Beginner
10 min

Control things like volume or brightness and visually see those adjustments with TLC5925 and MK64FN1M0VDC12

Rotary knob with an illuminating ring that shows adjustment levels visually

Rotary R 2 Click with Clicker 2 for Kinetis

Published Feb 28, 2024

Click board™

Rotary R 2 Click

Dev Board

Clicker 2 for Kinetis

Compiler

NECTO Studio

MCU

MK64FN1M0VDC12

Ideal for precise user input, such as audio equipment (volume controls), lighting controls (intensity adjustment), or any application where a selection or setting needs to be adjusted accurately

A

A

Hardware Overview

How does it work?

Rotary R 2 Click is based on the TLC5925, a low-power 16-channel constant-current LED sink driver from Texas Instruments that, combined with a high-quality rotary encoder from ALPS, the EC12D1564402, allows you to add a precision input knob to your design. The EC12D1564402 incremental rotary encoder is surrounded by a ring of 16 red LEDs where a single rotation is divided into 15 discrete steps (in contrast to a potentiometer, a rotary encoder can be spun around continuously). The driver can control each LED individually, allowing various lighting effects to be programmed. The encoder outputs A and B signals (out of phase to each other) on the two mikroBUS™ lines, alongside the knob push-button

feature, which outputs through the interrupt line. The EC12D1564402 is a 15-pulse incremental rotary encoder with a push button. This encoder has unique mechanical specifications (debouncing time for its internal switches goes down to 2ms), and it can withstand a huge number of switching cycles, up to 30.000. The supporting debouncing circuitry allows contacts to settle before the output is triggered fully. Rotary R 2 Click uses a standard 4-wire SPI serial interface of the TLC5925 LED driver to communicate with the host MCU supporting clock frequency of up to 30MHz. Rotating the encoder, it outputs A and B signals (out of phase to each other) on the two mikroBUS™ lines, ENA and ENB pins of the

mikroBUS™ socket, alongside the push-button contact, which outputs through the SW pin (interrupt line) of the mikroBUS™ socket. Two SN74LVC1T45 single-bit bus transceivers from Texas Instruments are used for logic-level translation. This Click board™ can operate with either 3.3V or 5V logic voltage levels selected via the VCC 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.

Rotary R 2 Click hardware overview image

Features overview

Development board

Clicker 2 for Kinetis is a compact starter development board that brings the flexibility of add-on Click boards™ to your favorite microcontroller, making it a perfect starter kit for implementing your ideas. It comes with an onboard 32-bit ARM Cortex-M4F microcontroller, the MK64FN1M0VDC12 from NXP Semiconductors, two mikroBUS™ sockets for Click board™ connectivity, a USB connector, LED indicators, buttons, a JTAG programmer connector, and two 26-pin headers for interfacing with external electronics. Its compact design with clear and easily recognizable silkscreen markings allows you to build gadgets with unique functionalities and

features quickly. Each part of the Clicker 2 for Kinetis development kit contains the components necessary for the most efficient operation of the same board. In addition to the possibility of choosing the Clicker 2 for Kinetis programming method, using a USB HID mikroBootloader or an external mikroProg connector for Kinetis programmer, the Clicker 2 board also includes a clean and regulated power supply module for the development kit. It provides two ways of board-powering; through the USB Micro-B cable, where onboard voltage regulators provide the appropriate voltage levels to each component on the board, or

using a Li-Polymer battery via an onboard battery connector. All communication methods that mikroBUS™ itself supports are on this board, including the well-established mikroBUS™ socket, reset button, and several user-configurable buttons and LED indicators. Clicker 2 for Kinetis 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.

Clicker 2 for Kinetis dimensions image

Microcontroller Overview

MCU Card / MCU

default

Architecture

ARM Cortex-M4

MCU Memory (KB)

1024

Silicon Vendor

NXP

Pin count

121

RAM (Bytes)

262144

Used MCU Pins

mikroBUS™ mapper

Encoder Output B
PB2
AN
ID SEL
PB11
RST
SPI Select / ID COMM
PC4
CS
SPI Clock
PC5
SCK
SPI Data OUT
PC7
MISO
SPI Data IN
PC6
MOSI
Power Supply
3.3V
3.3V
Ground
GND
GND
Encoder Output A
PA10
PWM
Switch Output
PB13
INT
NC
NC
TX
NC
NC
RX
NC
NC
SCL
NC
NC
SDA
Power Supply
5V
5V
Ground
GND
GND
1

Take a closer look

Click board™ Schematic

Rotary R 2 Click Schematic schematic

Step by step

Project assembly

Clicker 2 for PIC32MZ front image hardware assembly

Start by selecting your development board and Click board™. Begin with the Clicker 2 for Kinetis as your development board.

