Beginner
10 min

Integrate fiber-optic communication using IF-D91, IF-E97 and STM32L041C6 for lightning-speed data exchange

Transforming designs with fiber-optic innovation

Fiber Opt click with UNI Clicker

Published Aug 25, 2023

Click board™

Fiber Opt click

Dev Board

UNI Clicker

Compiler

NECTO Studio

MCU

STM32L041C6

Integrate high-speed fiber-optic communication and establish reliable, secure networks to meet growing demands for rapid data exchange while enhancing overall performance and efficiency.

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Hardware Overview

How does it work?

Fiber Opt Click is based on one IF-D91, a fiber-optic photodiode, and one IF-E97, a fiber-optic LED, both from Industrial Fiber Optics. The IF-D91 is a high-speed photodiode detector housed in a connector-less plastic fiber optic package. Its optical response extends from 400 to 1100nm, making it compatible with a wide range of visible and near-infrared LED and laser diode sources. The detector package features an internal micro-lens and a precision-molded PBT housing to ensure efficient optical coupling with standard 1000μm core 2.2mm jacketed plastic fiber cable capable of 100Mbps data rates. The IF-D91 can also be used for analog video links with bandwidths

up to 70MHz. The other precision-molded PBT housing with internal micro-lens, the IF-E97, is a high-optical-output visible red LED. The housing ensures efficient optical coupling with the same standard jacketed plastic fiber cable. The output spectrum is produced by a GaAlAs die, which peaks at 650nm, representing an optimal transmission window for PMMA plastic optical fiber. The visible red light has low attenuation in PMMA plastic fiber, aids troubleshooting installations, and is the main reason the IF-E97 achieves data rates of 1Mbps. This Click board™ communicates with the host MCU over selectable pins of the mikroBUS™ socket. Transmission can

be selected through the TX SEL selection jumper between the UART TX pin or PWM pin of the mikroBUS™ socket, as UART is selected by default. Received data is available on the RX pin of the mikroBUS™ socket. 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.

Fiber Opt Click hardware overview image

Features overview

Development board

UNI Clicker is a compact development board designed as a complete solution that brings the flexibility of add-on Click boards™ to your favorite microcontroller, making it a perfect starter kit for implementing your ideas. It supports a wide range of microcontrollers, such as different ARM, PIC32, dsPIC, PIC, and AVR from various vendors like Microchip, ST, NXP, and TI (regardless of their number of pins), four mikroBUS™ sockets for Click board™ connectivity, a USB connector, LED indicators, buttons, a debugger/programmer connector, and two 26-pin headers for interfacing with external electronics. Thanks to innovative manufacturing technology, it allows you to build

gadgets with unique functionalities and features quickly. Each part of the UNI Clicker development kit contains the components necessary for the most efficient operation of the same board. In addition to the possibility of choosing the UNI Clicker programming method, using a third-party programmer or CODEGRIP/mikroProg connected to onboard JTAG/SWD header, the UNI Clicker board also includes a clean and regulated power supply module for the development kit. It provides two ways of board-powering; through the USB Type-C (USB-C) connector, where onboard voltage regulators provide the appropriate voltage levels to each component on the board, or using a Li-Po/Li

Ion battery via an onboard battery connector. All communication methods that mikroBUS™ itself supports are on this board (plus USB HOST/DEVICE), including the well-established mikroBUS™ socket, a standardized socket for the MCU card (SiBRAIN standard), and several user-configurable buttons and LED indicators. UNI Clicker is an integral part of the Mikroe ecosystem, allowing you to create a new application in minutes. Natively supported by Mikroe software tools, it covers many aspects of prototyping thanks to a considerable number of different Click boards™ (over a thousand boards), the number of which is growing every day.

