Intermediate
30 min
0

Experience motion like never before with MIS2DH and PIC18LF46K40

Move beyond simple tilting

Accel 21 Click with EasyPIC v8

Published Sep 12, 2023

Click board™

Accel 21 Click

Development board

EasyPIC v8

Compiler

NECTO Studio

MCU

PIC18LF46K40

Our three-axis accelerometer marvels at the intricate world of gravity and motion, providing unparalleled insights into three-dimensional movement.

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Hardware Overview

How does it work?

Accel 21 Click is based on the MIS2DH, a highly reliable digital triaxial acceleration and temperature sensor from STMicroelectronics. The MIS2DH is highly configurable with a programmable acceleration range of ±2g, ±4g, ±8g, or ±16g, capable of measuring accelerations with output data rates from 1Hz to 5.3kHz. Multiple operating modes (high-resolution, normal, and low-power mode) with various bandwidths and output data resolutions contribute significantly to applications such as activity monitoring and posture detection. The complete measurement chain is composed of a low-noise capacitive amplifier, which converts the capacitive

unbalance of the MEMS sensor into an analog voltage that will be available to the user through an analog-to-digital converter. The acceleration data is accessed through the I2C or SPI interface with a maximum frequency of 400kHz for I2C and 10MHz for SPI communication. The selection is made by positioning SMD jumpers labeled COMM SEL in an appropriate position. Note that all the jumpers' positions must be on the same side, or the Click board™ may become unresponsive. While the I2C interface is selected, the MIS2DH allows choosing the least significant bit (LSB) of its I2C slave address using the SMD jumper labeled ADDR SEL. The MIS2DH also possesses two

interrupts, IN1 and IN2, routed to the PWM and INT pins on the mikroBUS™ socket, entirely programmed by the user through a serial interface. They signal the MCU that an event, such as inertial wake-up/free-fall or the board's position, has been sensed. This Click board™ can be operated only with a 3.3V logic voltage level. The board must perform appropriate logic voltage level conversion before using MCUs with different logic levels. Also, it comes equipped with a library containing functions and an example code that can be used as a reference for further development.

Accel 21 Click top side image
Accel 21 Click bottom side image

Features overview

Development board

EasyPIC v8 is a development board specially designed for the needs of rapid development of embedded applications. It supports many high pin count 8-bit PIC microcontrollers from Microchip, regardless of their number of pins, and 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 provides a fluid and immersive working experience, allowing access anywhere and under any

circumstances at any time. Each part of the EasyPIC v8 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-UART, USB DEVICE, and CAN 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 8-bit PIC MCUs, from the smallest PIC MCU devices with only eight up to forty pins. EasyPIC 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.

EasyPIC v8 horizontal image

Microcontroller Overview

MCU Card / MCU

PIC18LF46K40

Architecture

PIC

MCU Memory (KB)

64

Silicon Vendor

Microchip

Pin count

40

RAM (Bytes)

3728

Used MCU Pins

mikroBUS™ mapper

NC
NC
AN
NC
NC
RST
SPI Chip Select
RE0
CS
SPI Clock
RC3
SCK
SPI Data OUT
RC4
MISO
SPI Data IN
RC5
MOSI
Power Supply
3.3V
3.3V
Ground
GND
GND
Interrupt 1
RC0
PWM
Interrupt 2
RB0
INT
NC
NC
TX
NC
NC
RX
I2C Clock
RC3
SCL
I2C Data
RC4
SDA
NC
NC
5V
Ground
GND
GND
1

Take a closer look

Schematic

Accel 21 Click Schematic schematic

Step by step

Project assembly

EasyPIC v8 front image hardware assembly

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

EasyPIC v8 front image hardware assembly
Buck 22 Click front image hardware assembly
MCU DIP 40 hardware assembly
EasyPIC 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 Accel 21 Click driver.

Key functions:

  • accel21_set_config - Accel 21 set config function

  • accel21_get_axis - Accel 21 get accel data function

  • accel21_get_temperature - Accel 21 get temperature 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 main.c
 * @brief Accel 21 Click example
 *
 * # Description
 * This library contains API for Accel 21 Click driver.
 * The library initializes and defines the I2C or SPI bus drivers 
 * to write and read data from registers. 
 * The library also includes a function for reading X-axis, Y-axis, and Z-axis data. 
 *
 * The demo application is composed of two sections :
 *
 * ## Application Init
 * The initialization of I2C or SPI module, log UART, and additional pins. 
 * After the driver init, the app executes a default configuration,
 * checks communication and device ID. 
 *
 * ## Application Task
 * This example demonstrates the use of the Accel 21 Click board™.
 * Measures and displays acceleration data for X-axis, Y-axis, and Z-axis. 
 * Results are being sent to the UART Terminal, where you can track their changes.
 *
 * @author Nenad Filipovic
 *
 */

#include "board.h"
#include "log.h"
#include "accel21.h"

static accel21_t accel21;
static log_t logger;

void application_init ( void )
{
    log_cfg_t log_cfg;          /**< Logger config object. */
    accel21_cfg_t accel21_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.
    accel21_cfg_setup( &accel21_cfg );
    ACCEL21_MAP_MIKROBUS( accel21_cfg, MIKROBUS_1 );
    err_t init_flag = accel21_init( &accel21, &accel21_cfg );
    if ( ( I2C_MASTER_ERROR == init_flag ) || ( SPI_MASTER_ERROR == init_flag ) )
    {
        log_error( &logger, " Communication init." );
        for ( ; ; );
    }

    if ( ACCEL21_ERROR == accel21_default_cfg ( &accel21 ) )
    {
        log_error( &logger, " Default configuration." );
        for ( ; ; );
    }
    
    if ( ACCEL21_ERROR == accel21_check_id ( &accel21 ) )
    {
        log_printf( &logger, " Communication ERROR \r\n" );
        for ( ; ; );
    }

    log_info( &logger, " Application Task " );
    log_printf( &logger, "------------------------\r\n" );
    log_printf( &logger, "       Accel Data       \r\n" );
    log_printf( &logger, "------------------------\r\n" );
    Delay_ms( 100 ); 
}

void application_task ( void )
{
    static accel21_axis_t axis;
    accel21_get_axis( &accel21, &axis );
    log_printf( &logger, "\tX : %d \r\n\tY : %d \r\n\tZ : %d \r\n", axis.x, axis.y, axis.z );
    log_printf( &logger, "------------------------\r\n" );
    Delay_ms( 1000 );
}

void main ( void )
{
    application_init( );

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

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

Additional Support

Resources