Class byte

Select instruction code

P1 field

P2 field

Number of bytes of data

Application ID

Le field

0x00

Table 22 defines the R-APDU of the NDEF Tag Application Select command.

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RF command sets ST25TA16K

Length

Value

Table 22. R-APDU of the NDEF Tag Application Select command

Data SW1 SW2 Comment

1 byte

0x90

0x6A

0x6D

1 byte

0x00

0x82

0x00

Command completed

NDEF Tag Application not found

Class not supported

The RF host uses the Capability Container Select procedure to select the capability container (CC) file.

The CC file is selected when this command returns "command completed" in the R-APDU.

Table 23 defines the C-APDU of the Select command to select the CC file (called Capability

Container Select).

Name

Table 23. C-APDU of the Capability Container Select command

CLA

Class byte

0x00

Select instruction code

P1 field

P2 field

Number of bytes of data

CC file ID

INS

0xA4

0x00

0x0C

0x02

Data

0xE103

Table 24 defines the R-APDU of the CC Select command.

Length

Value

Table 24. R-APDU of the Capability Container Select command

Data SW1 SW2 Comment

1 byte

0x90

0x6A

0x6D

1 byte

0x00

0x82

0x00

Command completed

File or application not found

Class not supported

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The RF host uses the NDEF Select command to select the NDEF file.

The NDEF file is selected when this command returns "command completed" in the R-

APDU.

Table 25 defines the C-APDU of the Select command to select the NDEF file (called

NDEF Select).

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ST25TA16K

5.6.6

RF command sets

Name CLA

Table 25. C-APDU of the NDEF Select command

Class byte

0x00

Select instruction code

P1 field

P2 field

Number of bytes of data

0x0001: first NDEF file

INS

0xA4

0x00

0x0C

0x02

Data

0x000X

Table 26 defines the R-APDU of the NDEF Select command.

Length

Value

Data

Table 26. R-APDU of the NDEF Select command

SW1 SW2 Comment

1 byte

0x90

0x6A

1 byte

0x00

0x82

Command completed

File or application not found

System File Select command

The RF host uses this command to select the system file.

The System file is selected when this command returns "command completed" in the R-

APDU.

Table 27 defines the C-APDU of the command to select the System file (called System

Select).

Name

Table 27. C-APDU of the System File Select command

CLA

Class byte

0x00

Select instruction code

P1 field

P2 field

Number of bytes of data

System file ID

INS

0xA4

0x00

0x0C

0x02

Data

0xE101

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RF command sets ST25TA16K

Table 28 defines the R-APDU of the System File Select command.

Length

Value

Table 28. R-APDU of the System File Select command

Data SW1 SW2 Comment

1 byte

0x90

0x6A

1 byte

0x00

0x82

Command completed

Capability container not found, no data is returned

On receiving the ReadBinary command, the ST25TA16K reads the requested memory field and sends back its value in the R-APDU response.

Before sending a ReadBinary command, a file shall be selected by using a Select command.

The Response of the ReadBinary command is successful when the data to be read is within the selected file

(a)

; in other words, when the sum of P1-P2 and Le fields is equal to or lower than the selected file length.

Table 29 defines the ReadBinary command.

Name

Table 29. C-APDU of the ReadBinary command

CLA INS P1 & P2

Class byte

0x00

Read instruction code

Offset in the file selected

0xB0

Number of bytes to read between

0x01 ≤ Le ≤ max(Selected File length, 0xF6)

2 bytes

Data

1 byte

Table 30 defines the R-APDU of the ReadBinary command.

Length

Value

Table 30. R-APDU of the ReadBinary command

Data SW1 SW2 Comment

Content read

1 byte

0x90

1 byte

0x00

Command completed

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a. For more details about CC file, refer to

Section 3.1.2: CC file layout .

For more details about NDEF file, refer to

Section 3.1.3: NDEF file layout

For more details about System file, refer to Section 3.1.4: System file layout .

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Value

RF command sets

Table 30. R-APDU of the ReadBinary command (continued)

Data SW1 SW2 Comment

0x67

0x69

0x6A

0x6E

0x00

0x82

0x00

Wrong length

Security status not satisfied

File or application not found

Class not supported

Note:

On receiving the UpdateBinary command, the ST25TA16K writes the data field into the selected file and sends back a status in the R-APDU response.