UNI clicker double image

Microcontroller Overview

MCU Card / MCU

default

Type

8th Generation

Architecture

ARM Cortex-M0

MCU Memory (KB)

32

Silicon Vendor

STMicroelectronics

Pin count

48

RAM (Bytes)

8192

Used MCU Pins

mikroBUS™ mapper

NC
NC
AN
NC
NC
RST
NC
NC
CS
NC
NC
SCK
NC
NC
MISO
NC
NC
MOSI
Power Supply
3.3V
3.3V
Ground
GND
GND
GPIO TX
PB13
PWM
NC
NC
INT
UART TX
PB10
TX
UART RX
PB11
RX
NC
NC
SCL
NC
NC
SDA
Power Supply
5V
5V
Ground
GND
GND
1

Take a closer look

Schematic

Fiber Opt click Schematic schematic

Step by step

Project assembly

UNI Clicker front image hardware assembly

Start by selecting your development board and Click board™. Begin with the UNI Clicker as your development board.

UNI Clicker front image hardware assembly
GNSS2 Click front image hardware assembly
SiBRAIN for STM32F745VG front image hardware assembly
Prog-cut hardware assembly
GNSS2 Click complete accessories setup image hardware assembly
UNI Clicker Access 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 image step 5 hardware assembly
Necto image step 6 hardware assembly
Necto image step 7 hardware assembly
Necto No Display image step 8 hardware assembly
Necto image step 9 hardware assembly
Necto image step 10 hardware assembly
Debug Image Necto Step hardware assembly

Track your results in real time

Application Output

After loading the code example, pressing the "DEBUG" button builds and programs it on the selected setup.

Application Output Step 1

After programming is completed, a header with buttons for various actions available in the IDE appears. By clicking the green "PLAY "button, we start reading the results achieved with Click board™.

Application Output Step 3

Upon completion of programming, the Application Output tab is automatically opened, where the achieved result can be read. In case of an inability to perform the Debug function, check if a proper connection between the MCU used by the setup and the CODEGRIP programmer has been established. A detailed explanation of the CODEGRIP-board connection can be found in the CODEGRIP User Manual. Please find it in the RESOURCES section.

Application Output Step 4

Software Support

Library Description

This library contains API for Fiber Opt Click driver.

Key functions:

  • fiberopt_generic_write - Generic single write function

  • fiberopt_generic_read - Generic single read function.

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 
 * \brief FiberOpt Click example
 * 
 * # Description
 * This application is an add-on for fiber-optical communication.
 *
 * The demo application is composed of two sections :
 * 
 * ## Application Init 
 * Initalizes UART driver and makes an initial log.
 * 
 * ## Application Task  
 * Example can either check if new data byte is received in rx buffer (ready for reading),
 * if ready than reads one byte from rx buffer and displays on USART terminal, or transmit message every 2 seconds.
 * 
 * \author MikroE Team
 *
 */
// ------------------------------------------------------------------- INCLUDES

#include "board.h"
#include "log.h"
#include "fiberopt.h"

// ------------------------------------------------------------------ VARIABLES

#define DEMO_APP_RECEIVER
//#define DEMO_APP_TRANSMITER

static fiberopt_t fiberopt;
static log_t logger;

static char demo_message[ 9 ] = { 'M', 'i', 'k', 'r', 'o', 'E', 13, 10, 0 };

// ------------------------------------------------------ APPLICATION FUNCTIONS

void application_init ( void )
{
    log_cfg_t log_cfg;
    fiberopt_cfg_t 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( log_cfg );
    log_init( &logger, &log_cfg );
    log_info( &logger, "---- Application Init ----" );

    //  Click initialization.

    fiberopt_cfg_setup( &cfg );
    FIBEROPT_MAP_MIKROBUS( cfg, MIKROBUS_1 );
    fiberopt_init( &fiberopt, &cfg );

    log_printf( &logger, "Initialized \r\n" );
    Delay_ms( 100 );
}

void application_task ( void )
{
    char tmp;
    
    //  Task implementation.
    
#ifdef DEMO_APP_RECEIVER

       // RECEIVER - UART polling

       tmp =  fiberopt_generic_single_read( &fiberopt );
       log_printf( &logger, "%c" , &tmp );
#endif
#ifdef DEMO_APP_TRANSMITER

       // TRANSMITER - TX each 2 sec
       
       fiberopt_generic_multi_write( &fiberopt, demo_message, 9 );
       Delay_ms( 2000 );
#endif
}

void main ( void )
{
    application_init( );

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


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

Additional Support

Resources