File content as of revision 15:913ecebcc7ed:

/**
 ******************************************************************************
 * @file    main.cpp
 * @author  SRA
 * @version V1.0.0
 * @date    5-March-2019
 * @brief   Simple Example application for using the X_NUCLEO_IKS01A3
 *          MEMS Inertial & Environmental Sensor Nucleo expansion board.
 ******************************************************************************
 * @attention
 *
 * <h2><center>&copy; COPYRIGHT(c) 2019 STMicroelectronics</center></h2>
 *
 * Redistribution and use in source and binary forms, with or without modification,
 * are permitted provided that the following conditions are met:
 *   1. Redistributions of source code must retain the above copyright notice,
 *      this list of conditions and the following disclaimer.
 *   2. Redistributions in binary form must reproduce the above copyright notice,
 *      this list of conditions and the following disclaimer in the documentation
 *      and/or other materials provided with the distribution.
 *   3. Neither the name of STMicroelectronics nor the names of its contributors
 *      may be used to endorse or promote products derived from this software
 *      without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
 *  SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
 * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 ******************************************************************************
*/

/*
    LELEC2811 Altimeter LPS22HH Project
    M. Lefebvre - 2019-2020
*/

/* Includes */
#include <stdlib.h>
#include <time.h>
#include "mbed.h"
#include "XNucleoIKS01A3.h"
#include "stm32l073xx.h"
#include "stm32l0xx_hal_flash.h"

/* Defines */
#define FS                      10.0    // Readout frequency (Hz)

// LPS22HH Pressure sensor
#define P0                      1013.26 // Sea level pressure (hPa)
#define LPS22HH_ODR             10.0    // Output data rate (one-shot, 1, 10, 25, 50, 75, 100, 200 Hz)
#define LPS22HH_LOW_NOISE_EN    1       // Low-noise (0 disabled, 1 enabled)
#define LPS22HH_LPF_CFG         3       // Device bandwidth (0 for ODR/2, 2 for ODR/9, 3 for ODR/20)
#define LPS22HH_DATA_SIZE       8       // Number of bytes for LPS22HH pressure sensor data

/* Functions definition */
bool acquisition_task(bool verbose);
void read_task();
void print_flash_info();
bool erase_flash(bool verbose);
bool write_flash(uint32_t Flash_addr, uint32_t* Flash_wdata, int32_t n_words, bool verbose);
void read_flash(uint32_t Flash_addr, uint32_t* Flash_rdata, uint32_t n_bytes);
void button1_enabled_cb(void);
void button1_onpressed_cb(void);
static char *print_double(char *str, double v);
float pressure_to_altitude(double pressure);
uint32_t FloatToUint(float n);
float UintToFloat(uint32_t n);

/* Serial link */
Serial pc(SERIAL_TX, SERIAL_RX);

/* Button */
InterruptIn button1(USER_BUTTON);
volatile bool button1_pressed = false; // Used in the main loop
volatile bool button1_enabled = true; // Used for debouncing
Timeout button1_timeout; // Used for debouncing

/* Instantiate the expansion board */
static XNucleoIKS01A3 *mems_expansion_board = XNucleoIKS01A3::instance(D14, D15, D4, D5, A3, D6, A4);

/* Retrieve the composing elements of the expansion board */
static LIS2MDLSensor *magnetometer = mems_expansion_board->magnetometer;
static HTS221Sensor *hum_temp = mems_expansion_board->ht_sensor;
static LPS22HHSensor *press_temp = mems_expansion_board->pt_sensor;
static LSM6DSOSensor *acc_gyro = mems_expansion_board->acc_gyro;
static LIS2DW12Sensor *accelerometer = mems_expansion_board->accelerometer;
static STTS751Sensor *temp = mems_expansion_board->t_sensor;

/* Main */
int main()
{
    uint8_t id;
    float read_reg, read_reg_1;
    uint8_t read_reg_int, read_reg_int_1, read_reg_int_2;
    
    bool save_data = false;
    uint32_t Flash_addr = FLASH_BANK2_BASE;

    /* Serial link configuration */
    pc.baud(115200);
    
    /* Button configuration */
    button1.fall(callback(button1_onpressed_cb)); // Attach ISR to handle button press event
    
    /* Reset message */
    printf("\n\r**************************************************\n\r");
    printf("LELEC2811 LPS22HH Altimeter Program\n\r");
    printf("**************************************************\n\r");
    