Clicker 2 for PIC32MZ front image hardware assembly
GNSS2 Click front image hardware assembly
Prog-cut hardware assembly
GNSS2 Click complete accessories setup image hardware assembly
Micro B Connector Clicker 2 Access - 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
Flip&Click PIC32MZ MCU step 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

1. Application Output - In Debug mode, the 'Application Output' window enables real-time data monitoring, offering direct insight into execution results. Ensure proper data display by configuring the environment correctly using the provided tutorial.

2. UART Terminal - Use the UART Terminal to monitor data transmission via a USB to UART converter, allowing direct communication between the Click board™ and your development system. Configure the baud rate and other serial settings according to your project's requirements to ensure proper functionality. For step-by-step setup instructions, refer to the provided tutorial.

3. Plot Output - The Plot feature offers a powerful way to visualize real-time sensor data, enabling trend analysis, debugging, and comparison of multiple data points. To set it up correctly, follow the provided tutorial, which includes a step-by-step example of using the Plot feature to display Click board™ readings. To use the Plot feature in your code, use the function: plot(*insert_graph_name*, variable_name);. This is a general format, and it is up to the user to replace 'insert_graph_name' with the actual graph name and 'variable_name' with the parameter to be displayed.

Software Support

Library Description

This library contains API for Rotary R 2 Click driver.

Key functions:

  • rotaryr2_set_led_pos - This function turns on the LED for the selected LED position

  • rotaryr2_set_led_data - This function, using SPI serial interface, writes a desired 16-bit data

  • rotaryr2_get_state_switch - This function return rotary encoder switch signal, states of the SW(INT)

Open Source

Code example

The complete application code and a ready-to-use project are available through the NECTO Studio Package Manager for direct installation in the NECTO Studio. The application code can also be found on the MIKROE GitHub account.

/*!
 * @file main.c
 * @brief Rotary R 2 Click example
 *
 * # Description
 * This library contains the API for the Rotary R 2 Click driver 
 * to control LEDs states and a rotary encoder position readings.
 *
 * The demo application is composed of two sections :
 *
 * ## Application Init
 * Initialization of SPI module and log UART.
 * After the driver init, the app executes a default configuration and turn off all LEDs.
 *
 * ## Application Task
 * This example demonstrates the use of the Rotary R 2 Click board.
 * The demo example shows the functionality of a rotary encoder used to control LEDs.
 *
 * @author Nenad Filipovic
 *
 */

#include "board.h"
#include "log.h"
#include "rotaryr2.h"

#define ROTARYR2_ONE_LED          ROTARYR2_SET_LED_DATA_1
#define ROTARYR2_TWO_LED          ROTARYR2_SET_LED_DATA_1  | ROTARYR2_SET_LED_DATA_9
#define ROTARYR2_FOUR_LED         ROTARYR2_SET_LED_DATA_1  | ROTARYR2_SET_LED_DATA_5  | \
                                  ROTARYR2_SET_LED_DATA_9  | ROTARYR2_SET_LED_DATA_13 
#define ROTARYR2_EIGHT_LED        ROTARYR2_SET_LED_DATA_1  | ROTARYR2_SET_LED_DATA_3  | \
                                  ROTARYR2_SET_LED_DATA_5  | ROTARYR2_SET_LED_DATA_7  | \
                                  ROTARYR2_SET_LED_DATA_9  | ROTARYR2_SET_LED_DATA_11 | \
                                  ROTARYR2_SET_LED_DATA_13 | ROTARYR2_SET_LED_DATA_15
#define ROTARYR2_EIGHT_LED_INV    ROTARYR2_SET_LED_DATA_2  | ROTARYR2_SET_LED_DATA_4  | \
                                  ROTARYR2_SET_LED_DATA_6  | ROTARYR2_SET_LED_DATA_8  | \
                                  ROTARYR2_SET_LED_DATA_10 | ROTARYR2_SET_LED_DATA_12 | \
                                  ROTARYR2_SET_LED_DATA_14 | ROTARYR2_SET_LED_DATA_16

static rotaryr2_t rotaryr2;
static log_t logger;

static uint8_t start_rot_status = 0;
static uint8_t led_demo_state = 0;
static uint8_t old_state = 0;
static uint8_t new_state = 1;
static uint8_t old_rot_state = 0;
static uint8_t new_rot_state = 1;
static uint16_t led_data = 1;

