Intermediate
30 min
0

Redefine control and security with versatile switch keylock solution based on SK14DG13 and PIC24FV16KA304

Maximizing security: How three-position sealed key locks redefine protection

Keylock Click with EasyPIC v8 for PIC24/dsPIC33

Published Nov 01, 2023

Click board™

Keylock Click

Development board

EasyPIC v8 for PIC24/dsPIC33

Compiler

NECTO Studio

MCU

PIC24FV16KA304

Explore the groundbreaking technology behind a key lock system that offers three distinct security levels

A

A

Hardware Overview

How does it work?

Keylock Click is based on the SK14DG13, a processed sealed key lock mechanism from NKK Switches that can be set in three different positions. The click is designed to run on either a 3.3V or 5V power supply. It communicates with the target microcontroller over the PWM, INT, and AN pin on the mikroBUS™ line. This Click board™

comes with two keys and a protective cap for the mechanism. The contact mechanism provides unequaled logic-level reliability and smoother, positive detent actuation. With its spring-operated steel ball, the detent mechanism gives crisp, positive action for accurate switch settings. 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.

Keylock Click top side image
Keylock Click bottom side image

Features overview

Development board

EasyPIC v8 for PIC24/dsPIC33 is a development board specially designed for the needs of rapid development of embedded applications. It supports a wide range of 16-bit PIC24/dsPIC33 microcontrollers from Microchip and has 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 for PIC24/dsPIC33 provides a fluid and immersive working experience, allowing access anywhere and under any circumstances. Each part of the EasyPIC

v8 for PIC24/dsPIC33 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 HOST/DEVICE, USB-UART, CAN, and LIN 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 16-bit PIC24/dsPIC33 MCUs, from the smallest PIC24/dsPIC33 MCUs with only 14 up to 28 pins. EasyPIC v8 for PIC24/dsPIC33 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 for PIC24/dsPIC33 horizontal image

Microcontroller Overview

MCU Card / MCU

default

Architecture

dsPIC

MCU Memory (KB)

16

Silicon Vendor

Microchip

Pin count

28

RAM (Bytes)

2048

Used MCU Pins

mikroBUS™ mapper

Keylock Position 1
RA0
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
Keylock Position 2
RB13
PWM
Keylock Position 3
RB7
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

Keylock Click Schematic schematic

Step by step

Project assembly

EasyPIC v8 for PIC24/dsPIC33 front image hardware assembly

Start by selecting your development board and Click board™. Begin with the EasyPIC v8 for PIC24/dsPIC33 as your development board.

EasyPIC v8 for PIC24/dsPIC33 front image hardware assembly
Buck 22 Click front image hardware assembly
MCU DIP 28 hardware assembly
EasyPIC PIC24/dsPIC33 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 Keylock Click driver.

Key functions:

  • keylock_check_pin - Checks pin state.

  • keylock_get_position - Gets key position.

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 Keylock Click example
 * 
 * # Description
 * This application monitors key position in its lock mechanism.
 *
 * The demo application is composed of two sections :
 * 
 * ## Application Init 
 * Initialization driver enables GPIO and also writes log.
 * 
 * ## Application Task  
 * Detects the position in which the key currently is.
 * Results are being sent to the Terminal, where you can track changes.
 * 
 * \author MikroE Team
 *
 */
// ------------------------------------------------------------------- INCLUDES

#include "board.h"
#include "log.h"
#include "keylock.h"

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

static keylock_t keylock;
static log_t logger;

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

void application_init ( void )
{
    log_cfg_t log_cfg;
    keylock_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.

    keylock_cfg_setup( &cfg );
    KEYLOCK_MAP_MIKROBUS( cfg, MIKROBUS_1 );
    keylock_init( &keylock, &cfg );
    Delay_ms( 100 );
    log_printf( &logger, "--------------- \r\n" );
    log_printf( &logger, " Keylock Click \r\n" );
    log_printf( &logger, "--------------- \r\n" );
}

void application_task ( void )
{
    uint8_t new_state;
    uint8_t old_state = 0;

    new_state = keylock_get_position( &keylock );

    if ( old_state != new_state )
    {
        if ( new_state == KEYLOCK_KEY_POS_1 )
        {
            log_printf( &logger, " Position ONE \r\n" );
        }
        else if ( new_state == KEYLOCK_KEY_POS_2 )
        {
            log_printf( &logger, " Position TWO \r\n" );
        }
        else if ( new_state == KEYLOCK_KEY_POS_3 )
        {
            log_printf( &logger, " Position THREE \r\n" );
        }
        else
        {
            log_printf( &logger, " ERROR!!! \r\n" );
        }
        
    old_state = new_state;
    log_printf( &logger, "---------------- \r\n" );
    }

    Delay_ms( 500 );
}

void main ( void )
{
    application_init( );

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

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

Additional Support

Resources