    /* LPS22HH pressure sensor configuration */
    press_temp->enable();
    printf("/***** LPS22HH pressure sensor configuration *****/\r\n");
    
    press_temp->read_id(&id);
    printf("LPS22HH pressure = 0x%X\r\n", id);
    
    press_temp->set_odr(LPS22HH_ODR, LPS22HH_LOW_NOISE_EN);
    press_temp->get_odr(&read_reg, &read_reg_int);
    printf("LPS22HH ODR = %1.1f [Hz]\r\n", read_reg);
    printf("LPS22HH LOW_NOISE_EN = %1d\r\n", read_reg_int);
    
    press_temp->set_lpfp_cfg(LPS22HH_LPF_CFG);
    press_temp->get_lpfp_cfg(&read_reg_int);
    printf("LPS22HH LPF_CFG = %1d\r\n", read_reg_int);
    
    /* Print Flash memory information */
    print_flash_info();
    
    /* Information for the user */
    printf("Press blue button to start data acquisition\r\n");
    printf("Press 'R' to read previously measured data\r\n");
    
    /* Acquisition loop */
    while(1) {
        // Start saving data when button is pushed
        if (button1_pressed) {
            button1_pressed = false;
            save_data = true;
            erase_flash(false);
            printf("Acquiring data...\r\n");
            printf("Press blue button to stop data acquisition\r\n");
            Flash_addr = FLASH_BANK2_BASE;
        }
        
        if (save_data) {
            // Acquisition task
            save_data = acquisition_task(false);
        }
        else {
            // Read task
            read_task();
        }
    }
}

/* Acquisition task */
bool acquisition_task(bool verbose)
{
    float pressure_value, alt_value;
    
    uint32_t buffer_size = FLASH_PAGE_SIZE/4;
    uint32_t data_ind = 0;
    uint32_t data_buffer[buffer_size];
    
    uint32_t Flash_addr = FLASH_BANK2_BASE;

    while (Flash_addr <= FLASH_BANK2_END-FLASH_PAGE_SIZE+1) {
        // Read sensors data
        press_temp->get_pressure(&pressure_value);
        alt_value = pressure_to_altitude(pressure_value);
        
        // Write page in Flash memory
        if (data_ind >= buffer_size) {
            write_flash(Flash_addr, &data_buffer[0], buffer_size, false);
            Flash_addr += FLASH_PAGE_SIZE;
            data_ind = 0;
        }
            
        // Write data to buffer
        data_buffer[data_ind] = FloatToUint(pressure_value);
        data_buffer[data_ind+1] = FloatToUint(alt_value);
        data_ind = data_ind+2;
        
        // Print data in terminal
        if (verbose) {
            printf("LPS22HH: [press/mbar] %1.6f, [alt/m] %1.6f\r\n", pressure_value, alt_value);
        }
        
        // Wait for acquisition period
        wait(1/FS);
        
        // Stop saving data when button is pushed
        if (button1_pressed) {
            button1_pressed = false;
            // Save remaining data to Flash memory
            write_flash(Flash_addr, &data_buffer[0], data_ind, false);
            printf("Data acquisition stopped\r\n");
            printf("Press 'R' to read the data\r\n");
            return false;
        }
    }
    printf("Data acquisition stopped\r\n");
    printf("Press 'R' to read the data\r\n");
    return false;
}

/* Read task */
void read_task()
{
    char pc_input;
    uint32_t Flash_rdata[2];
    bool flash_empty = false;
    
    // Read terminal input
    if (pc.readable()) {
        pc_input = pc.getc();
    }
    else {
        pc_input = ' ';
    }
    
    // Read Flash memory if 'R' is pressed
    if ((pc_input == 'r') || (pc_input == 'R')) {
        // Data labels
        printf("press\talt\r\n");
        
        // Read 1st Flash data
        uint32_t Flash_addr_temp = FLASH_BANK2_BASE;
        read_flash(Flash_addr_temp, &Flash_rdata[0], LPS22HH_DATA_SIZE);
        
        // Read Flash data
        while ((Flash_addr_temp <= FLASH_BANK2_END-LPS22HH_DATA_SIZE+1) && !flash_empty) {
            // Print read data in the terminal
            printf("%1.6f\t%1.6f\r\n", UintToFloat(Flash_rdata[0]), UintToFloat(Flash_rdata[1]));
            Flash_addr_temp += LPS22HH_DATA_SIZE;
            
            // Check if the next address is not empty (erased Flash only contains 0)
            if (Flash_addr_temp <= FLASH_BANK2_END-LPS22HH_DATA_SIZE+1) {
                read_flash(Flash_addr_temp, &Flash_rdata[0], LPS22HH_DATA_SIZE);
                if ((Flash_rdata[0] == 0) && (Flash_rdata[1] == 0)) {
                    flash_empty = true;
                }
            }
        }
    }
}

