NFC Data Exchange Format Decoded: The Essential Startup Handbook for Connectivity

NFC Data Exchange Format Decoded

Near Field Communications Technology (NFC) has revolutionized the way business transactions work. Its contactless communication capability introduces a new level of efficiency and convenience. That’s why businesses are now shifting to adopt NFC technology.

 

To integrate NFC, you should use the NFC Data Exchange Format (NDEF). This format serves as a standardized data format. NFC Communication Standards ensure NFC technology to interact with all compatible devices. With this tag format, you can easily make transactions possible in one simple scan.

In this article, we’ll discuss the fundamental NDEF components and how information is encoded. We’ll also provide instructions for implementing basic writing operations using mobile applications.

 

What is NDEF?

What is NDEF

NFC Data Exchange Format (NDEF) is a standardized protocol that regulates NFC tag encoding. This protocol is used when exchanging data between NFC devices and tags. With NDEF, business owners can write specific data structures into the NFC chips.

 

The two NFC protocol specifications being followed are ISO/IEC 14443 and ISO/18000-3. The first standard determines the ID cards used for storing information. The latter standard is the RFID Communication Standards that are used by NFC devices.

 

The RFID standards state how NFC cards communicate at a frequency of 13.56MHz. It also states that the NFC uses a proximity-based data exchange. They must operate within 4cm to transmit information.

 

Because of these standards, NFC-enabled devices can perform wireless data transfer methods. With an NFC chip and a reader device, you can initiate contactless data sharing.

 

Basic Components of NDEF Record

Basic Components of NDEF Record

NDEF Message and Records

NDEF is composed of an NDEF Message and NDEF Records. NFC devices and tags communicate using messages. These messages are composed of one or more NDEF Records like Figure 1 below.

NDEF Message and Records

Figure 1. NDEF Message and Records

NDEF Records are more specific. They contain a structure that identifies the content of your message. To put it simply, imagine the message to be a letter you sent. The Records would be the different parts of the letter.

For a more specific example, the message can be your contact information. The Records would include your contact name, phone number, and address.

Key Fields in an NDEF Record Header

Each NDEF Record is composed of a Record Header and A Record Payload. A Record Header contains metadata fields that pertain to the Record. The Payload, on the other hand, is the content of the message.

 

In Figure 2, one of the Records contains your contact name. Below that, the Record header such as Payload length will be indicated. Whereas, the Record Payload will show your full name, Jane Doe.

Composition of NDEF Record

Figure 2. Composition of NDEF Records with a Record of contact name

 

The NDEF Record Header is composed of metadata that describes your Record. Seven metadata can be displayed. However, they might vary depending on the type of information that will be written.

 

Figure 3 shows a diagram of the different fields of the NDEF Record Header.

Figure 3. Key Fields in the NDEF Record Header

 

Figure 3. Key Fields in the NDEF Record Header

Type Name Format Field (TNF)

The TNF describes what type of data the Record has. The TNF is usually defined by numbers 0-7 which corresponds to values.

 

0- Empty– This means that your Record has no type, ID, or Payload

1- Well-Known– This means that the Record is defined by the Record Type Definition (RTD)

2- MIME media type– This means that the Record is an internet media type

3- Absolute URI– This means that the Record is an absolute URI

4- External– This means that the Record is user-defined based on RTD specification

5- Unknown– This means that the Payload is unknown

6- Unchanged– This means that the Payload is the middle and terminating Records of chunked Payloads

7- Reserved This is reserved by the NFC Forum

Bit Flags

Bit flags are indicators of the Record’s location in your message

MB- Message Begin

MB indicates that this is the start of the NDEF Message

ME- Message End

ME indicates that this is the last Record in the NDEF Message

CF Chunk Flag

CF Indicates that this is the first or middle Record chunk

SR- Short Record

SR means that one Payload length is 1 byte

IL- ID Length

IL indicates if the Length Field is present

Type Length

The type length is the field that indicates the length of the Record type. This field often has a value of zero.

Payload Length

Payload length measures the length of the Record Payload. If the Payload is JANE DOE, the Payload length will be measured in bytes.

ID Length

The ID length is optional. It is only present if the ID Length flag has a value of 1. Otherwise, it will not appear.

Record Type

The Record Type is the one that describes the Record. Its format can be, MIME media types, ERI, or text.

Record ID

This field is also optional. If the ID is present and set to 1, then it is included. However, if it is set to 0, then this field is omitted.

What is a Payload?

The Payload is the content of your message. It can be a text, a link, or an image. It will be displayed as long as it fits in the stream of bytes. If your message is your business address, you can input a map link. This will direct your customers to your business map link.

 

Writing NDEF Records to NFC Tags

Writing NDEF Records to NFC Tags

With NFC’s mobile data exchange format, writing NDEF Records into NFC tags got easier. All you need are blank tags in NDEF format and a smartphone. Most smartphones are capable of reading NFC.

Using Apps to Write NDEF Records on NFC Tags

For this example, we’ll illustrate how to launch your business address using NFC tags. With the use of NFC Technology Applications, we can encode the URL. Smartphones can read NFC devices because of NFC’s smart device connectivity standards.

 

Here are apps that can help you encode NFC tags using a mobile device

  1. Android
    1. NFC TagWriter by NXP
    2. NFC Tools
  2. iOS
    1. NFC Tools
    2. NFC TagWriter by NXP
    3. Smart NFC

Once you have these apps downloaded, you can proceed with these steps. We’ll be using the NFC tools for encoding.

 

Step 1: Open your NFC Tools app and tap the option READ

Step 2: In the menu, choose WRITE

Step 3: Then click on ADD Record to input your information

Step 4: In this app, you have a lot of options for the kind of data you want to add. For this next step, click ADDRESS.

Step 5: Paste your full address in the lower field

Step 6: On the upper field, click the orange EDIT button. Then choose from the types of maps available.

Step 7: Click Apple Plans or Google Maps and click OK

Step 8: Click the WRITE button once more and this will prompt “Ready to Scan” on your phone.

Step 9: Scan your blank NFC tag and wait for a check mark to indicate successful writing.

Key Points

NFC and the use of NDEF have opened new possibilities for businesses and individuals. This technology has made it possible to encode and share information seamlessly. The current capability of most smartphones to read and write on NFC shows its immense potential.

 

As we continue to advance in contactless communication, data exchange will further improve.

Let’s unlock the opportunities and potentials presented by the NFC. As we explore and learn about this technology, we can collectively shape the future of information exchange.

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