Beginner
10 min

Achieve precise and natural control using COM-09032 and STM32F407VGT6

Level up your HMI experience

THUMBSTICK Click with Clicker 4 for STM32F4

Published Dec 29, 2023

Click board™

THUMBSTICK Click

Development board

Clicker 4 for STM32F4

Compiler

NECTO Studio

MCU

STM32F407VGT6

Achieve precise analog control for gaming consoles and controllers, enhancing the gameplay experience, or applications that require accurate control inputs, such as robotics or drone navigation systems

A

A

Hardware Overview

How does it work?

Thumbstick Click is based on the COM-09032, a high-quality 2-axis analog-type thumbstick from Sparkfun. This type of thumbstick has a self-centering feature (spring return) that allows it to center itself the moment when you release it. It also contains a comfortable cup-type black knob/cap, which gives the feel of a thumbstick, making it very similar to the 'analog' joysticks used on joypads on popular gaming consoles like PSP joysticks. This feature makes it suitable for numerous applications as a human-machine interface. It comprises two 10kΩ potentiometers, one for up/down and another for left/right direction, used as dual adjustable voltage dividers providing 2-axis analog input in a control stick form. With the thumbstick fully

assembled and functioning, the voltage will follow the motion of the thumbstick as it is moved around. The measurements of the potentiometer resistance change are needed to read the thumbstick's physical position. That's why the MCP3204, a 12-bit A/D converter with conversion rates of up to 100ksps from Microchip, connects the thumbstick with mikroBUS™ using a simple serial interface compatible with the SPI protocol to determine the value of the joystick's X and Y. As the MCP3204 has a resolution of 12 bits, the values on each analog channel (axis) can vary from 0 to 4095. So, if the stick is moved on the X axis from one end to the other, the X values will change from 0 to 4095, and a similar thing happens when moved along the

Y axis. The value of the thumbstick staying in its center position is around 2048. Also, the thumbstick has a pushbutton feature that sends an interrupt signal to the host MCU through the INT line of the mikroBUS™ socket. This Click board™ can operate with both 3.3V and 5V logic voltage levels selected via SMD jumper. This way, it is allowed for both 3.3V and 5V capable MCUs to use the communication lines properly. However, the 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.

THUMBSTICK Click hardware overview image

Features overview

Development board

Clicker 4 for STM32F4 is a compact development board designed as a complete solution that you can use to quickly build your own gadgets with unique functionalities. Featuring an STM32F407VGT6 MCU, four mikroBUS™ sockets for Click boards™ connectivity, power management, and more, it represents a perfect solution for the rapid development of many different types of applications. At its core is an STM32F407VGT6 MCU, a powerful microcontroller by STMicroelectronics based on the high-performance

Arm® Cortex®-M4 32-bit processor core operating at up to 168 MHz frequency. It provides sufficient processing power for the most demanding tasks, allowing Clicker 4 to adapt to any specific application requirements. Besides two 1x20 pin headers, four improved mikroBUS™ sockets represent the most distinctive connectivity feature, allowing access to a huge base of Click boards™, growing on a daily basis. Each section of Clicker 4 is clearly marked, offering an intuitive and clean interface. This makes working with the

development board much simpler and, thus, faster. The usability of Clicker 4 doesn’t end with its ability to accelerate the prototyping and application development stages: it is designed as a complete solution that can be implemented directly into any project, with no additional hardware modifications required. Four mounting holes [4.2mm/0.165”] at all four corners allow simple installation by using mounting screws.

Clicker 4 for STM32F4 double image

Microcontroller Overview

MCU Card / MCU

default

Architecture

ARM Cortex-M4

MCU Memory (KB)

10

Silicon Vendor

STMicroelectronics

Pin count

100

RAM (Bytes)

100

Used MCU Pins

mikroBUS™ mapper

NC
NC
AN
NC
NC
RST
SPI Chip Select
PA4
CS
SPI Clock
PA5
SCK
SPI Data OUT
PA6
MISO
SPI Data IN
PA7
MOSI
Power Supply
3.3V
3.3V
Ground
GND
GND
NC
NC
PWM
Interrupt
PD0
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

Schematic

THUMBSTICK Click Schematic schematic

Step by step

Project assembly

Clicker 4 for STM32F4 front image hardware assembly

Start by selecting your development board and Click board™. Begin with the Clicker 4 for STM32F4 as your development board.

