Intermediate
30 min

Transform device-to-cloud communication with NTP5332 and PIC18F45K42

NFC forum-compliant I2C bridge

NTAG 5 Link Click with EasyPIC v8

Published May 31, 2023

Click board™

NTAG 5 Link Click

Dev Board

EasyPIC v8

Compiler

NECTO Studio

MCU

PIC18F45K42

Experience the future-proof security with thishighly integrated NFC solution, forging a standard-based link from device to cloud

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Hardware Overview

How does it work?

NTAG 5 Link Click is based on the NTP5332, a highly integrated NFC IC optimized for sensor-driven applications that act as a bridge between an NFC-enabled device and any I2C slave from NXP Semiconductors. This highly integrated NFC IC creates a secure, standard-based link from the device to the cloud in a future-proof way to address and even power sensors. Operating at 13.56 MHz, the NTP5332 is an NFC Forum Type 5 Tag, which can be read and written by an NFC-enabled device at close range and an ISO/IEC 15693-enabled industrial reader over a more extended range (>60cm). With NTAG 5 Link, the device can connect to the cloud with a single tap. The connection uses an NFC Forum-compliant data exchange mechanism involving SRAM to ensure interoperable data transfers. Also, it offers 2048 bytes of memory divided into three areas where each area can use a different protection level, varying from no protection to 32-/64-bit password-protected read/write access or up to 128-bit-AES mutual authentication protected read/write access. The NTAG 5 Link comes with pre-programmed proof-of-origin functionality to verify

authenticity. The ECC-based originality signature can be reprogrammed or locked by the customer through its registers. This Click board™ communicates with MCU using the standard I2C 2-Wire interface to read data and configure settings, supporting Standard Mode operation with a clock frequency of 100kHz and Fast Mode up to 400kHz. The NTP5332 also offers a transparent I2C master mode, for example, to read sensors without a microcontroller. The RF interface initiates an I2C Master communication, which can trigger a read or write transaction to an external I2C slave. Alongside this feature, an integrated SRAM is used as intermediate data storage. Session registers reflect the status of the I2C Master transaction. Therefore an RF reader has to poll for the status bits related to I2C Master to know the status of the current I2C transaction. The NTAG 5 Link can also operate as a standalone solution by drawing power from the NFC field of an NFC device. It supports an energy harvesting feature, activated by an onboard switch marked as HARVEST, which means it can supply power to other components in the system, in this case,

to supply the NTP5332. NTAG 5 Link can provide a fixed configurable voltage level of 1.8V, 2.4V, or 3V, selectable through register configuration when sufficient energy is available. In addition, this Click board™ can be placed in a hard power-down mode by setting the HPD pin routed on the RST pin of the mikroBUS™ socket. Besides, it also has an event detection and field detection functionality that defines the ED pin's behavior routed on the INT pin of the mikroBUS™ socket. This pin's behavior depends on various events such as the presence/absence of the NFC field, arbiter locked/unlocked EEPROM to NFC interface, Write/Read command ongoing, and more. This Click board™ can only be operated with a 3.3V logic voltage level. The board must perform appropriate logic voltage level conversion before using MCUs with different logic levels. However, the Click board™ comes equipped with a library containing functions and an example code that can be used as a reference for further development.

NTAG 5 Link Click top side image
NTAG 5 Link Click lateral side image
NTAG 5 Link Click bottom side image

Features overview

Development board

EasyPIC v8 is a development board specially designed for the needs of rapid development of embedded applications. It supports many high pin count 8-bit PIC microcontrollers from Microchip, regardless of their number of pins, and a broad set of unique functions, such as the first-ever embedded debugger/programmer. The development board is well organized and designed so that the end-user has all the necessary elements, such as switches, buttons, indicators, connectors, and others, in one place. Thanks to innovative manufacturing technology, EasyPIC v8 provides a fluid and immersive working experience, allowing access anywhere and under any

circumstances at any time. Each part of the EasyPIC v8 development board contains the components necessary for the most efficient operation of the same board. In addition to the advanced integrated CODEGRIP programmer/debugger module, which offers many valuable programming/debugging options and seamless integration with the Mikroe software environment, the board also includes a clean and regulated power supply module for the development board. It can use a wide range of external power sources, including a battery, an external 12V power supply, and a power source via the USB Type-C (USB-C) connector.

