teensy-sdfat/SdFat/examples/LowLatencyLoggerMPU6050/UserFunctions.cpp

// User data functions.  Modify these functions for your data items.
#include "UserTypes.h"
#include "Wire.h"
#include "I2Cdev.h"
#include "MPU6050.h"
//------------------------------------------------------------------------------
MPU6050 mpu;
static uint32_t startMicros;
// Acquire a data record.
void acquireData(data_t* data) {
  data->time = micros();
  mpu.getMotion6(&data->ax, &data->ay, &data->az, 
                 &data->gx, &data->gy, &data->gz);
}

// setup AVR I2C
void userSetup() {
#if I2CDEV_IMPLEMENTATION == I2CDEV_ARDUINO_WIRE
  Wire.begin();
  Wire.setClock(400000);
#elif I2CDEV_IMPLEMENTATION == I2CDEV_BUILTIN_FASTWIRE
  Fastwire::setup(400, true);
#endif
  mpu.initialize();  
}

// Print a data record.
void printData(Print* pr, data_t* data) {
  if (startMicros == 0) {
    startMicros = data->time;
  }
  pr->print(data->time- startMicros);
  pr->write(',');
  pr->print(data->ax);
  pr->write(',');
  pr->print(data->ay);
  pr->write(',');
  pr->print(data->az);
  pr->write(',');
  pr->print(data->gx);
  pr->write(',');
  pr->print(data->gy);
  pr->write(',');
  pr->println(data->gz);
}

// Print data header.
void printHeader(Print* pr) {
  startMicros = 0;
  pr->println(F("micros,ax,ay,az,gx,gy,gz"));
}