Before sending an UpdateBinary command, a file shall be selected by issuing a Select command.

Table 31 defines the UpdateBinary command.

Name

Table 31. C-APDU of the UpdateBinary command

CLA INS P1 & P2 Lc Data

2 bytes 1 byte Lc bytes -

Class byte

0x00

Write instruction code

0xD6

Offset in the file selected

Number of bytes of data (0x01 ≤ ≤

Data to write in the ST25TA16K memory

Length

Value

Table 32 defines the R-APDU of the UpdateBinary command.

Table 32. R-APDU of the UpdateBinary command

Data SW1 SW2 Comment

1 byte

0x90

0x65

0x67

0x69

0x6A

0x6E

1 byte

0x00

0x81

0x00

0x82

0x00

Command completed

Unsuccessful updating

Wrong length

Security status not satisfied

File or application not found

Class not supported

For further return codes and definitions, refer to Status and error codes

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RF command sets

5.7 ISO/IEC 7816-4 commands

ST25TA16K

The ISO/IEC 7816-4 command set offers some extended features such as the protection of the NDEF file. This command set is used to manage the right access of the NDEF file.

The Verify command has two functions:

Check if a password is required to access to the NDEF file (the LC field = 0x00).

2. Check that the password embedded in the Verify command allows the access to the memory (the Lc field = 0x10 and the password is present).

When the Lc field if equal to 0x00, the verify command returns a success code (0x90 00) provided that the access to the NDEF file does not require a password. When the access to the NDEF file is protected, the response to the Verify command returns an error code

(0x63 00).

When the Lc field equals 0x10, on receiving the Verify command, the ST25TA16K compares the requested password with the data contained in the request and reports whether the operation has been successful in the response.

Before sending this command, an NDEF file shall be selected by issuing the NDEF Select command. Thus, this command checks the right access condition of the last NDEF file selected.

After a successful command, an access is granted for the whole NDEF file.

Table 33 defines the Verify command.

Name CLA

Table 33. Verify command format

INS P1 & P2

0x00 0x20

Class byte

Instruction code

Password identification

0x0001: Read NDEF password transmit

0x0002: Write NDEF password transmit

Other: RFU

0x00: the password is not present

0x10: the password is present in the data field

Password

2 bytes

1 byte

Data

Lc bytes

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ST25TA16K

5.7.2

RF command sets

Table 34 defines the R-APDU of the Verify command.

Data

Table 34. R-APDU of the Verify command

SW1 SW2 Comment

Length

Value

1 byte

0x90

0x69

0x6A

0x63

0x6E

1 byte -

0x00 Command completed, the password is correct

0x85

The conditions of use are not satisfied (e.g. no

NDEF file was selected)

0x81

0x82

0x80

0x00

Command incompatible with file structure

Security status not satisfied

Incorrect parameter in command data field

A password is required

0xCX

0x00

(1)

The password transmitted is incorrect and X encodes the number of further allowed retries.

Class not supported

1. At each session, the RF host can check a password 3 times.

Change Reference Data command

The Change Reference Data command replaces the read or write password related to the

NDEF files previously selected. It can be performed only if the security status satisfies the security attributes for this command.

Before sending this command, the verify command with the correct NDEF write password shall be issued. Thus, this command changes the reference data of the NDEF file.

Table 35 defines the Change Reference Data command.

Name

Table 35. Change reference data command format

CLA INS P1 & P2

Class byte

0x00 0x24

Instruction code

Password identification

0x0001: Read password transmit

0x0002: Write password transmit

Other: RFU

0x10: the password is present in the data field

NDEF file Password

2 bytes

1 byte

Data

Lc bytes

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RF command sets ST25TA16K

Length

Value

Table 36 defines the R-APDU of the Change Reference Data command.

