Hnp Htha

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8 years, 12 months ago.

Data Accel

Please help me how can I read data accelerometer from this Library? I need use mbed read data LIS3DH by I2C. This is my code I try but it is not working.

include the mbed library with this snippet

#include "mbed.h"
#include "LIS3DH.h"
Serial pc(USBTX, USBRX);    //Tx, Rx


I2C i2c(p28,p27);
LIS3DH data(i2c, 0x19);
float dt_usr[3];
float x,y,z;

int main ()
{
pc.baud(115200);
while (1) {
    //x=data.read_data(*dt_usr[0]);
    //y=data.read_data(*dt_usr[1]);
    //z=data.read_data(*dt_usr[2]);
    data.read_data(dt_usr);
    x=dt_usr[0];
    //y=dt_usr[1];
    //z=dt_usr[2];
    printf(" %f \n\r", x);
    //printf(" %f \n\r", y);
    //printf(" %f \n\r", z);
    //wait(1.0);
    }
}

Thank you very much!

Question relating to:

Last updated: 23 Aug 2017
LIS3DH / STMicroelectronics / MEMS motion sensor, 3-axis accelerometer library I2C, LIS3DH

2 Answers

Georgios Moralis
8 years, 12 months ago.

You probably need to use the initialize method of the LIS3DH class.

Kenji Arai
8 years, 12 months ago.

Hi Hnp,
Thank you for your interest the lib.
I have tried your program on my Nucleo F411 mbed board with following modification.
It works (You don't need any additional initialize method).

modification

//I2C i2c(p28,p27);
I2C i2c(D14,D15);  // Pin names for F411 mbed
//LIS3DH data(i2c, 0x19);
LIS3DH data(i2c, 0x18 << 1); // SDO/SA0 = GND (my HW connection)

This means you need to set address "0x19 << 1".
My LIS3H SDO/SA0 pin connected to GND but I think you connected to VCC.
Please shift one bit or just use "LIS3DH_V_CHIP_ADDR".
Make sure your address pin, SDO/SA0 condition.
Kenji