I am currently data loggin MPU6050 by using lowlatencylogger from SDFat and it can give me very good sampling rate. My only problem is whenever I want to stop data logging I need to key in any character on serial monitor to stop which is not applicable since during data logging my arduino is not connected to pc.
If I just switch off the power there is only temporary file inside the sd card, i guess it means it has not truncate and convert to bin file. So the method i am using now is change the FILE_BLOCK_COUNT to a smaller number and stop logging earlier. But this is not a practical way.
So how can I truncate the temporary file after I switch off the arduino?
the code as follow:
#include <SPI.h>
#include <SdFat.h>
#include <SdFatUtil.h>
#include "Wire.h"
#include "I2Cdev.h"
#include "MPU6050.h"
#include "UserDataType.h" // Edit this include file to change data_t.
MPU6050 mpu;
MPU6050 mpu_69 (0x69);
void setupData() {
#if I2CDEV_IMPLEMENTATION == I2CDEV_ARDUINO_WIRE
Wire.begin();
// set I2C 400 kHz
TWBR = (F_CPU/400000 - 16)/2;
Serial.println(F("Using Wire"));
#elif I2CDEV_IMPLEMENTATION == I2CDEV_BUILTIN_FASTWIRE
Fastwire::setup(400, true);
Serial.println(F("Using Fastwire"));
#endif
mpu.initialize();
mpu_69.initialize();
}
// Acquire a data record.
void acquireData(data_t* data) {
data->time = micros();
mpu.getMotion6(&data->axr, &data->ayr, &data->azr,
&data->gxr, &data->gyr, &data->gzr);
mpu_69.getMotion6(&data->axl, &data->ayl, &data->azl,
&data->gxl, &data->gyl, &data->gzl);
}
// setup AVR I2C
// Print a data record.
void printData(Print* pr, data_t* data) {
pr->print(data->time);
pr->write(',');
pr->print(data->axr);
pr->write(',');
pr->print(data->ayr);
pr->write(',');
pr->print(data->azr);
pr->write(',');
pr->print(data->gxr);
pr->write(',');
pr->print(data->gyr);
pr->write(',');
pr->print(data->gzr);
pr->write(',');
pr->print(data->axl);
pr->write(',');
pr->print(data->ayl);
pr->write(',');
pr->print(data->azl);
pr->write(',');
pr->print(data->gxl);
pr->write(',');
pr->print(data->gyl);
pr->write(',');
pr->println(data->gzl);
}
// Print data header.
void printHeader(Print* pr) {
pr->println(F("micros,axr,ayr,azr,gxr,gyr,gzr,axl,ayl,azl,gxl,gyl,gzl"));
}
//==============================================================================
// Start of configuration constants.
//==============================================================================
//Interval between data records in microseconds.
const uint32_t LOG_INTERVAL_USEC = 10000;
//------------------------------------------------------------------------------
// Pin definitions.
//
// SD chip select pin.
const uint8_t SD_CS_PIN = 8;
//
// Digital pin to indicate an error, set to -1 if not used.
// The led blinks for fatal errors. The led goes on solid for SD write
// overrun errors and logging continues.
const int8_t ERROR_LED_PIN = -1;
//------------------------------------------------------------------------------
// File definitions.
//
// Maxrimum file size in blocks.
// The program creates a contiguous file with FILE_BLOCK_COUNT 512 byte blocks.
// This file is flash erased using special SD commands. The file will be
// truncated if logging is stopped early.
const uint32_t FILE_BLOCK_COUNT = 100;
////////////////////////////////////////////////////////////
////////////////////////////////////////////////////////////
void setup(void) {
if (ERROR_LED_PIN >= 0) {
pinMode(ERROR_LED_PIN, OUTPUT);
}
Serial.begin(38400);
sd.begin(38400);
while (!Serial) {}
Serial.print(F("FreeRam: "));
Serial.println(FreeRam());
Serial.print(F("Records/block: "));
Serial.println(DATA_DIM);
if (sizeof(block_t) != 512) {
error("Invalid block size");
}
setupData();
// initialize file system.
if (!sd.begin(SD_CS_PIN, SPI_FULL_SPEED)) {
sd.initErrorPrint();
fatalBlink();
}
}
//------------------------------------------------------------------------------
void loop(void) {
logData();
binaryToCsv();
}
And I guess SDfat owner will be so mad on my ignorance but I really not familiar this. So please help?