Table 36. R-APDU of the Change Reference Data command

Data SW1 SW2 Comment

1 byte

0x90

0x69

0x65

0x69

0x6A

0x6E

1 byte -

0x00 Command completed, the access right has been changed

0x81 Command is incompatible with the file structure

0x81 Unsuccessful updating

0x82 Security status not satisfied

0x80 CC file or System file selected

0x82 File or application not found

0x86 Incorrect P1 or P2 values

0x00 Class not supported

5.7.3 Enable Verification Requirement command

The Enable Verification Requirement command activates the protection by password of the

NDEF file. When this command is successful, the read or write access to the NDEF file is protected by a 128-bit password. It can be performed only if the security status satisfies the security attributes for this command.

This command can update the right access of the NDEF file by writing into the EEPROM. In this case, the response timing will be around 5 ms.

Before sending this command, the verify command with the correct NDEF write password shall be issued. Thus, this command changes the access right of the NDEF file.

Table 37 defines the Enable Verification requirement command.

Name

Table 37. Enable Verification Requirement command format

CLA INS P1 & P2

0x00 0x28 2 bytes

Class byte

Instruction code

New security attributes

0x0001: Enable the read protection of the NDEF file

0x0002: Enable the write protection of the NDEF file

Other: RFU

Data

The last five bits identify the password sent in the Verify command.

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ST25TA16K RF command sets

Table 38 defines the R-APDU of the Enable Verification Requirement command.

Length

Value

Table 38. R-APDU of the Enable Verification Requirement command

Data SW1 SW2 Comment

1 byte

0x90

0x69

0x6A

1 byte

0x00

0x81

0x82

0x80

0x82

0x86

Command completed, the password is correct

Command is incompatible with the file structure

Security status not satisfied

CC file or System file selected

File or application not found

Incorrect P1 or P2 values

5.7.4 Disable Verification Requirement command

The Disable Requirement command deactivates the protection by password of the NDEF file. When this command is successful, the read or write access to the NDEF file is granted without security requirements. It can be performed only if the security status satisfies the security attributes for this command.

Before sending this command, the Verify command with the correct NDEF write password shall be issued. Thus, this command changes the access right of the NDEF file.

This command can update the right access of the NDEF file by writing into the EEPROM. In this case, the response timing will be around 6 ms.

Table 39 defines the Disable Verification Requirement command.

Name

Table 39. Disable Verification Requirement command format

CLA INS P1 & P2

Class byte

Instruction code

0x00 0x26 2 bytes

New security attributes

0x0001: Disable the read protection of the NDEF file

0x0002: Disable the write protection of the NDEF file

Other: RFU

Data

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RF command sets ST25TA16K

Table 40 defines the R-APDU of the Disable Verification Requirement command.

Length

Value

Table 40. R-APDU of the Disable Verification Requirement command

Data SW1 SW2 Comment

1 byte

0x90

0x69

0x6A

0x6E

0x65

1 byte

0x00

0x81

0x82

0x80

0x82

0x86

0x00

0x81

Command completed, the password is correct

Command is incompatible with the file structure

Security status not satisfied

CC file or System file selected

File or application not found

Incorrect P1 or P2 values

Class not supported

Update failed

5.8 ST proprietary command set

The RF host can be issued with the command set described in this section.

On receiving the ExtendedReadBinary command, the ST25TA16K reads the requested memory field and sends back its value in the R-APDU response.

Before sending an ExtendedReadBinary command, a file shall be selected by issuing an

NDEF select command.

The response of the ExtendedReadBinary command will be successful even if the data to be read is beyond the NDEF message. The command returns an error code if the data to be read goes beyond the end of the file.

Name

Table 41. C-APDU of the ExtendedReadBinary command

CLA INS P1 & P2

Length

ST Class byte

0xA2 0xB0 2 bytes

Read instruction code

Offset in the file selected

Number of bytes to read between 0x01 ≤ Le ≤ 0xF6

Data

1 byte

Table 42 defines the R-APDU of the read binary command.

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Length

Value

Table 42. R-APDU of the ExtendedReadBinary command

Data SW1 SW2 Comment

Le bytes

Content read

1 byte

0x90

0x67

0x69

0x6A

0x6E

1 byte

0x00

0x82

0x86

0x00

Command completed

Wrong length

Security status not satisfied

File or application not found

Incorrect P1 or P2 values

Class not supported

The command configures the NDEF file to the ReadOnly or to the WriteOnly State.

