ST AN3408 APPLICATION NOTE
AN3408
Application note
Using LRIxx, LRISxx and M24Lxx-R products as NFC vicinity tags
Introduction
The NFC technology allows accessing standard ISO/IEC 15693 products such as
STMicroelectronics Dual interface EEPROMs (M24LR04E-R, M24LR16E-R and
M24LR64E-R) and ST ISO/IEC 15693 RFID tag products (LRI1K, LRI2K, LRIS2K and
LRIS64K).
The NFC forum specifies a data structure standard named NDEF allowing user data
exchange. Data can be either text, URI or picture.
RFID or NFC tag memory can embed NDEF messages and share it with different hosts
(reader, mobile phone).
This application note explains how to apply the NDEF format to STMicroelectronics ISO/IEC
15693 products (LRI1K, LRI2K, LRIS2K, LRIS64K and M24LR64-R).
Reference documents
■ ISO/IEC standards
– [15693-3]: ISO/IEC 15693-3: Identification cards - Contactless integrated circuit(s)
cards - Vicinity cards - Part 3: Anti-collision and transmission protocol
■ NFC forum documents
– [NDEF]: NFC Data Exchange Format (NDEF) Technical Specification; NFC Forum™;
NDEF 1.0
– [URI]: URI Record Type Definition document; NFC Forum™
– [RTD] : NFC Record Type Definition; NFC forum
– [BLUETOOTH] : Bluetooth Secure Simple Pairing Using NFC; NFC forum
– [TEXT] : Text Record Type Definition; NFC forum
– [TAG-2]: Type 2 Tag Operation Technical Specification; NFC Forum™; 1.1
■ ST documents
– LRI1K datasheet
– LRI2K datasheet
– LRIS2K datasheet
– LRIS64K datasheet
– M24LR64-R datasheet
Ta bl e 1 lists the products concerned by this application note.
Table 1. Applicable products
Type Applicable products
Dual interface EEPROMs M24LR04E-R, M24LR16E-R and M24LR64E-R
RFID & RF Memory ICs LRI1K, LRI2K, LRIS2K and LRIS64K
July 2012 Doc ID 018867 Rev 2 1/37
www.st.com
Contents AN3408
Contents
1 Memory organization for STMicroelectronics
ISO/IEC 15693 products . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
1.1 User memory area . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
1.2 DSFID and AFI system area . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
1.3 Unique identifier . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
1.4 Protection system . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
2 NDEF data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
2.1 Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
2.2 Capability container field . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
2.3 NDEF message using TLV format . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
2.3.1 T field values . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
2.3.2 L field format . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
2.3.3 V field: NDEF message . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
2.3.4 Specific TLV field . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
3 Storing an NDEF message in STMicroelectronics
ISO15693 products . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
3.1 Memory organization of LRI1K, LRI2K and LRIS2K . . . . . . . . . . . . . . . . 14
3.2 Memory organization of LRIS64K and M24LRxx devices . . . . . . . . . . . . 14
3.2.1 Description of the first sector . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
3.3 CC2 value . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
4 Example of NDEF record . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
4.1 Text record . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
4.1.1 Memory mapping for text record type on LRI2K . . . . . . . . . . . . . . . . . . 17
4.2 URI record . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
4.2.1 Memory mapping for URI record message on LRI2K . . . . . . . . . . . . . . 18
4.3 Smart poster record . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
4.3.1 Title record . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
4.3.2 URI record . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
4.3.3 Action record . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
4.3.4 Icon record . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
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AN3408 Contents
4.3.5 Size record . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
4.3.6 Type record . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
4.3.7 Example of a smart poster record composed of a Title and a URI . . . . 19
4.3.8 Memory mapping of the smart poster record . . . . . . . . . . . . . . . . . . . . . 21
4.4 vCard record . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
4.5 Bluetooth record . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
4.5.1 Memory mapping of an M24LR64E-R EEPROM . . . . . . . . . . . . . . . . . . 26
4.5.2 Simplified Bluetooth record for a single carrier wave . . . . . . . . . . . . . . . 27
4.5.3 Memory mapping of an M24LR64E-R EEPROM . . . . . . . . . . . . . . . . . . 28
5 User application flow charts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
5.1 ISO/IEC 15693 contactless tag identification flow chart . . . . . . . . . . . . . . 29
5.2 Reading an NDEF message in an ISO/IEC 15693 contactless tag . . . . . 30
5.3 WRITING an NDEF message in an ISO/IEC 15693 contactless tag . . . . 31
5.4 Identifying a blank card ISO/IEC 15693 contactless tag . . . . . . . . . . . . . 31
5.5 Programming an NDEF message in an ISO/IEC 15693 contactless tag . 33
Appendix A Acronym and notational conventions . . . . . . . . . . . . . . . . . . . . . . . 34
A.1 Representation of numbers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
Revision history . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
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List of tables AN3408
List of tables
Table 1. Applicable products . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Table 2. Access rights to memory fields . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Table 3. ST ISO/IEC 15693 memory size. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Table 4. UID field description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Table 5. IC product code for ISO15639 STMicroelectronics products . . . . . . . . . . . . . . . . . . . . . . . . 7
