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Can't reach 1000 Hz output data rate for H3LIS331DL Accelerometer sensor

AGHAZ.1
Associate

As the datasheet of H3LIS331DL has a 1000 Hz output data rate which means 1 reading every 1 millisecond, and that what is required in my project, I am using an I2C connection and having the period between two readings 3 to 4 milliseconds, the code is as follow :

#include "SparkFun_LIS331.h"
#include <Wire.h>
 
LIS331 xl;
unsigned long startMillis;  
unsigned long currentMillis;
void setup() 
{
  Wire.begin();
  xl.setI2CAddr(0x19);    // This MUST be called BEFORE .begin() so 
 
   //  .begin() can communicate with the chip
  xl.begin(LIS331::USE_I2C); // Selects the bus to be used and sets
                          //  the power up bit on the accelerometer.
                          //  Also zeroes out all accelerometer
                          //  registers that are user writable.
xl.axesEnable(true);
 
  xl.setPowerMode(LIS331::NORMAL);
  xl.setODR(LIS331::DR_1000HZ);
  
startMillis = millis();  //initial start time
  
  
  Serial.begin(115200);
  
}
 
void loop() 
{
  int16_t x, y, z;
   currentMillis = millis();
    xl.readAxes(x, y, z);  // The readAxes() function transfers the
 Serial.print(currentMillis - startMillis);Serial.print(",");
 
    Serial.print(xl.convertToG(100,x)); Serial.print(","); // The convertToG() function
    Serial.print(xl.convertToG(100,y)); Serial.print(","); // accepts as parameters the
    Serial.println(xl.convertToG(100,z)); // Serial.println(", ");// raw value and the current
  startMillis = currentMillis;
}

The Output Result:

0693W00000QKOhhQAH.jpgcould you please help me to have 1 reading every 1 milisecond.

Thanks

2 REPLIES 2
KnarfB
Principal III

The serial port baud rate is a limiting factor. Calculate how many chars/s you can print.

hth

KnarfB

Thank you for your reply. Could you please tell me how to do it �� , and is there any way to overcome the baud rate limitation so the sensor output data rate can reach 1 kHz,

I decreased the baud rate, and the interval between two readings increased, but when I increased the baud rate, the interval would stay3 to 4 even when the baud rate on 2000000.