This command can update the right access to the NDEF file by writing into the EEPROM. In this case, the response timing will be around 6 ms.

Table 43 defines the EnablePermanentState requirement command.

Name

Table 43. EnablePermanentState command format

CLA INS P1 & P2

Length

Class byte

0xA2 0x28 2 bytes

Instruction code

New security attributes

0x0001: Enable the read protection of the NDEF file

0x0002: Enable the write protection of the NDEF file

Other: RFU

Data

Table 44 defines the R-APDU of the EnablePermanentState command.

Length

Value

Table 44. R-APDU table of the EnablePermanentState command

Data SW1 SW2 Comment

1 byte

0x90

0x65

0x67

0x69

1 byte

0x00

0x81

0x00

0x82

Command completed

Update failed

Wrong length

Security status not satisfied

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RF command sets ST25TA16K

Value

Table 44. R-APDU table of the EnablePermanentState command (continued)

Data SW1 SW2 Comment

0x6A

0x80

0x82

0x6A 0x86

0x6E 0x00

CC file or System file selected

File or application not found

Incorrect P1 or P2 values

This command allows the user to modify the file type of a selected file to Proprietary file

(0x05) or NDEF file (0x04).

The command is executed only when the application and the file are selected and the file length and access right have previously been set to 0X00h (message invalid, all access rights granted).

This command will update the file type located in the CC file by writing in the EEPROM. In this case the response timing will be approximately 6 ms.

Table 45 defines the UpdateFileType command.

Name CLA

Length

Class byte

0xA2

Instruction code

P1 field

P2 field

Number of data bytes

File type

Table 45. UpdateFileType command format

INS P1 P2 Lc

0xD6 0x00 0x00 0x01

Data

0x04 or 0x05

Table 46 defines the R-APDU of the UpdateFileType command.

Length

Value

Table 46. R-APDU table of the UpdateFileType command

Data SW1 SW2 Comment

1 byte

0x90

0x69

0x6A

1 byte

0x00

0x82

0x80

0x82

0x86

Command completed

Security status not satisfied

CC file or System file selected

File or application not found

Incorrect P1 or P2 values

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ST25TA16K RF command sets

Value

Table 46. R-APDU table of the UpdateFileType command (continued)

Data SW1 SW2 Comment

0x6A 0x86

0x6E 0x00

Incorrect P1 or P2 values

5.9

5.9.1

Specific RF command set

This section describes the command set that can be issued only by the RF host.

Anticollision command set

Table 47 lists the commands that can be issued only by the RF host. The format of these

commands is described in the NFC Forum Digital Protocol specification.

Table 47. Commands issues by the RF host

Family command set Command name Instruction code

NFC-A technology

ALL_REQ

SENS_REQ

SDD_REQ

SEL_REQ

SLP_REQ

0x52

(1)

0x26

(1)

0x93 or 0x95 or 0x97

0x50

1. Code on 7 bits.

Note: In response to a SDD_REQ Command with a SEL_PAR value equal to 20h, the

ST25TA16Ks in the Operating Field transmit the requested cascade level of their NFCID1

(NFCID1 CLn, with n = 1 or 2). The NFCID1 of the ST25TA16K consists of 7 bytes. The length of the Response containing a complete NFCID1 cascade level (i.e., NFCID1 CL1, or

NFCID1 CL2) is always 5 bytes. The coding of the Response depends on the value of the

SEL_CMD byte and the size of the NFCID1.Refer to the example in

Table 48 for more

details.