Table 6. ST ISO/IEC 15693 sector size . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Table 7. Capability container field description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Table 8. Read access condition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Table 9. Write access condition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Table 10. CC field example . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Table 11. TLV format description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Table 12. T field values and description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Table 13. L field byte format . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Table 14. Record head byte fields description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Table 15. Type name format field values . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Table 16. Example of a record head byte structure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Table 17. NULL TLV field description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Table 18. Terminator TLV description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Table 19. Storing an NDEF message in LRI1K, LRI2K and LRIS2K . . . . . . . . . . . . . . . . . . . . . . . . . 14
Table 20. Storing an NDEF message in LRIS64K and M24LRxx. . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Table 21. First sector details on M24LR64-R . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
Table 22. CC2 value for ISO/IEC 15693 products . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
Table 23. “ISO15693 as NFC tag” NDEF message structure. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Table 24. LRI2K memory mapping for “ISO15693 as NFC tag” NDEF message. . . . . . . . . . . . . . . . 17
Table 25. URI record message structure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
Table 26. LRI2K memory mapping for URI record message “http://www.st.com” . . . . . . . . . . . . . . . 18
Table 27. List of available actions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Table 28. Smart poster record with a Title and a URI. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Table 29. NDEF message . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Table 30. Record header = 0xD1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Table 31. URI record . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Table 32. Text record . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Table 33. Memory mapping of the smart poster record . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Table 34. vCard information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Table 35. Record header = 0xC2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Table 36. Bluetooth record . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
Table 37. Handover select record. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
Table 38. Record header = 0x91 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
Table 39. Alternative carrier record . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
Table 40. Record header = 0xD1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
Table 41. Bluetooth carrier configuration record. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
Table 42. Record header = 0x5A . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
Table 43. Memory mapping of an M24LR64E-R EEPROM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
Table 44. Simplified Bluetooth record for a single carrier wave . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
Table 45. Record header = 0xD2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
Table 46. Memory mapping of an M24LR64E-R EEPROM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
Table 47. Contactless tag response of GetSystemInformation command . . . . . . . . . . . . . . . . . . . . . 32
Table 48. List of acronyms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
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AN3408 List of tables
Table 49. Document revision history . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
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Memory organization for STMicroelectronics ISO/IEC 15693 products AN3408
1 Memory organization for STMicroelectronics
ISO/IEC 15693 products
The ST ISO/IEC 15693 contactless tag (LRI1K, LRI2K, LRIS2K, LRIS64K) and the dual
interface memory (M24LR04E-R, M24LR16E-R and M24LR64E-R) is divided into three
different areas:
● User memory area, where the user can read and write data.
● System area, which contains UID, DSFID and AFI fields.
● Protection system area, which contains the user memory area protection.
Access rights to the different memory fields are given in Ta bl e 2 .
Table 2. Access rights to memory fields
Operation
R e a d Ye s Ye s Ye s Ye s
Write Yes No Yes Yes
Lock Yes
User memory
area
For more details on the protection system, refer to the corresponding STMicroelectronics
datasheet.
1.1 User memory area
The user memory stores NDEF messages. This area can be write-protected by the user.
The user memory size depends on ISO/IEC 15693 contactless tag, as shown in Ta bl e 3 .
Table 3. ST ISO/IEC 15693 memory size
User memory
size
LRI1K LRI2K LRIS2K LRIS64K M24LR04E-R M24LR16E-R M24LR64E-R
kbit 2 kbits 2 kbits 64 kbits 2 kbits 16 kbits 64 kbits
1
128 bytes 256 bytes 256 bytes 8192 bytes 512 bytes 2048 bytes 8192 bytes
System area
UID DSFID and AFI
Locked by IC
manufacturer
Protection
system
Ye s N A
First RF block 0 0 0 0 0 0 0
Last RF block 31 63 63 2047 127 511 2047
NDEF memory
size
1. NDEF memory size includes User area and CC field memory area.
2. If NDEF message size exceeds 2040 bytes, bit 2 of CC3 shall be set (see Chapter 2.2: Capability container field).
128 bytes
(1)
256 bytes
(1)
256 bytes
(1)
8192 bytes
(1) (2)
512 bytes
(1)
2048 bytes
(1) (2)
8192 bytes
(1) (2)
Note: M24LR64E-R and M24LR16E-R have a specific format for read and write commands. Their
block number is coded on two bytes instead of one. For more details, refer to LRIS64K,
M24LR16E-R and M24LR64E-R datasheets.
