Achieve real-time, tailor-made pressure measurements with BM1390GLV-Z and PIC18F45K42

Reliable, accurate, and easy to use – our digital pressure sensor is the solution you've been waiting for

Published Nov 01, 2023

Click board™

Pressure 17 Click

Dev. board

EasyPIC v7

Compiler

NECTO Studio

MCU

PIC18F45K42

Discover how digital pressure sensors are revolutionizing industries with unparalleled accuracy and real-time data insights

Hardware Overview

How does it work?

Pressure 17 Click is based on the BM1390GLV-Z, ultra-compact piezoresistive pressure sensor from Rohm Semiconductor. This MEMS-based absolute pressure sensor includes a sensing element, analog-to-digital converter, signal processing part, and digital interface that sends the digital pressure data to the host controller. The MEMS-based sensing element measures pressure from 300hPa up to 1300hPa with an accuracy of ±1hPa over a wide operating temperature range at the industry’s lowest power. It also has a built-in

temperature compensation function that internally performs temperature compensation for MEMS inside the chip, so it’s easy to get pressure information, built-in FIFO, and operation in a temperature range of -40°C to 85°C, which ensures stable operation under extreme conditions. Pressure 17 Click communicates with MCU using the standard I2C 2-Wire interface to read data and configure settings, supporting Standard Mode operation with a clock frequency of 100kHz and Fast Mode up to 400kHz. It also

possesses an additional interrupt signal, routed on the INT pin of the mikroBUS™ socket labeled as INT, indicating when a specific interrupt event occurs. 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.

Features overview

Development board

EasyPIC v7 is the seventh generation of PIC development boards specially designed to develop embedded applications rapidly. It supports a wide range of 8-bit PIC microcontrollers from Microchip and has a broad set of unique functions, such as a powerful onboard mikroProg programmer and In-Circuit debugger over USB-B. The development board is well organized and designed so that the end-user has all the necessary elements in one place, such as switches, buttons, indicators, connectors, and others. With four different connectors for each port, EasyPIC v7 allows you to connect accessory boards, sensors, and custom electronics more efficiently than ever. Each part of

the EasyPIC v7 development board contains the components necessary for the most efficient operation of the same board. An integrated mikroProg, a fast USB 2.0 programmer with mikroICD hardware In-Circuit Debugger, offers many valuable programming/debugging options and seamless integration with the Mikroe software environment. Besides it also includes a clean and regulated power supply block for the development board. It can use various external power sources, including an external 12V power supply, 7-23V AC or 9-32V DC via DC connector/screw terminals, and a power source via the USB Type-B (USB-B) connector. Communication options such as

USB-UART and RS-232 are also included, alongside the well-established mikroBUS™ standard, three display options (7-segment, graphical, and character-based LCD), and several different DIP sockets. These sockets cover a wide range of 8-bit PIC MCUs, from PIC10F, PIC12F, PIC16F, PIC16Enh, PIC18F, PIC18FJ, and PIC18FK families. EasyPIC v7 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.

Microcontroller Overview

MCU Card / MCU

Architecture

PIC

MCU Memory (KB)

Silicon Vendor

Microchip

Pin count

RAM (Bytes)

2048

Used MCU Pins

mikroBUS™ mapper

RST

SCK

MISO

MOSI

Power Supply

3.3V

Ground

GND

PWM

Interrupt

RB0

INT

I2C Clock

RC3

SCL

I2C Data

RC4

SDA

Ground

GND

Take a closer look

Click board™ Schematic

Step by step

Project assembly

EasyPIC v7 front image hardware assembly

Start by selecting your development board and Click board™. Begin with the EasyPIC v7 as your development board.

NECTO Output Selection Step Image hardware assembly

In the advanced settings, pay special attention to the Redirect standard output field. By default, it is set to Application output as the method of displaying final results. To show results via a UART terminal, select the “UART” option in that field and click the “SAVE” button. You will be returned to the Compiler field, and now you can move on to the next step by pressing the “NEXT” button.

GNSS2 Click front image hardware assembly

EasyPIC v7 Access MB 1 - upright/background hardware assembly

NECTO Compiler Selection Step Image hardware assembly

Necto DIP image step 7 hardware assembly

EasyPIC PRO v7a Display Selection 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 Pressure 17 Click driver.

Key functions:

pressure17_get_int_pin - This function returns the INT pin logic state
pressure17_read_data - This function checks if the data is ready and then reads the pressure and temperature raw data and converts them to millibar and Celsius respectfully
pressure17_write_register - This function writes a data byte to the selected register by using I2C serial interface

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 Pressure17 Click example
 *
 * # Description
 * This example demonstrates the use of Pressure 17 Click board by reading and displaying 
 * the pressure and temperature data.
 *
 * The demo application is composed of two sections :
 *
 * ## Application Init
 * Initializes the driver and performs the Click default configuration.
 *
 * ## Application Task
 * Waits for the data ready interrupt and then reads the pressure [mbar] and temperature [C] data
 * and displays the results on the USB UART approximately every 200ms.
 *
 * @author Stefan Filipovic
 *
 */

#include "board.h"
#include "log.h"
#include "pressure17.h"

static pressure17_t pressure17;
static log_t logger;

void application_init ( void ) 
{
    log_cfg_t log_cfg;  /**< Logger config object. */
    pressure17_cfg_t pressure17_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.
    pressure17_cfg_setup( &pressure17_cfg );
    PRESSURE17_MAP_MIKROBUS( pressure17_cfg, MIKROBUS_1 );
    if ( I2C_MASTER_ERROR == pressure17_init( &pressure17, &pressure17_cfg ) ) 
    {
        log_error( &logger, " Communication init." );
        for ( ; ; );
    }
    
    if ( PRESSURE17_ERROR == pressure17_default_cfg ( &pressure17 ) )
    {
        log_error( &logger, " Default configuration." );
        for ( ; ; );
    }
    
    log_info( &logger, " Application Task " );
}

void application_task ( void ) 
{
    if ( !pressure17_get_int_pin ( &pressure17 ) )
    {
        float pressure, temperature;
        if ( PRESSURE17_OK == pressure17_read_data ( &pressure17, &pressure, &temperature ) )
        {
            log_printf ( &logger, " Pressure: %.2f mbar\r\n Temperature: %.2f C\r\n\n", pressure, temperature );
        }
    }
}

int main ( void ) 
{
    /* Do not remove this line or clock might not be set correctly. */
    #ifdef PREINIT_SUPPORTED
    preinit();
    #endif
    
    application_init( );
    
    for ( ; ; ) 
    {
        application_task( );
    }

    return 0;
}

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