Clicker 4 for STM32F4 front image hardware assembly
Rotary O 2 Click front image hardware assembly
Clicker 4 STM32F4 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
Clicker 4 for STM32F4 HA 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

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 Thumbstick Click driver.

Key functions:

  • thumbstick_button_state - Get state of thumbstick button function

  • thumbstick_get_position - Get thumbstick position by axis 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 Thumbstick Click example
 * 
 * # Description
 * The demo application shows clickboard axis postioning and button pressed.
 *
 * The demo application is composed of two sections :
 * 
 * ## Application Init 
 * Initialization of click board's and log's objects.
 * 
 * ## Application Task  
 * It reads the position of the thumbstick,
 *  - You will get data on log on every change of thumbstick axis position, or if you hold 
 *      thumbstick in one postion it will repeat the same log when timer reaches timeout.
 *  - You will get data on log whenever you press thumbstick button and release it.
 * 
 * \author Luka Filipovic
 *
 */
// ------------------------------------------------------------------- INCLUDES

#include "board.h"
#include "log.h"
#include "thumbstick.h"

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

static thumbstick_t thumbstick;
static log_t logger;


static uint8_t old_butt_state;
static uint8_t button_state;

static thumbstick_position_t old_pos;
static thumbstick_position_t thumbstick_pos;

static uint16_t timer_cnt;
#define TIMER_FLAG 1000

static bool change_state;

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

void application_init ( void )
{
    log_cfg_t log_cfg;
    thumbstick_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.

    thumbstick_cfg_setup( &cfg );
    THUMBSTICK_MAP_MIKROBUS( cfg, MIKROBUS_1 );
    thumbstick_init( &thumbstick, &cfg );
    
    thumbstick_set_sensitivity( POSTION_SENS_DEFAULT );
    
    thumbstick_get_position( &thumbstick, &old_pos );
    old_butt_state = thumbstick_button_state( &thumbstick );
    timer_cnt = 0;
    change_state = false;
}

void application_task ( void )
{
    //Button pressed
    button_state = thumbstick_button_state( &thumbstick );

    if ( old_butt_state != button_state )
    {
        if ( button_state == THUMBSTICK_PRESS_BUTTON )
        {
            log_printf( &logger, ">> Button is pressed \r\n" );
            Delay_ms( 100 );
        }
        else
        {
            log_printf( &logger, ">> Button is released \r\n" );
            Delay_ms( 100 );
        }
        old_butt_state = button_state;
    }

    //Thumbstick postion
    thumbstick_get_position( &thumbstick, &thumbstick_pos );
    
    if ( ( old_pos.vertical != thumbstick_pos.vertical ) || ( timer_cnt >= TIMER_FLAG ) )
    {
        if ( thumbstick_pos.vertical == THUMBSTICK_POSITION_TOP )
        {
            log_printf( &logger, ">> TOP \r\n" );
            change_state = true;
        }
        else if ( thumbstick_pos.vertical == THUMBSTICK_POSITION_BOTTOM )
        {
            log_printf( &logger, ">> BOTTOM \r\n" );
            change_state = true;
        }
        
        old_pos = thumbstick_pos;
    }
    
    if ( (old_pos.horizontal != thumbstick_pos.horizontal ) || ( timer_cnt >= TIMER_FLAG )  )
    {
        if ( thumbstick_pos.horizontal == THUMBSTICK_POSITION_LEFT )
        {
            log_printf( &logger, ">> LEFT \r\n" );
            change_state = true;
        }
        else if ( thumbstick_pos.horizontal == THUMBSTICK_POSITION_RIGHT )
        {
            log_printf( &logger, ">> RIGHT \r\n" );
            change_state = true;
        }
        
        old_pos = thumbstick_pos;
    }
    
    if ( ( timer_cnt >= TIMER_FLAG ) || ( change_state == true )  )
    {
        timer_cnt = 0;
        change_state = false;
    }
    
    timer_cnt++;
    Delay_ms( 1 );
}

void main ( void )
{
    application_init( );

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


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

Additional Support

Resources