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AN3408 Memory organization for STMicroelectronics ISO/IEC 15693 products
1.2 DSFID and AFI system area
For more details on DSFID and AFI system area, please refer to the corresponding
STMicroelectronics datasheet.
1.3 Unique identifier
The unique identifier (UID) is an 8-byte field used to identify an IC. The UID is defined by the
IC manufacturer and is write-protected.
The UID bytes are given in Ta bl e 4 . The first byte value is fixed to 0xE0, and the second byte
value contains the IC manufacturer code.
Table 4. UID field description
UID 7 UID 6 UID 5 UID 4-0
0xE0 IC manufacturer code IC product code
Contactless tag unique
number
Note: The IC manufacturer code of STMicroelectronics is 0x02 on 8 bits (refer to [15693-3] – on
page 1).
Table 5. IC product code for ISO15639 STMicroelectronics products
UID 5
(1 byte)
1. M24LR64-R and LRIS64k have an extended addressing mode; refer to product datasheet.
LRI1K LRI2K LRIS2K
LRIS64
(1)
K
M24LR64-
(1)
R
M24LR04
E-R
M24LR64
E-R
M24LR16
E-R
0b010000xx 0b001000xx 0b001010xx 0x44 0x2C 0x2C 0x2C 0x4E
1.4 Protection system
The user memory area of ISO/IEC 15693 STMicroelectronics products can be writeprotected. The granularity of the protection can be either 4 bytes or 128 bytes as defined in
Ta bl e 6 below.
Table 6. ST ISO/IEC 15693 sector size
LRI1K LRI2K LRIS2K LRIS64K M24LR4E-R
M24LR16E-RM24LR64
E-R
Memory block
size
4 bytes 128 bytes
For more details on the protection system, please refer to the corresponding
STMicroelectronics datasheet.
● The LRIS64K and M24LRxx memory write-protected granularity is the sector.
● The LRI1K, LRI2K and LRIS2K memory write-protected granularity is the block.
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NDEF data AN3408
2 NDEF data
NDEF, which stands for NFC data exchange, is a data format defined by the NFC forum.
This format defines a message encapsulation format to exchange information between a
reader and a contactless tag.
NDEF can be used to exchange different types of information such as text, URI and others.
This chapter details NDEF for the following types of information:
● text
● URI
● vCard, which is a virtual business card
● Bluetooth, that allows to carry out the pairing between two bluetooth devices.
2.1 Overview
NDEF data is composed of:
● Capability container
● TLV field, which includes the NDEF message.
The TLV field is located after the CC field. The size of a TLV field is computed according to
the CC2 byte value.
2.2 Capability container field
The Capability container field (CC field) is a 4-byte field that contains an identification value
used to store an NDEF message. The signification of each byte is explained in Tab l e 7.
Table 7. Capability container field description
Byte name
CC0 0 0xE1 7:0 NDEF message is present into memory (called magic number)
CC1 1 0xXX
CC2 2 0xXX 7:0 Memory size of data field and CC field in bytes (= CC2 * 8)
CC3 3 0x0X
number
Byte
Value Bit Function
7:6 Major version number
5:4 Minor version number
3:2 Read access condition
1:0 Write access condition
7:3 RFU
2
1RFU
0
1: the IC memory size exceeds 2040 bytes (CC2 overflow)
0: the IC memory size is only defined by CC2 value
1: IC supports ReadMultipleBlocks Command
0: IC does not support ReadMultipleBlocks Command
(1)
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AN3408 NDEF data
1. If bit number 2 of CC3 is set, the memory size exceeds 2040 bytes (CC2 overflow). The real memory size can be obtained
with the GetSystemInformation command. For more information about the GetSystemInformation command, refer to the
corresponding STMicroelectronics datasheet.
Read access condition values defined by bit 3 and bit 4 of CC1 byte are described in
Ta bl e 8 .
Table 8. Read access condition
Read access condition value Description
0b00 Free read access
0b01 RFU
0b10 RFU
0b11 RFU
Write access condition values defined by bit 0 and bit 1 of CC1 byte are described in
Ta bl e 9 . Write access condition values depend on the product. For more details, refer to the
corresponding STMicroelectronics datasheet.