/* Print Flash memory info */
void print_flash_info()
{
    printf("**************************************************\n\r");
    printf("/***** Flash memory info *****/\r\n");
    printf("Flash size: %d [B]\r\n", FLASH_SIZE);
    printf("Flash page size: %d [B]\r\n", FLASH_PAGE_SIZE);
    printf("Flash nb of pages: %d \r\n", FLASH_SIZE/FLASH_PAGE_SIZE);
    printf("Flash bank 1 base address: 0x%X\r\n", FLASH_BASE);
    printf("Flash bank 1 end address: 0x%X\r\n", FLASH_BANK1_END);
    printf("Flash bank 2 base address: 0x%X\r\n", FLASH_BANK2_BASE);
    printf("Flash bank 2 end address: 0x%X\r\n", FLASH_BANK2_END);
    printf("**************************************************\n\r");
}

/* Erase content of Flash memory */
bool erase_flash(bool verbose)
{
    printf("Erasing Flash memory...\r\n");
    
    // Unlock Flash memory
    HAL_FLASH_Unlock();

    // Erase Flash memory
    FLASH_EraseInitTypeDef eraser;
    uint32_t Flash_addr = FLASH_BANK2_BASE;
    uint32_t page_error = 0;
    int32_t page = 1;
    
    while (Flash_addr < FLASH_BANK2_END) {
        eraser.TypeErase = FLASH_TYPEERASE_PAGES;
        eraser.PageAddress = Flash_addr;
        eraser.NbPages = 1;
        if(HAL_OK != HAL_FLASHEx_Erase(&eraser, &page_error)) {
            if (verbose) {printf("Flash erase failed!\r\n");}
            printf("Error 0x%X\r\n", page_error);
            HAL_FLASH_Lock();
            return false;
        }
        if (verbose) {printf("Erased page %d at address: 0x%X\r\n", page, Flash_addr);}
        Flash_addr += FLASH_PAGE_SIZE;
        page++;
    }
    
    if (verbose) {printf("Flash erase succesful!\r\n");}
    return true;
}

/* Write Flash memory */
bool write_flash(uint32_t Flash_addr, uint32_t* Flash_wdata, int32_t n_words, bool verbose)
{
    clock_t time;
    if (verbose) {time = clock();}
    
    // Unlock Flash memory
    HAL_FLASH_Unlock();
    
    // Write Flash memory
    for (int i=0; i<n_words; i++) {
        if (HAL_OK != HAL_FLASH_Program(FLASH_TYPEPROGRAM_WORD, Flash_addr, Flash_wdata[i])) {
            if (verbose) {printf("Flash write failed!\r\n");}
            HAL_FLASH_Lock();
            return false;
        }
        Flash_addr += 4;
    }
    if (verbose) {printf("Flash write succesful!\r\n");}
    
    HAL_FLASH_Lock();
    
    if (verbose) {
        time = clock() - time;
        printf("Time to write: %1.6f [s]\r\n", (((double) time)/CLOCKS_PER_SEC));
    }
    
    return true;
}

/* Read Flash memory */
void read_flash(uint32_t Flash_addr, uint32_t* Flash_rdata, uint32_t n_bytes)
{
    memcpy(Flash_rdata, (uint32_t*) Flash_addr, n_bytes);
}

/* Enables button when bouncing is over */
void button1_enabled_cb(void)
{
    button1_enabled = true;
}

/* ISR handling button pressed event */
void button1_onpressed_cb(void)
{
    if (button1_enabled) { // Disabled while the button is bouncing
        button1_enabled = false;
        button1_pressed = true; // To be read by the main loop
        button1_timeout.attach(callback(button1_enabled_cb), 0.3); // Debounce time 300 ms
    }
}

/* Helper function for printing floats & doubles */
static char *print_double(char *str, double v)
{
    int decimalDigits = 6;
    int i = 1;
    int intPart, fractPart;
    int len;
    char *ptr;

    /* prepare decimal digits multiplicator */
    for (; decimalDigits != 0; i *= 10, decimalDigits--);

    /* calculate integer & fractinal parts */
    intPart = (int)v;
    fractPart = (int)((v - (double)(int)v) * i);

    /* fill in integer part */
    sprintf(str, "%i.", intPart);

    /* prepare fill in of fractional part */
    len = strlen(str);
    ptr = &str[len];

    /* fill in leading fractional zeros */
    for (i /= 10; i > 1; i /= 10, ptr++) {
        if (fractPart >= i) {
            break;
        }
        *ptr = '0';
    }

    /* fill in (rest of) fractional part */
    sprintf(ptr, "%i", fractPart);

    return str;
}

/* Pressure to altitude conversion */
float pressure_to_altitude(double pressure)
{
    return 44330.77 * (1-pow(pressure/P0, 0.1902632));
}

uint32_t FloatToUint(float n)
{
   return (uint32_t)(*(uint32_t*)&n);
}
 
float UintToFloat(uint32_t n)
{
   return (float)(*(float*)&n);
}