Command

SDD_REQ 1

SEL_REQ 1

SENS_REQ or

ALL-REQ

Code

93 20

Table 48. Example of anticollision sequence

Comment

NVB 20

Number Valid bit

(2 bytes Code & NVB)

Response

ATQA

Code Comment

42 00

UID double size bit frame anticollision

CT uid1 uid2 uid3

BCC

CT Cascade Tag “0x88” (UID

7bytes)

BCC Block Check Character

(XOR previous Bytes)

93 70 CT uid1 uid2 uid3

BBC

NVB 70

(cmd NVB Uid lower bytes)

CT Cascade Tag “0x88”

SAK & CRC 04 DAD7 UID Not complete

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RF command sets ST25TA16K

Command

SDD_REQ 2

SEL_REQ 1

Table 48. Example of anticollision sequence (continued)

Code Comment

95 20

NVB 20

Number Valid bit

(2 bytes Code & NVB)

95 70 uid4 uid5 uid6 uid7

BBC

NVB 70

(cmd NVB Uid Upper bytes)

Response

Code Comment uid4 uid5 uid6 uid7

BCC

(UID 7bytes)

BCC Block Check Character

(XOR previous Bytes)

SAK & CRC 20 FC70 UID complete

RATS command and ATS response are used for NFC Forum Type 4A Tag Platform Device

Activation (as defined in NFC Forum Digital Protocol specification).

Table 49 details the RATS command. This command shall be sent after the anticollision

process.

Name

Byte field

Bit field

Instruction code

FSDI

DID (0 ≤ DID ≤ 14)

2 CRC bytes

INS

0xE0

Table 49. RATS command

Param

1 byte

b7-b4 b3-b0

CRC

2 bytes

The FSDI field codes the FSD, which defines the maximum size that an RF host is able to receive.

Table 50 gives the conversion from FSDI to FSD.

FSDI 0x0

FSD 16

0x1

Table 50. Conversion from FSDI to FSD

0x2 0x3 0x4 0x5 0x6 0x7 0x8

32 40 48 64 96 128 256

0x9h-

0xE

RFU

0xF

256

The DID (Dynamic ID, optionally affected to the ST25TA16K by the host to address

ST25TA16K in all commands) field defines the value of the addressed ST25TA16K. If DID is not ‘0’, the ST25TA16K will ignore the command if it contains a DID different from the one affected to it during RATS.

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ST25TA16K RF command sets

Name TL T0

Table 51. ATS response

TA(1)

Byte field 0x05 0x78 1 byte

Bit field -

Length of the ATS response

FSCI = 256 bytes

The maximum ascending data rate is 106 kbps

The maximum descending data rate is 106 kbps

FWI field (155 ms when TB = 0x90)

SFGI field (302 µs when TB = 0x90)

The DID is supported

2 CRC bytes

TB(1) b8-b5

1 byte b4-b1

TC(1)

0x02

CRC

2 bytes

The FSCI codes the FSC, which stands for the maximum frame size that the ST25TA16K is able to receive. The ST25TA16K is able to receive up to 256 bytes of command. If the RF host sends a command with more than 256 bytes, the ST25TA16K will not be able to treat the command and will not reply.

The FWI (Frame Waiting time Integer) codes the FWT, which stands for the Frame Waiting

Time. This time corresponds to the maximum duration while an RF host shall send before sending the next command.

The SFGI codes the SFGT, which stands for the Start-up Frame Guard Time. This is the minimum time that the reader shall wait after receiving the response of the ST25TA16K.

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RF command sets ST25TA16K

PPS (Protocol and Parameter Selection) command and response are defined in ISO/IEC

14443-4, in the Protocol Activation of PICC Type A.

The PPS command allows to change the data rates of the ascending (RF host to

ST25TA16K) and descending (ST25TA16K to RF host) data rates.

Name

Byte field

Bit field b7-b4

INS

Instruction code

DID

PPS1 is present -

RFU

PPS1 Descending data rate

Ascending data rate

2 CRC bytes

INS

0xDX

Table 52. PPS command

PPS0

0x11 b3-b0 0b0000

PPS1

1 byte b3-b2 b1-b0

CRC

2 bytes

The ascending and descending data rates shall be coded as described in

Table 53 .

Value

Data rate

Table 53. Ascending and descending data rate coding

0b00 0b01 0b10

106 kbps RFU RFU

0b11

RFU

When the ST25TA16K is able to change both data rates, it returns the response detailed in

Table 54 . The data rate of this response is 106 kbps; then, the ST25TA16K changes the

ascending and descending data rates.