Table 9. Write access condition
Write access
condition value
Description LRI1k, LRI2k
LRIS2k, LRIS64k,
0b00 Free write access Yes Yes
0b01 RFU No No
0b10
Write password access (data can be
written after sending a password)
No Yes
0b11 No write access Yes Yes
Note: Bit 2 and bit 3 of CC1 byte (read access values) shall be reset to 0b00 value.
The user shall set the write protection bit according to bit 0 and bit 1 of CC1 byte. For more
details, refer to the definition of the lock command in the corresponding STMicroelectronics
datasheet.
M24LR64-R
Doc ID 018867 Rev 2 9/37
NDEF data AN3408
Example 1
Table 10. CC field example
Byte name Value Bit Function
CC0 0xE1 7:0 Magic number
7:6 Major version number: 0b01
5:4 Minor version number: 0b00
CC1 0x40
3:2 Read access condition: 0b00 (free read access)
1:0 Write access condition: 0b00 (free write access)
CC2 0x10 7:0 Data field and CC field size = 16*8 = 128 bytes
CC3 0x00 7:0 IC does not support Read multiple block
2.3 NDEF message using TLV format
A TLV format is a generic data structure used to embed information and to store NDEF
messages. The TLV format is composed of three fields:
● Type field (T)
● Length field (L)
● Value field (V): contained user message.
Table 11. TLV format description
Length (bytes) 1 1 or 3L field value
Data description
For more information on the TLV format, refer to [TAG-2] NFC forum – on page 1.
2.3.1 T field values
Ta bl e 1 2 below lists the T field values as defined by the NFC forum.
Table 12. T field values and description
TLV block name T field value Description
NULL TLV 0x00 Used to padding.
Lock control TLV 0x01 It defines details of the lock bits.
Memory control TLV 0x02 It identifies reserved memory areas.
NDEF message TLV 0x03 It contains NDEF message.
Proprietary TLV 0xFD Tag proprietary information.
Terminator TLV 0xFE Last TLV block in the data area.
T field L field V field
Type of TLV block,
see Ta bl e 12
Number of bytes of
V field
Data
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2.3.2 L field format
The L field can be either coded on 1 or 3 bytes, as shown in Ta bl e 1 3.
Table 13. L field byte format
Byte format Byte number Value
1 1 0x00 to 0xFE
3
1. The 0xFF FFFF value is the concatenation of the bytes 0xFF and 0xFFFF.
2.3.3 V field: NDEF message
The V field is composed of a record head byte, the NDEF message and TLV terminator. The
record head byte is described in a): Record head byte.
An application example is given to illustrate a TLV field: it is a URL, as specified in the “URI
Record Type Definition” document (NFC forum). see Chapter 4.2: URI record.
a) Record head byte
An NDEF message can contain 1 or more NDEF records. The record head byte gives some
information on the current NDEF record.
The different fields of record head byte are described in Ta bl e 1 4.
Table 14. Record head byte fields description
Name Bit Function
MB (message begin) 7
10xFF
3 0x00FF to 0xFFFE
(1)
1: This record is the first of NDEF message.
0: This record is not the first of NDEF message.
ME (message end) 6
1: This record is the last of NDEF message.
0: This record is not the last of NDEF message.
1: this record is the initial or middle record chunk.
CF (chunk flag) 5
0: this record is the terminating record chunk.
SR (short record) 4
1: the payload
0: the payload
(1)
length is on one byte.
(1)
length is more than one byte.
1: ID length field is present.
IL (ID_length flag) 3
0: ID length field is omitted.
TNF 2:0 TNF indicates the structure of the type field (see Ta bl e 1 5 ).
1. Payload is NDEF message body.
b) Type name format field values
The type name format (TNF) is a 3 bits value that indicates the structure of the value of the
type field.
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Table 15. Type name format field values
Type name format Value
Empty
0b000
NFC forum well known type 0b001
Media type as defined in RFC 2046 0b010
Absolute URI as defined in RFC 3986 0b011
NFC forum external type 0b100
Unknown 0b101
Unchanged 0b110
Reserved 0b111
Example 1
This record head defines an NDEF message which is composed of one record
(MB = ME = 1).
Table 16. Example of a record head byte structure
Record
head byte
0xD1 11010001
Type record
head byte
MB ME CF SR IL TNF
This is the first record
This is the last record
This record is the termination chunk
The payload length size in on one byte
The ID length is omitted
NFC forum well known type
For more information about the record head byte, refer to the NDEF data exchange format
(NDEF) document.
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