Communication options such as USB-UART, USB DEVICE, and CAN are also included, including the well-established mikroBUS™ standard, two display options (graphical and character-based LCD), and several different DIP sockets. These sockets cover a wide range of 8-bit PIC MCUs, from the smallest PIC MCU devices with only eight up to forty pins. EasyPIC v8 is an integral part of the Mikroe ecosystem for rapid development. Natively supported by Mikroe software tools, it covers many aspects of prototyping and development thanks to a considerable number of different Click boards™ (over a thousand boards), the number of which is growing every day.

EasyPIC v8 horizontal image

Microcontroller Overview

MCU Card / MCU

PIC18F45K42

Architecture

PIC

MCU Memory (KB)

32

Silicon Vendor

Microchip

Pin count

40

RAM (Bytes)

2048

Used MCU Pins

mikroBUS™ mapper

NC
NC
AN
Hard Power Down
RE1
RST
NC
NC
CS
NC
NC
SCK
NC
NC
MISO
NC
NC
MOSI
Power Supply
3.3V
3.3V
Ground
GND
GND
NC
NC
PWM
Event Detection
RB0
INT
NC
NC
TX
NC
NC
RX
I2C Clock
RC3
SCL
I2C Data
RC4
SDA
NC
NC
5V
Ground
GND
GND
1

Take a closer look

Schematic

NTAG 5 Link Click Schematic schematic

Step by step

Project assembly

EasyPIC v8 front image hardware assembly

Start by selecting your development board and Click board™. Begin with the EasyPIC v8 as your development board.

EasyPIC v8 front image hardware assembly
Buck 22 Click front image hardware assembly
MCU DIP 40 hardware assembly
EasyPIC v8 DIP MB 1 - upright/background hardware assembly
Necto image step 2 hardware assembly
Necto image step 3 hardware assembly
Necto image step 4 hardware assembly
NECTO Compiler Selection Step Image hardware assembly
NECTO Output Selection Step Image hardware assembly
Necto image step 6 hardware assembly
Necto DIP image step 7 hardware assembly
Necto image step 8 hardware assembly
Necto image step 9 hardware assembly
Necto image step 10 hardware assembly
Necto PreFlash Image hardware assembly

Track your results in real time

Application Output

After pressing the "FLASH" button on the left-side panel, it is necessary to open the UART terminal to display the achieved results. By clicking on the Tools icon in the right-hand panel, multiple different functions are displayed, among which is the UART Terminal. Click on the offered "UART Terminal" icon.

UART Application Output Step 1

Once the UART terminal is opened, the window takes on a new form. At the top of the tab are two buttons, one for adjusting the parameters of the UART terminal and the other for connecting the UART terminal. The tab's lower part is reserved for displaying the achieved results. Before connecting, the terminal has a Disconnected status, indicating that the terminal is not yet active. Before connecting, it is necessary to check the set parameters of the UART terminal. Click on the "OPTIONS" button.

UART Application Output Step 2

In the newly opened UART Terminal Options field, we check if the terminal settings are correct, such as the set port and the Baud rate of UART communication. If the data is not displayed properly, it is possible that the Baud rate value is not set correctly and needs to be adjusted to 115200. If all the parameters are set correctly, click on "CONFIGURE".

UART Application Output Step 3

The next step is to click on the "CONNECT" button, after which the terminal status changes from Disconnected to Connected in green, and the data is displayed in the Received data field.

UART Application Output Step 4

Software Support

Library Description

This library contains API for NTAG 5 Link Click driver.

Key functions:

  • ntag5link_write_ndef_uri_record This function writes specific NDEF URI record to the memory address specified with NTAG5LINK_NDEF_MESSAGE_START_ADDRESS macro.

  • ntag5link_write_message_to_memory This function writes a specified number of data bytes to the user memory starting from block_addr.

  • ntag5link_read_message_from_memory This function reads a specified number of data bytes from the user memory starting from @b block_addr.

Open Source

Code example

This example can be found in NECTO Studio. Feel free to download the code, or you can copy the code below.

