For M0--Sample Code 5-Free fall detection function(freeFall.ino)
Last revision 2026/01/30
Requirements
- Hardware
- Firebeetle Board-M0 × 1
- LIS2DW12 Triple Axis Accelerometer ×1
- Jumper wires
- Software
- Arduino IDE
- Download and install the LIS Series Library and Sample Code (About how to install the library?)
- About how to use Firebeetle Board-M0?
Connection
Connect your sensor to an M0 controller (or others) according to the connection diagram below
Sample Code 5-Free fall detection function(freeFall.ino)
- Select freeFall.ino
- Program Burning
/**！
* @file freeFall.ino
* @brief Sensor module free fall detection, set the free fall time with the setFrDur() function to adjust the sensitivity of the detection.
* @n The shorter the free fall time we set, the easier for the module to detect the free fall event
* @n When using SPI, chip select pin can be modified by changing the value of LIS2DW12_CS
* @copyright Copyright (c) 2010 DFRobot Co.Ltd (http://www.dfrobot.com)
* @licence The MIT License (MIT)
* @author [fengli]([email protected])
* @version V1.0
* @date 2021-01-16
* @get from https://www.dfrobot.com
* @https://github.com/DFRobot/DFRobot_LIS
*/
#include <DFRobot_LIS2DW12.h>
//When using I2C communication, use the following program to construct an object by DFRobot_LIS2DW12_I2C
/*!
* @brief Constructor
* @param pWire I2c controller
* @param addr I2C address(0x18/0x19)
*/
//DFRobot_LIS2DW12_I2C acce(&Wire,0x18);
DFRobot_LIS2DW12_I2C acce;
//When using SPI communication, use the following program to construct an object by DFRobot_LIS2DW12_SPI
#if defined(ESP32) || defined(ESP8266)
#define LIS2DW12_CS D3
#elif defined(__AVR__) || defined(ARDUINO_SAM_ZERO)
#define LIS2DW12_CS 3
#elif (defined NRF5)
#define LIS2DW12_CS 2 //The pin on the development board with the corresponding silkscreen printed as P2
#endif
/*!
* @brief Constructor
* @param cs Chip selection pinChip selection pin
* @param spi SPI controller
*/
//DFRobot_LIS2DW12_SPI acce(/*cs = */LIS2DW12_CS);
//DFRobot_LIS2DW12_SPI acce(/*cs = */LIS2DW12_CS,&SPI);
void setup(void){
Serial.begin(9600);
while(!acce.begin()){
Serial.println("Communication failed, check the connection and I2C address setting when using I2C communication.");
delay(1000);
}
Serial.print("chip id : ");
Serial.println(acce.getID(),HEX);
//Chip soft reset
acce.softReset();
//Set whether to collect data continuously
acce.continRefresh(true);
/**！
Set power mode:
eHighPerformance_14bit /<High-Performance Mode,14-bit resolution>/
eContLowPwr4_14bit /<Continuous measurement,Low-Power Mode 4(14-bit resolution)>/
eContLowPwr3_14bit /<Continuous measurement,Low-Power Mode 3(14-bit resolution)>/
eContLowPwr2_14bit /<Continuous measurement,Low-Power Mode 2(14-bit resolution)/
eContLowPwr1_12bit /<Continuous measurement,Low-Power Mode 1(12-bit resolution)>/
eSingleLowPwr4_14bit /<Single data conversion on demand mode,Low-Power Mode 4(14-bit resolution)>/
eSingleLowPwr3_14bit /<Single data conversion on demand mode,Low-Power Mode 3(14-bit resolution)>/
eSingleLowPwr2_14bit /<Single data conversion on demand mode,Low-Power Mode 2(14-bit resolution)>/
eSingleLowPwr1_12bit /<Single data conversion on demand mode,Low-Power Mode 1(12-bit resolution)>/
eHighPerformanceLowNoise_14bit /<High-Performance Mode,Low-noise enabled,14-bit resolution>/
eContLowPwrLowNoise4_14bit /<Continuous measurement,Low-Power Mode 4(14-bit resolution,Low-noise enabled)>/
eContLowPwrLowNoise3_14bit /<Continuous measurement,Low-Power Mode 3(14-bit resolution,Low-noise enabled)>/
eContLowPwrLowNoise2_14bit /<Continuous measurement,Low-Power Mode 2(14-bit resolution,Low-noise enabled)>/
eContLowPwrLowNoise1_12bit /<Continuous measurement,Low-Power Mode 1(12-bit resolution,Low-noise enabled)>/
eSingleLowPwrLowNoise4_14bit /<Single data conversion on demand mode,Low-Power Mode 4(14-bit resolution),Low-noise enabled>/
eSingleLowPwrLowNoise3_14bit /<Single data conversion on demand mode,Low-Power Mode 3(14-bit resolution),Low-noise enabled>/
eSingleLowPwrLowNoise2_14bit /<Single data conversion on demand mode,Low-Power Mode 2(14-bit resolution),Low-noise enabled>/
eSingleLowPwrLowNoise1_12bit /<Single data conversion on demand mode,Low-Power Mode 1(12-bit resolution),Low-noise enabled>/
*/
acce.setPowerMode(DFRobot_LIS2DW12::eContLowPwr4_14bit);
/**！
Set the sensor data collection rate:
eRate_0hz /<Measurement off>/
eRate_1hz6 /<1.6hz, use only under low-power mode>/
eRate_12hz5 /<12.5hz>/
eRate_25hz
eRate_50hz
eRate_100hz
eRate_200hz
eRate_400hz /<Use only under High-Performance mode>/
eRate_800hz /<Use only under High-Performance mode>/
eRate_1k6hz /<Use only under High-Performance mode>/
eSetSwTrig /<The software triggers a single measurement>/
*/
acce.setDataRate(DFRobot_LIS2DW12::eRate_100hz);
/**！
Set the sensor measurement range:
e2_g /<±2g>/
e4_g /<±4g>/
e8_g /<±8g>/
e16_g /< ±16g>/
*/
acce.setRange(DFRobot_LIS2DW12::e2_g);
/**
* Set the free fall time (Or the number of free-fall samples. In a measurement, it will not be determined as a free-fall event unless the free-fall samples are sufficient.)
dur (0 ~ 31)
time = dur * (1/Rate)(unit:s)
| An example of a linear relationship between an argument and time |
|------------------------------------------------------------------------------------------------------------------------|
| | | | | |
| Data rate | 25 Hz | 100 Hz | 400 Hz | = 800 Hz |
|------------------------------------------------------------------------------------------------------------------------|
| time |dur*(1s/25)= dur*40ms| dur*(1s/100)= dur*10ms | dur*(1s/400)= dur*2.5ms | dur*(1s/800)= dur*1.25ms |
|------------------------------------------------------------------------------------------------------------------------|
*/
acce.setFreeFallDur(/*dur = */3);
/**！
Set the interrupt source of the int1 pin:
eDoubleTap(Double click)
eFreeFall(Free fall)
eWakeUp(wake)
eSingleTap(single-Click)
e6D(Orientation change check)
*/
acce.setInt1Event(DFRobot_LIS2DW12::eFreeFall);
delay(100);
}
void loop(void){
//Free fall event detected
if(acce.freeFallDetected()){
Serial.println("free fall detected");
delay(300);
}
}
Result
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