/**
 * @brief Rotary R 2 select LED demo data function.
 * @details This function selects one of the four LED demo data 
 * based on the current state of the LED demo.
 * @return LED demo data:
 *         @li @c 0x0001 (ROTARYR2_ONE_LED)   - Turn ON LED[1],
 *         @li @c 0x0101 (ROTARYR2_TWO_LED)   - Turn ON LED[1,9],
 *         @li @c 0x0101 (ROTARYR2_FOUR_LED)  - Turn ON LED[1,5,9,13],
 *         @li @c 0x5555 (ROTARYR2_EIGHT_LED) - Turn ON LED[1,3,5,7,9,11,13,15].
 */
static uint16_t rotaryr2_sel_led_demo_data ( uint8_t led_demo_state );

/**
 * @brief Rotary R 2 switch detection function.
 * @details This function is used for the switch state detection.
 * @return Nothing.
 */
static void rotaryr2_switch_detection ( void );

/**
 * @brief Rotary R 2 encoder mechanism function.
 * @details This function is used to control the state of the LEDs 
 * by detecting the rotation direction of the rotary encoder.
 * @return Nothing.
 */
static void rotaryr2_encoder_mechanism ( void );

void application_init ( void )
{
    log_cfg_t log_cfg;  /**< Logger config object. */
    rotaryr2_cfg_t rotaryr2_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.
    rotaryr2_cfg_setup( &rotaryr2_cfg );
    ROTARYR2_MAP_MIKROBUS( rotaryr2_cfg, MIKROBUS_1 );
    if ( SPI_MASTER_ERROR == rotaryr2_init( &rotaryr2, &rotaryr2_cfg ) )
    {
        log_error( &logger, " Communication init." );
        for ( ; ; );
    }
    
    if ( ROTARYR2_ERROR == rotaryr2_default_cfg ( &rotaryr2 ) )
    {
        log_error( &logger, " Default configuration." );
        for ( ; ; );
    }
    
    log_info( &logger, " Application Task " );
}

void application_task ( void )
{
    if ( ROTARYR2_OK == rotaryr2_set_led_data( &rotaryr2, led_data ) )
    {
        rotaryr2_switch_detection( );
        rotaryr2_encoder_mechanism( );
    }
}

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

    return 0;
}

static uint16_t rotaryr2_sel_led_demo_data ( uint8_t led_demo_state ) 
{
    switch ( led_demo_state ) 
    {
        case 0: 
        {
            return ROTARYR2_ONE_LED;
            break;
        }
        case 1: 
        {
            return ROTARYR2_TWO_LED;
            break;
        }
        case 2: 
        {
            return ROTARYR2_FOUR_LED;
            break;
        }
        case 3: 
        {
            return ROTARYR2_EIGHT_LED;
            break;
        }
        default: 
        {
            return ROTARYR2_ONE_LED;
            break;
        }
    }
}

static void rotaryr2_switch_detection ( void )
{
    if ( rotaryr2_get_state_switch( &rotaryr2 ) ) 
    {
        new_state = 1;
        if ( (  1 == new_state ) && ( 0 == old_state ) ) 
        {
            old_state = 1;
            led_demo_state = ( led_demo_state + 1 ) % 5;
            if ( 4 == led_demo_state ) 
            {
                for ( uint8_t n_cnt = 0; n_cnt < 10; n_cnt++ )
                {
                    rotaryr2_set_led_data( &rotaryr2, ROTARYR2_EIGHT_LED_INV );
                    Delay_ms( 100 );
                    rotaryr2_set_led_data( &rotaryr2, ROTARYR2_EIGHT_LED );
                    Delay_ms( 100 );
                }
                
                for ( uint8_t led_p = ROTARYR2_SET_LED_POS_1; led_p <= ROTARYR2_SET_LED_POS_16; led_p++ ) 
                {
                    rotaryr2_set_led_pos( &rotaryr2, led_p );
                    Delay_ms( 100 );
                }
                
                led_demo_state = 0;
                led_data = rotaryr2_sel_led_demo_data( led_demo_state );
            }
            else 
            {
                led_data = rotaryr2_sel_led_demo_data( led_demo_state );
            }
        }
    }
    else 
    {
        old_state = 0;
    }
}

static void rotaryr2_encoder_mechanism ( void )
{
    if ( rotaryr2_get_state_ena( &rotaryr2 ) == rotaryr2_get_state_enb( &rotaryr2 ) ) 
    {
        old_rot_state = 0;
        start_rot_status = rotaryr2_get_state_ena( &rotaryr2 ) && rotaryr2_get_state_enb( &rotaryr2 );
    }
    else 
    {
        new_rot_state = 1;
        if ( new_rot_state != old_rot_state ) 
        {
            old_rot_state = 1;
            if ( start_rot_status != rotaryr2_get_state_ena( &rotaryr2 ) ) 
            {
                led_data = ( led_data << 1 ) | ( led_data >> 15 );
            }
            else 
            {
                led_data = ( led_data >> 1 ) | ( led_data << 15 );
            }
        }
    }
}

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

Additional Support

Resources

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