Name

Byte field

Bit field

Response code

DID field

2 CRC bytes

Table 54. PPS response

INS -

0xDX b8-b5 b4-b1

PPS0

0x11

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ST25TA16K

6 RF device operation

6.1

RF device operation

Anticollision and Device Activation command set for the RF interface

The ST25TA16K device supports the command set defined in the NFC-A Technology and the Type 4A Tag Platform chapters of the NFC Digital Protocol V1.0 specification.

6.2 Open an RFsession

Once the RF host has terminated the anticollision procedure and retrieve the ATS response, it shall send the SelectApplication command. The ST25TA16K will open an RF session. At this point, the RF host can send the applicative command set.

6.3

6.4 Close an RFsession

The RF host can close the RF session by issuing one of these methods:

• send an S(DES) command

• turn off the RF field

Applicative command set

The applicative command set is composed of the following command sets:

• the NFC Forum Type 4 Tag command set

• the ISO/IEC 7816-4 command set

• the proprietary command set

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Functional procedures ST25TA16K

7.1

7.2

7.3

7.4

This section describes procedures to access the memory or to manage its protection.

Selection of an NDEF message

The RF host shall use this procedure to detect the NDEF message inside an ST25TA16K.

The NDEF detection procedure is as follows:

Open an RF session

2. Send the SelectNDEFTagApplication command

3. Select the CC file

4. Read the CC file

5. Select the NDEF file.

Reading of an NDEF message

The RF host executes the NDEF read procedure to read the NDEF file.

Detect successfully the NDEF file using the NDEF detection procedure

2. Check that the read access without any security is granted for the NDEF file from the information provided by the CC file

3. Select the NDEF file

4. Read the NDEF file.

Reading a locked NDEF file

The RF host executes this procedure to read an NDEF file that has been locked previously.

Select the NDEF Tag Application

2. Select the NDEF file

3. Verify the Read password by using the Verify command

4. Read the data in the NDEF file.

Locking an NDEF file

The RF host executes this procedure to protect an NDEF file.

Select the NDEF Tag Application

2. Check the right access provided by the CC file

3. Select the NDEF file

4. Transmit the NDEF file Write password by using the Verify command

5. Lock the NDEF file by sending the Enable verification command.

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7.5

Functional procedures

Unlocking an NDEF file

The RF host executes this procedure to read an NDEF file that has been locked previously.

Select the NDEF Tag Application

2. Select the NDEF file

3. Verify the NDEF file Write password by using the Verify command

4. Unlock the NDEF file by sending the Disable verification command

7.6 Reaching the read-only state for an NDEF file

The RF host executes this procedure to read an NDEF file that has been locked previously.

Select the NDEF Tag Application

2. Select the NDEF file

3. Transmit the NDEF file Write password using the Verify command

4. Send an EnablePermanentState command

7.7

7.8 Creating or updating an NDEF file

Select the NDEF Tag Application

2. Select the NDEF file

3. Set the File Length to 0x00 using the UpdateBinary command

4. Write NDEF message content using the UpdateBinary command

5. Set the new File Length (must be always two written bytes), and elect the NDEF Tag

Application

Changing the file type (applicable only on file 0x0001)

The RF host executes this procedure to change the File Type of a file for which all access rights were previously granted.

Select the NDEF Tag Application

2. Select the file 0x0001

3. Set the File Length to 0x00 using the UpdateBinary command

4. Send an UpdateFileType command with the New file Type as data.

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UID: Unique identifier ST25TA16K

The ST25TA16K is uniquely identified by a 7 bytes unique identifier (UID). The UID is a read-only code and comprises:

• The IC manufacturer code on 1 byte (0x02 for STMicroelectronics).

• The Product code on 1 byte.

• A device number on 5 bytes.

Table 55 describes the UID format.

Table 55. UID format

0x02 0xC5 5 bytes

IC manufacturer code

ST25TA16K product code

Device number

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ST25TA16K Maximum ratings

Stressing the device above the ratings listed in

Table 56

may cause permanent damage to the device. These are stress ratings only and operation of the device at these or any other conditions above those indicated in the operating sections of this specification is not implied.

Exposure to absolute maximum rating conditions for extended periods may affect the device reliability.