/*!
 * @file main.c
 * @brief NTAG5Link Click example
 *
 * # Description
 * This example demonstrates the use of NTAG 5 Link click board by programming the
 * specified NDEF URI record to the memory, and showing the memory read/write feature.
 *
 * The demo application is composed of two sections :
 *
 * ## Application Init
 * Initializes the driver and logger and performs the click default configuration which 
 * enables the device and formats its user memory. After that it programs the specified 
 * NDEF URI record to the memory.
 *
 * ## Application Task
 * Writes a desired number of data bytes to the memory and verifies that it is written 
 * correctly by reading from the same memory location and displaying the memory content 
 * on the USB UART approximately every 5 seconds.
 *
 * @author Stefan Filipovic
 *
 */

#include "board.h"
#include "log.h"
#include "ntag5link.h"

/**
 * URL to store to memory as NDEF URI record
 */
#define URI_DATA                "www.mikroe.com/ntag-5-link-click" 

/**
 * Starting block address to where the text message will be stored
 * Must be > ( NTAG5LINK_NDEF_MESSAGE_START_ADDRESS + sizeof ( URI_DATA ) / NTAG5LINK_MEMORY_BLOCK_SIZE + 3 )
 * to avoid overwriting NDEF URI record.
 */
#define TEXT_MESSAGE_ADDRESS    0x0040

/**
 * Text message content that will be stored to memory
 */
#define TEXT_MESSAGE            "MikroE - NTAG 5 Link click"

static ntag5link_t ntag5link;
static log_t logger;

void application_init ( void ) 
{
    log_cfg_t log_cfg;  /**< Logger config object. */
    ntag5link_cfg_t ntag5link_cfg;  /**< Click config object. */

    /** 
     * Logger initialization.
     * Default baud rate: 115200
     * Default log level: LOG_LEVEL_DEBUG
     * @note If USB_UART_RX and USB_UART_TX 
     * are defined as HAL_PIN_NC, you will 
     * need to define them manually for log to work. 
     * See @b LOG_MAP_USB_UART macro definition for detailed explanation.
     */
    LOG_MAP_USB_UART( log_cfg );
    log_init( &logger, &log_cfg );
    log_info( &logger, " Application Init " );

    // Click initialization.
    ntag5link_cfg_setup( &ntag5link_cfg );
    NTAG5LINK_MAP_MIKROBUS( ntag5link_cfg, MIKROBUS_1 );
    if ( I2C_MASTER_ERROR == ntag5link_init( &ntag5link, &ntag5link_cfg ) ) 
    {
        log_error( &logger, " Communication init." );
        for ( ; ; );
    }
    
    if ( NTAG5LINK_ERROR == ntag5link_default_cfg ( &ntag5link ) )
    {
        log_error( &logger, " Default configuration." );
        for ( ; ; );
    }
    
    if ( NTAG5LINK_OK == ntag5link_write_ndef_uri_record ( &ntag5link, NTAG5LINK_URI_PREFIX_4, 
                                                           URI_DATA, strlen ( URI_DATA ) ) )
    {
        log_printf( &logger, " NDEF URI record \"https://%s\" has been written\r\n", ( char * ) URI_DATA );
    }
    
    log_info( &logger, " Application Task " );
}

void application_task ( void ) 
{
    uint8_t message_buf[ 100 ] = { 0 };
    if ( NTAG5LINK_OK == ntag5link_write_message_to_memory ( &ntag5link, 
                                                             TEXT_MESSAGE_ADDRESS, 
                                                             TEXT_MESSAGE, 
                                                             strlen ( TEXT_MESSAGE ) ) )
    {
        log_printf( &logger, " \"%s\" has been written to memory address 0x%.4X \r\n", 
                    ( char * ) TEXT_MESSAGE, ( uint16_t ) TEXT_MESSAGE_ADDRESS );
    }
    if ( NTAG5LINK_OK == ntag5link_read_message_from_memory ( &ntag5link, 
                                                              TEXT_MESSAGE_ADDRESS, 
                                                              message_buf, 
                                                              strlen ( TEXT_MESSAGE ) ) )
    {
        log_printf( &logger, " \"%s\" has been read from memory address 0x%.4X \r\n\n", 
                    message_buf, ( uint16_t ) TEXT_MESSAGE_ADDRESS );
    }
    Delay_ms ( 5000 );
}

void main ( void ) 
{
    application_init( );

    for ( ; ; ) 
    {
        application_task( );
    }
}

// ------------------------------------------------------------------------ END

Additional Support

Resources