Hey everyone!
I've been trying to use the Adxl 375 Accelerometer by Adafruit and have encountered a road block.
event.acceleration.x
event.acceleration.y
event.acceleration.z
Give the output values interms of m/s^2. However for whatever reason, the maximum such value i obtain is 245 m/s^2 at each axes regardless of how hard / fast I throw the accelerometer to the ground. Where could I be possibly going wrong?
This was gotten from the example offset code from the adafruit adxl375 library.
Are you using appropriate size variables in the code you didn't post?
You forgot to set the correct g range.
Any idea how I could do this?
Library Reference | ADXL345 Digital Accelerometer | Adafruit Learning System
According to the above, I can only set it to 16 G.
Im not sure I understood you. What do you mean?
Are the variables in the code you didn't post big enough to contain the values you are calculating?
Make changes to the code you did not post.
This is the code, Im not sure what to do.
/* This example shows how to use the trimmer offset registers to account for any error in the sensor
and 'zero' out the flat reading to be 0, 0, 1g. note this is unique to each sensor so it'll have
to be repeated and 'saved' for each ADXL you use!
*/
#include <Wire.h>
#include <Adafruit_Sensor.h>
#include <Adafruit_ADXL375.h>
#define ADXL375_SCK 13
#define ADXL375_MISO 12
#define ADXL375_MOSI 11
#define ADXL375_CS 10
/* Assign a unique ID to this sensor at the same time /
/ Uncomment following line for default Wire bus */
Adafruit_ADXL375 accel = Adafruit_ADXL375(12345);
/* Uncomment for SPI */
//Adafruit_ADXL375 accel = Adafruit_ADXL375(ADXL375_SCK, ADXL375_MISO, ADXL375_MOSI, ADXL375_CS, 12345);
void setup(void)
{
Serial.begin(115200);
while (!Serial);
Serial.println("ADXL375 Offsets Test"); Serial.println("");
/* Initialise the sensor /
if(!accel.begin())
{
/ There was a problem detecting the ADXL343 ... check your connections /
Serial.println("Ooops, no ADXL375 detected ... Check your wiring!");
while(1);
}
/ Display some basic information on this sensor */
accel.printSensorDetails();
Serial.println("");
// init offsets to zero
accel.setTrimOffsets(0, 0, 0);
Serial.println("Hold accelerometer flat to set offsets to 0, 0, and -1g...");
delay(1000);
int16_t x, y, z;
x = accel.getX();
y = accel.getY();
z = accel.getZ();
Serial.print("Raw X: "); Serial.print(x); Serial.print(" ");
Serial.print("Y: "); Serial.print(y); Serial.print(" ");
Serial.print("Z: "); Serial.print(z); Serial.print(" ");Serial.println(" counts");
// the trim offsets are in 'multiples' of 4, we want to round, so we add 2
accel.setTrimOffsets(-(x+2)/4,
-(y+2)/4,
-(z-20+2)/4); // Z should be '20' at 1g (49mg per bit)
int8_t x_offset, y_offset, z_offset;
accel.getTrimOffsets(&x_offset, &y_offset, &z_offset);
Serial.print("Current trim offsets: ");
Serial.print(x_offset); Serial.print(", ");
Serial.print(y_offset); Serial.print(", ");
Serial.println(z_offset);
Serial.println();
}
void loop(void)
{
/* Get a new sensor event */
sensors_event_t event;
accel.getEvent(&event);
/* Display the results (acceleration is measured in m/s^2) */
Serial.print("X: "); Serial.print(event.acceleration.x); Serial.print(" ");
Serial.print("Y: "); Serial.print(event.acceleration.y); Serial.print(" ");
Serial.print("Z: "); Serial.print(event.acceleration.z); Serial.print(" ");
Serial.println("m/s^2 ");
Serial.print("Raw X: "); Serial.print(accel.getX()); Serial.print(" ");
Serial.print("Y: "); Serial.print(accel.getY()); Serial.print(" ");
Serial.print("Z: "); Serial.print(accel.getZ()); Serial.print(" ");
Serial.println(" counts");
Serial.println();
delay(500);
}
Sorry, This is the code, Im not too sure what you meant
/* This example shows how to use the trimmer offset registers to account for any error in the sensor
and 'zero' out the flat reading to be 0, 0, 1g. note this is unique to each sensor so it'll have
to be repeated and 'saved' for each ADXL you use!
*/
#include <Wire.h>
#include <Adafruit_Sensor.h>
#include <Adafruit_ADXL375.h>
#define ADXL375_SCK 13
#define ADXL375_MISO 12
#define ADXL375_MOSI 11
#define ADXL375_CS 10
/* Assign a unique ID to this sensor at the same time /
/ Uncomment following line for default Wire bus */
Adafruit_ADXL375 accel = Adafruit_ADXL375(12345);
/* Uncomment for SPI */
//Adafruit_ADXL375 accel = Adafruit_ADXL375(ADXL375_SCK, ADXL375_MISO, ADXL375_MOSI, ADXL375_CS, 12345);
void setup(void)
{
Serial.begin(115200);
while (!Serial);
Serial.println("ADXL375 Offsets Test"); Serial.println("");
/* Initialise the sensor /
if(!accel.begin())
{
/ There was a problem detecting the ADXL343 ... check your connections /
Serial.println("Ooops, no ADXL375 detected ... Check your wiring!");
while(1);
}
/ Display some basic information on this sensor */
accel.printSensorDetails();
Serial.println("");
// init offsets to zero
accel.setTrimOffsets(0, 0, 0);
Serial.println("Hold accelerometer flat to set offsets to 0, 0, and -1g...");
delay(1000);
int16_t x, y, z;
x = accel.getX();
y = accel.getY();
z = accel.getZ();
Serial.print("Raw X: "); Serial.print(x); Serial.print(" ");
Serial.print("Y: "); Serial.print(y); Serial.print(" ");
Serial.print("Z: "); Serial.print(z); Serial.print(" ");Serial.println(" counts");
// the trim offsets are in 'multiples' of 4, we want to round, so we add 2
accel.setTrimOffsets(-(x+2)/4,
-(y+2)/4,
-(z-20+2)/4); // Z should be '20' at 1g (49mg per bit)
int8_t x_offset, y_offset, z_offset;
accel.getTrimOffsets(&x_offset, &y_offset, &z_offset);
Serial.print("Current trim offsets: ");
Serial.print(x_offset); Serial.print(", ");
Serial.print(y_offset); Serial.print(", ");
Serial.println(z_offset);
Serial.println();
}
void loop(void)
{
/* Get a new sensor event */
sensors_event_t event;
accel.getEvent(&event);
/* Display the results (acceleration is measured in m/s^2) */
Serial.print("X: "); Serial.print(event.acceleration.x); Serial.print(" ");
Serial.print("Y: "); Serial.print(event.acceleration.y); Serial.print(" ");
Serial.print("Z: "); Serial.print(event.acceleration.z); Serial.print(" ");
Serial.println("m/s^2 ");
Serial.print("Raw X: "); Serial.print(accel.getX()); Serial.print(" ");
Serial.print("Y: "); Serial.print(accel.getY()); Serial.print(" ");
Serial.print("Z: "); Serial.print(accel.getZ()); Serial.print(" ");
Serial.println(" counts");
Serial.println();
delay(500);
}
And now with code tags, please. 
Please edit your posts to add code tags.
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