Symbol

STG t

STG

Table 56. Absolute maximum ratings

Parameter Min.

Ambient operating temperature

Storage temperature

Storage time

Sawn wafer on

UV tape (kept in its original packing form)

-40

Max.

(1)

Unit

°C

°C months

STG t

STG

(3)

MAX_1

MAX_2

ESD

(3)

Storage temperature

Storage time

Sawn bumped wafer (kept in its antistatic bag)

RF supply current AC0 - AC1

RF input voltage amplitude between AC0 and AC1,

GND pad left floating

VAC0-VAC1

AC voltage between AC0 and GND, or AC1 and GND

VAC0-GND or

VAC1-GND

Electrostatic discharge voltage

(human body model)

(4)

AC0-AC1

Electrostatic discharge voltage

(Machine model)

-0.5

(2)

100

4.5

1000

200

1. Counted from ST shipment date.

2. Counted from ST production (taping) date.

3. Based on characterization, not tested in production. Maximum absorbed power = 100 mW at 7.5 A/m.

4. AEC-Q100-002 (compliant with JEDEC Std JESD22-A114A, C1 = 100 pF, R1 = 1500 Ω , R2 = 500 Ω ).

°C months mA

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RF electrical parameters

10 RF electrical parameters

ST25TA16K

This section summarizes the operating and measurement conditions, and the DC and AC characteristics of the device in RF mode.

The parameters in the DC and AC characteristics tables that follow are derived from tests performed under the Measurement Conditions summarized in the relevant tables.

Designers should check that the operating conditions in their circuit match the measurement conditions when relying on the quoted parameters.

Symbol

Table 57. Default operating conditions

Parameter Min.

Ambient operating temperature –40

Max.

Unit

°C

Symbol Parameter

Table 58. RF characteristics

(1)

Condition Min Typ Max Unit f

H_ISO

H_Extended

External RF signal frequency

Operating field according to ISO

Operating field in extended temperature range

= 0 °C to 50 °C

= -40 °C to 85 °C

13.553

1500

13.56

13.567

7500

CARRIER t

1 t

2 t

3 t

100% carrier modulation index

Pause A length

Pause A low time

Pause A rise time

Pause A rise time section

MI=(A-B)/(A+B)

28/f

7/f

1.5xt4

MIN CD

Minimum time from carrier generation to first data

From H-field min -

W t

RF write time (including internal

Verify) for one page

Internal tuning capacitor in SO8

(2)

TUN t

RF_OFF

RF OFF time f

= 13.56 MHz

Chip reset

22.5

1. All timing characterizations were performed on a reference antenna with the following characteristics:

External size: 75 mm x 48 mm

Number of turns: 6

Width of conductor: 0.6 mm

Space between two conductors: 0.6 mm

Value of the tuning capacitor in SO8: 25 pF (ST25TA16K)

Value of the coil: 5 µH

Tuning frequency: 14.2 MHz.

2. Characterized only, at room temperature only, measured at VAC0-VAC1 = 1 V peak to peak, at 13.56 MHz.

100

40.5/f

C t1

16/f

6/f

27.5

MHz mA/m mA/m ms ms pF ms

µs

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ST25TA16K Ordering information

Device type

ST25 = RF memory

Table 59. Ordering information scheme for packaged devices

ST25 T A

Product Type

T = Tags + RFID

Protocol

A = ISO14443-A

Memory density

16K (binary)

Interface

A = None

Features

B = Basic features (no option)

Operating temperature

6 = -40 o

C to +85 o

Package / Packing

G = Bumped 120 µm

Capacitor value

3 = 25 pF

Note: Parts marked as “ES”, “E” or accompanied by an Engineering Sample notification letter, are not yet qualified and therefore not yet ready to be used in production and any consequences deriving from such usage will not be at ST charge. In no event, ST will be liable for any customer usage of these engineering samples in production. ST Quality has to be contacted prior to any decision to use these Engineering samples to run qualification activity.

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Revision history ST25TA16K

Date

05-May-2015

31-Aug-2016

21-Oct-2016

16-Feb-2017

Revision

Table 60. Document revision history

Changes

Initial release.

Updated Description and image on Cover page.

