Example of free fall detection for LSM6DSO in X-NUCLEO-IKS01A3

Dependencies:   X_NUCLEO_IKS01A3

Free Fall Detection Demo Application with LSM6DSO based on sensor expansion board X-NUCLEO-IKS01A3

Main function is to show how to detect the free fall event using the sensor expansion board and send a notification using UART to a connected PC or Desktop and display it on terminal applications like TeraTerm.
After connection has been established:
- the user can try to leave falling the board and then view the notification using an hyper terminal. When the free fall is detected, the LED is switched on for a while.
- the user button can be used to enable/disable the free fall detection feature.

Revision:
0:f84262b9053f
Child:
5:4f3cf9d2ce1f
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/main.cpp	Wed Mar 06 13:29:13 2019 +0000
@@ -0,0 +1,107 @@
+/**
+ ******************************************************************************
+ * @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.
+ *
+ ******************************************************************************
+*/ 
+ 
+/* Includes */
+#include "mbed.h"
+#include "XNucleoIKS01A3.h"
+ 
+/* 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 LSM6DSOSensor *acc_gyro = mems_expansion_board->acc_gyro;
+ 
+InterruptIn mybutton(USER_BUTTON);
+DigitalOut myled(LED1);
+ 
+volatile int mems_event = 0;
+volatile int toggle_free_fall_enable = 0;
+static int free_fall_is_enabled = 1;
+ 
+/* User button callback. */
+void pressed_cb() {
+  toggle_free_fall_enable = 1;
+}
+ 
+/* Interrupt 1 callback. */
+void int1_cb() {
+  mems_event = 1;
+}
+ 
+/* Simple main function */
+int main() {
+  /* Attach callback to User button press */
+  mybutton.fall(&pressed_cb);
+  /* Attach callback to LSM6DSO INT1 */
+  acc_gyro->attach_int1_irq(&int1_cb);
+  
+  /* Enable LSM6DSO accelerometer */
+  acc_gyro->enable_x();
+  /* Enable Free Fall Detection. */
+  acc_gyro->enable_free_fall_detection();
+  
+  printf("\r\n--- Starting new run ---\r\n");
+ 
+  while(1) {
+    if(toggle_free_fall_enable) {
+      toggle_free_fall_enable = 0;
+      if(free_fall_is_enabled == 0) {
+        acc_gyro->enable_free_fall_detection();
+        free_fall_is_enabled = 1;
+      } else {
+        acc_gyro->disable_free_fall_detection();
+        free_fall_is_enabled = 0;
+      }
+    }
+ 
+    if (mems_event) {
+      mems_event = 0;
+      LSM6DSO_Event_Status_t status;
+      acc_gyro->get_event_status(&status);
+      if (status.FreeFallStatus) {
+        /* Led blinking. */
+        myled = 1;
+        wait(0.2);
+        myled = 0;
+ 
+        /* Output data. */
+        printf("Free Fall Detected!\r\n");
+      }
+    }
+  }
+}