This information applies to the nRF52 Series only.

To program a tag, use the precompiled Type 2 Tag library.

Complete the following steps:

1. Implement a callback function that handles events from the Type 2 Tag library and register it:

   
            uint32_t  err_code;
           
   
            
             NfcRetval
            
            ret_val;
           
   
           
   
            
             /* Callback for NFC events */
            
           
   
            
             void
            
            nfc_callback(
            
             void
            
            *context,
            
             NfcEvent
            
            event,
            
             const
            
            
             char
            
            *data,
            
             size_t
            
            dataLength)
           
   
            {
           
   
            ...
           
   
            }
           
   
           
   
            
             /* Set up NFC and register application callback for NFC events. */
            
           
   
            ret_val =
            
             nfcSetup
            
            (nfc_callback, NULL);
           
   
            
             if
            
            (ret_val != NFC_RETVAL_OK)
           
   
            {
           
   
            
             APP_ERROR_CHECK
            
            ((uint32_t) ret_val);
           
   
            }
           

   The NFCT interrupt handler runs at priority level APP_LOW.
   
   
2. Configure the data for the tag. You can provide the data as NDEF message (recommended, see NFC Data Exchange Format ) or as a raw TLV structure (advanced usage, see Type 2 Tag data format ).
   • Set an NDEF message:

     
                uint8_t ndef_msg_buf[] = ...;
                
                 // Buffer with the user NDEF message
                
               
     
                uint32_t len           =
                
                 sizeof
                
                (ndef_msg_buf);
               
     
               
     
                
                 /* Set created message as the NFC payload. */
                
               
     
                ret_val =
                
                 nfcSetPayload
                
                ( (
                
                 char
                
                *)ndef_msg_buf, len);
               
     
                
                 if
                
                (ret_val != NFC_RETVAL_OK)
               
     
                {
               
     
                
                 APP_ERROR_CHECK
                
                ((uint32_t) ret_val);
               
     
                }
               

   • Alternatively, set a TLV structure:

     
                uint8_t tlv_buf[] = ...;
                
                 // Buffer with the user TLV structure
                
               
     
                uint32_t len           =
                
                 sizeof
                
                (tlv_buf);
               
     
               
     
                
                 /* Set created message as the NFC payload. */
                
               
     
                ret_val =
                
                 nfcSetPayloadRaw
                
                ( (
                
                 char
                
                *)tlv_buf, len);
               
     
                
                 if
                
                (ret_val != NFC_RETVAL_OK)
               
     
                {
               
     
                
                 APP_ERROR_CHECK
                
                ((uint32_t) ret_val);
               
     
                }
               

     
     
     
3. Activate the NFC tag so that it starts sensing and reacts when an NFC field is detected:

   
            
             /* Start sensing NFC field. */
            
           
   
            ret_val =
            
             nfcStartEmulation
            
            ();
           
   
            
             if
            
            (ret_val != NFC_RETVAL_OK)
           
   
            {
           
   
            
             APP_ERROR_CHECK
            
            ((uint32_t) ret_val);
           
   
            }