Updated Figure 2: Changing the read access right to an NDEF file and

Figure 3: Changing the write access right to an NDEF file .

Added Section 5.8.3: UpdateFileType command

Updated Section 5.9.2: RATS command and ATS response ,

Section 5.9.3: PPS command and response ,

Section 7.6: Reaching the read-only state for an NDEF file , Section 7.7: Creating or updating an

NDEF file and Section 7.8: Changing the file type (applicable only on file

0x0001)

Updated Table 9: RF command sets

, Table 10: I-Block format ,

Table 16:

S-Block format ,

Table 41: C-APDU of the ExtendedReadBinary command and

Table 59: Ordering information scheme for packaged devices

Updated Table 56: Absolute maximum ratings and added footnote 2 .

Updated title of

Table 50: Conversion from FSDI to FSD and of

Section 11: Ordering information .

Updated Features

Section 3.4: NDEF file passwords

Section 5.9.1:

Anticollision command set

and Section 5.9.2: RATS command and ATS response .

Updated Table 4: CC file layout for one NDEF file ,

Table 5: NDEF file layout and Table 6: Field list

Added Table 48: Example of anticollision sequence .

Removed former footnote 1

from Table 6: Field list .

Updated footnote

Table 58: RF characteristics

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ST25TA16K

IMPORTANT NOTICE – PLEASE READ CAREFULLY

STMicroelectronics NV and its subsidiaries (“ST”) reserve the right to make changes, corrections, enhancements, modifications, and improvements to ST products and/or to this document at any time without notice. Purchasers should obtain the latest relevant information on

ST products before placing orders. ST products are sold pursuant to ST’s terms and conditions of sale in place at the time of order acknowledgement.

Purchasers are solely responsible for the choice, selection, and use of ST products and ST assumes no liability for application assistance or the design of Purchasers’ products.

No license, express or implied, to any intellectual property right is granted by ST herein.

Resale of ST products with provisions different from the information set forth herein shall void any warranty granted by ST for such product.

ST and the ST logo are trademarks of ST. All other product or service names are the property of their respective owners.

Information in this document supersedes and replaces information previously supplied in any prior versions of this document.

DocID027786 Rev 4 47/47

ડાઉનલોડ કરો

માત્ર એક મૈત્રીપૂર્ણ રીમાઇન્ડર. તમે અહીં જ દસ્તાવેજ જોઈ શકો છો. પરંતુ સૌથી મહત્વપૂર્ણ બાબત એ છે કે, અમારા AI એ તેને પહેલેથી જ વાંચી લીધો છે. તે જટિલ બાબતોને સરળ શબ્દોમાં સમજાવી શકે છે, કોઈપણ ભાષામાં તમારા પ્રશ્નોના જવાબ આપી શકે છે અને તમને સૌથી લાંબા અથવા સૌથી જટિલ દસ્તાવેજોને પણ ઝડપથી નેવિગેટ કરવામાં મદદ કરી શકે છે.

ના, હું હજી પણ જાતે જ શોધવા માંગુ છું

નમસ્તે! હું એક AI ચેટબોટ છું જે ખાસ કરીને STMicroelectronics ST25TA16K Datasheet સાથે તમને સહાય કરવા માટે તાલીમ પામેલો છે. મેં દસ્તાવેજની સંપૂર્ણ સમીક્ષા કરી છે અને તમને જરૂરી ચોક્કસ માહિતી શોધવામાં અથવા સ્પષ્ટ અને સરળ શબ્દોમાં સામગ્રી સમજાવવામાં મદદ કરી શકું છું. પછી ભલે તમે ચોક્કસ સુવિધાઓ, મુશ્કેલીનિવારણ પગલાં અથવા સામાન્ય વપરાશ વિશે માર્ગદર્શન શોધી રહ્યા હોવ, તમારા પ્રશ્નો પૂછવા માટે નિઃસંકોચ રહો. તમે તમારી ચિંતાઓ અથવા જરૂરિયાતો વિશે જેટલી વધુ વિગતો પ્રદાન કરશો, તેટલી વધુ ચોક્કસ અને અસરકારક રીતે હું તમને સહાય કરી શકું છું!