Datasheet

Payload Length

Indicates the length (in bytes) of the record payload. If the SR field (described above) is set to 1 in the record header,

this value will be one byte long (for a payload length from 0-255 bytes). If the SR field is set to 0, this value will be a 32-

bit value occupying 4 bytes.

ID Length

Indicates the length in bytes of the ID field. This field is present only if the IL flag (described above) is set to 1 in the

record header.

Record Type

This value describes the 'type' of record that follows. The values of the type field must corresponse to the value

entered in the TNF bits of the record header.

Record ID

The value of the ID field if an ID is included (the IL bit in the record header is set to 1). If the IL bit is set to 0, this field is

ommitted.

Payload

The record payload, which will be exactly the number of bytes described in the Payload Length field earlier.

Well-Known Records (TNF Record Type 0x01)

Probably the most useful record type is the "NFC Forum Well-Known Type" (TNF Type 0x01). Record types that adhere

to the "Well-Defined" type are each described by something called an RTD or Record Type Definition. Some of the

current Well-Defined RTDs are:

URI Records (0x55/'U')

The "Well Known Type" for a URI record is 0x55 ('U'), and this record type can be used to store a variety of useful

information such as telephone numbers (tel:), website addresses, links to FTP file locations, etc.

URI Records are defined in the document "URI Record Type Definition" from the NFC Forum, and it has the following

structure:

The URI Identifier Code is use to shorten the URI length, and can have any of the following values:

Name Offset Size Description

---- ------ ---- -----------

Identifier Code 0 1 byte See table below

URI Field 1 N bytes The rest of the URI (depending on byte 0 above)