Source Code - Data Collection

/*

  SD card datalogger

 This example shows how to log data from three analog sensors

 to an SD card using the SD library.

 The circuit:

 * analog sensors on analog ins 0, 1, and 2

 * SD card attached to SPI bus as follows:

 ** MOSI - pin 11

 ** MISO - pin 12

 ** CLK - pin 13

 ** CS - pin 4 (for MKRZero SD: SDCARD_SS_PIN)

 created  24 Nov 2010

 modified 9 Apr 2012

 by Tom Igoe

 This example code is in the public domain.

 */

#include <SPI.h>

#include <SD.h>

#include "MPU9250.h"

#define AHRS true         // Set to false for basic data read

#define SerialDebug true  // Set to true to get Serial output for debugging

// Pin definitions

int intPin = 12;  // These can be changed, 2 and 3 are the Arduinos ext int pins

int myLed  = 13;  // Set up pin 13 led for toggling

MPU9250 myIMU;

const int chipSelect = 8;

File dataFile;

void setup() {

  // Open serial communications and wait for port to open:

  Wire.begin();

  Serial.begin(38400);

  //while (!Serial) {

    ; // wait for serial port to connect. Needed for native USB port only

  pinMode(intPin, INPUT);

  digitalWrite(intPin, LOW);

  pinMode(myLed, OUTPUT);

  digitalWrite(myLed, HIGH);

  myIMU.initAK8963(myIMU.magCalibration);

  //}

  // Max out the gyroscope range

  myIMU.writeByte(MPU9250_ADDRESS, 27, 0b00011000);

  // Max out the accelerometer range

  //myIMU.writeByte(MPU9250_ADDRESS, 28, 0b00011000);

  Serial.print("Initializing SD card...");

  // see if the card is present and can be initialized:

  if (!SD.begin(chipSelect)) {

    Serial.println("Card failed, or not present");

    // don't do anything more:

    while (1);

  }

  Serial.println("card initialized.");

  dataFile = SD.open("datalog.csv", FILE_WRITE);

}

void loop() {

  long t = millis();

  if (myIMU.readByte(MPU9250_ADDRESS, INT_STATUS) & 0x01)

  {  

    myIMU.readAccelData(myIMU.accelCount);  // Read the x/y/z adc values

    myIMU.getAres();

    // Now we'll calculate the accleration value into actual g's

    // This depends on scale being set

    myIMU.ax = (float)myIMU.accelCount[0]*myIMU.aRes; // - accelBias[0];

    myIMU.ay = (float)myIMU.accelCount[1]*myIMU.aRes; // - accelBias[1];

    myIMU.az = (float)myIMU.accelCount[2]*myIMU.aRes; // - accelBias[2];

    myIMU.readGyroData(myIMU.gyroCount);  // Read the x/y/z adc values

    myIMU.getGres();

    // Calculate the gyro value into actual degrees per second

    // This depends on scale being set

    myIMU.gx = (float)myIMU.gyroCount[0];

    myIMU.gy = (float)myIMU.gyroCount[1];

    myIMU.gz = (float)myIMU.gyroCount[2];

    myIMU.readMagData(myIMU.magCount);  // Read the x/y/z adc values

    myIMU.getMres();

    // User environmental x-axis correction in milliGauss, should be

    // automatically calculated

    myIMU.magbias[0] = +470.;

    // User environmental x-axis correction in milliGauss TODO axis??

    myIMU.magbias[1] = +120.;

    // User environmental x-axis correction in milliGauss

    myIMU.magbias[2] = +125.;

    myIMU.mx = (float)myIMU.magCount[0]*myIMU.mRes*myIMU.magCalibration[0] -

               myIMU.magbias[0];

    myIMU.my = (float)myIMU.magCount[1]*myIMU.mRes*myIMU.magCalibration[1] -

               myIMU.magbias[1];

    myIMU.mz = (float)myIMU.magCount[2]*myIMU.mRes*myIMU.magCalibration[2] -

               myIMU.magbias[2];

  }

  myIMU.updateTime();

  // make a string for assembling the data to log:

  /*String dataString = "";

  // read three sensors and append to the string:

  for (int analogPin = 0; analogPin < 3; analogPin++) {

    int sensor = analogRead(analogPin);

    dataString += String(sensor);

    if (analogPin < 2) {

     dataString += ",";

    }

  }*/

  String ax = String(myIMU.ax);

  String ay = String(myIMU.ay);

  String az = String(myIMU.az);

  String gx = String(myIMU.gx);

  String gy = String(myIMU.gy);

  String gz = String(myIMU.gz);

  String mx = String(myIMU.mx);

  String my = String(myIMU.my);

  String mz = String(myIMU.mz);

  String data = String(ax+","+ay+","+az+","+gx+","+gy+","+gz/*+","+mx+","+my+","+mz*/);

  // open the file. note that only one file can be open at a time,

  // so you have to close this one before opening another.

  // if the file is available, write to it:

  if (dataFile) {

    dataFile.println(data);

    // print to the serial port too:

    Serial.print(data);

    Serial.print(" ");

    Serial.println(myIMU.gRes);

  }

  // if the file isn't open, pop up an error:

  else {

    Serial.println("error opening datalog.txt");

  }

  if (t>15000){

    dataFile.close();

  }

}