10 min

Experience the future of IR data exchange with TFDU4101, MCP2120 and STM32F446ZE

Send and receive Infrared (IR) serial data

IrDA2 Click with Fusion for STM32 v8

Published Jun 18, 2023

Click board™

IrDA2 Click

Development board

Fusion for STM32 v8


NECTO Studio



Achieve fast and stable infrared data communication, covering a more than 1m range and speeds up to 115.2 kbit/s



Hardware Overview

How does it work?

IrDA 2 Click is based on the MCP2120, a high-performance fully-static infrared encoder/decoder from Microchip for sending and receiving IR serial data from the infrared transceiver module, the TFDU4101 from Vishay semiconductor. This way, the MCP2120 adds IR capability to any embedded application with serial data. The data from a standard UART is encoded (modulated) and output as electrical pulses to the IR Transceiver. Besides, the IR Transceiver also receives and outputs electrical pulses, which the MCP2120 decodes (demodulates) and transmits by the UART interface. The latest IrDAR physical layer standard performs this modulation and demodulation method for fast infrared data communication, supporting IrDA speeds up to 115.2kbit/s. Integrated within the TFDU4101 transceiver module is a photo pin diode, an infrared emitter (IRED), and a low-power control

IC to provide a total front-end solution in a single package. This Click board™ covers the full IrDA range of more than 1m and can be turned on or off through the EN pin routed to the CS pin of the mikroBUS™ socket; hence, offering a switch operation to turn ON/OFF power delivery to the MCP2120. The MCP2120 will encode and decode serial data at the selected data or baud rate. The selection can be made by positioning SMD jumpers labeled as BR SEL in an appropriate position marked as 1 or 0. Also, the software baud rate selection is selected if all these jumpers are in a high (1) position. For any other inputs, the hardware select mode is active. This setting is latched when the MCP2120 is reset from the RST pin of the mikroBUS™ socket. After an MCP2120 reset, changing the value of the baud pins does not affect the device’s baud rate. Software baud data

rate is intended for use with systems where switching data rates must be performed frequently between the MCP2120 and the embedded host. In software baud mode, the MCP2120 differentiates between data and commands. This feature is controlled via the MOD pin routed to the AN pin of the mikroBUS™ socket. The MOD pin is used to switch between command and data modes, and when the MOD pin is in a low state, the MCP2120 is in command mode; otherwise, the MCP2120 is in data mode. This Click board™ can operate with either 3.3V or 5V logic voltage levels selected via the PWR SEL jumper. This way, both 3.3V and 5V capable MCUs can use the communication lines properly. Also, this Click board™ comes equipped with a library containing easy-to-use functions and an example code that can be used as a reference for further development.

IrDA2 Click hardware overview image

Features overview

Development board

Fusion for STM32 v8 is a development board specially designed for the needs of rapid development of embedded applications. It supports a wide range of microcontrollers, such as different 32-bit ARM® Cortex®-M based MCUs from STMicroelectronics, regardless of their number of pins, and a broad set of unique functions, such as the first-ever embedded debugger/programmer over WiFi. 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, Fusion for STM32 v8 provides a fluid and immersive working experience, allowing

access anywhere and under any circumstances at any time. Each part of the Fusion for STM32 v8 development board contains the components necessary for the most efficient operation of the same board. An advanced integrated CODEGRIP programmer/debugger module offers many valuable programming/debugging options, including support for JTAG, SWD, and SWO Trace (Single Wire Output)), and seamless integration with the Mikroe software environment. Besides, it 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 HOST/DEVICE, CAN (on the MCU card, if supported), and Ethernet is also included. In addition, it also has the well-established mikroBUS™ standard, a standardized socket for the MCU card (SiBRAIN standard), and two display options for the TFT board line of products and character-based LCD. Fusion for STM32 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.

Fusion for STM32 v8 horizontal image

Microcontroller Overview

MCU Card / MCU



8th Generation


ARM Cortex-M4

MCU Memory (KB)


Silicon Vendor


Pin count


RAM (Bytes)


Used MCU Pins

mikroBUS™ mapper

Mode Selection
Power Supply
Power Supply

Take a closer look


IrDA2 Click Schematic schematic

Step by step

Project assembly

Fusion for PIC v8 front image hardware assembly

Start by selecting your development board and Click board™. Begin with the Fusion for STM32 v8 as your development board.

Fusion for PIC v8 front image hardware assembly
Buck 22 Click front image hardware assembly
SiBRAIN for PIC32MZ1024EFK144 front image hardware assembly
v8 SiBRAIN 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 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 IrDA 2 Click driver.

Key functions:

  • irda2_generic_write - This function writes a desired number of data bytes by using UART serial interface

  • irda2_generic_read - This function reads a desired number of data bytes by using UART serial interface

  • irda2_reset - This function executes a device reset operation

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 IrDA 2 Click Example.
 * # Description
 * This example demonstrates the use of an IrDA 2 click board by showing
 * the communication between the two click boards.
 * The demo application is composed of two sections :
 * ## Application Init 
 * Initalizes device and makes an initial log.
 * ## Application Task
 * Depending on the selected application mode, it reads all the received data or 
 * sends the desired text message once per second.
 * @author MikroE Team
#include "board.h"
#include "log.h"
#include "irda2.h"

// Comment out the line below in order to switch the application mode to receiver

// Text message to send in the transmitter application mode
#define DEMO_TEXT_MESSAGE           "MIKROE - IrDA 2 click board\r\n\0"

static irda2_t irda2;
static log_t logger;

void application_init ( void ) 
    irda2_cfg_t irda2_cfg;
    log_cfg_t logger_cfg;

     * 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( logger_cfg );
    log_init( &logger, &logger_cfg );
    log_info( &logger, " Application Init " );
    //  Click initialization.
    irda2_cfg_setup( &irda2_cfg );
    IRDA2_MAP_MIKROBUS( irda2_cfg, MIKROBUS_1 );
    if ( UART_ERROR == irda2_init( &irda2, &irda2_cfg ) ) 
        log_error( &logger, " Communication init." );
        for ( ; ; );
    irda2_default_cfg( &irda2 );
    irda2_reset( &irda2 );

    log_printf( &logger, " Application Mode: Transmitter\r\n" );
    log_printf( &logger, " Application Mode: Receiver\r\n" );
    log_info( &logger, " Application Task " );

void application_task ( void ) 
    irda2_generic_write( &irda2, DEMO_TEXT_MESSAGE, strlen( DEMO_TEXT_MESSAGE ) );
    log_printf( &logger, "%s", ( char * ) DEMO_TEXT_MESSAGE );
    Delay_ms( 1000 ); 
    uint8_t rx_byte = 0;
    if ( 1 == irda2_generic_read( &irda2, &rx_byte, 1 ) )
       log_printf( &logger, "%c", rx_byte );

int main ( void ) 
    application_init( );
    for ( ; ; ) 
        application_task( );

    return 0;

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

Additional Support