Hey
I am using the datalogger example from the sd library with the teensy 3.5:
it takes between 5-20ms for each saving routine. Is that normal? Is it possible to do faster savings?
Thanks
I am using the datalogger example from the sd library with the teensy 3.5:
Code:
/*
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, pin 7 on Teensy with audio board
** MISO - pin 12
** CLK - pin 13, pin 14 on Teensy with audio board
** CS - pin 4, pin 10 on Teensy with audio board
created 24 Nov 2010
modified 9 Apr 2012
by Tom Igoe
This example code is in the public domain.
*/
#include <SD.h>
#include <Metro.h>
Metro data_exchange=Metro(5);
uint32_t time1, time2;
// On the Ethernet Shield, CS is pin 4. Note that even if it's not
// used as the CS pin, the hardware CS pin (10 on most Arduino boards,
// 53 on the Mega) must be left as an output or the SD library
// functions will not work.
// change this to match your SD shield or module;
// Arduino Ethernet shield: pin 4
// Adafruit SD shields and modules: pin 10
// Sparkfun SD shield: pin 8
// Teensy audio board: pin 10
// Teensy 3.5 & 3.6 on-board: BUILTIN_SDCARD
// Wiz820+SD board: pin 4
// Teensy 2.0: pin 0
// Teensy++ 2.0: pin 20
const int chipSelect = BUILTIN_SDCARD;
void setup()
{
// Open serial communications and wait for port to open:
Serial.begin(9600);
while (!Serial) {
; // wait for serial port to connect. Needed for Leonardo only
}
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:
return;
}
Serial.println("card initialized.");
}
void loop()
{
// 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 += ",";
}
}
// open the file. note that only one file can be open at a time,
// so you have to close this one before opening another.
File dataFile = SD.open("datalog.txt", FILE_WRITE);
// if the file is available, write to it:
if (dataFile) {
dataFile.println(dataString);
dataFile.close();
// print to the serial port too:
Serial.println(dataString);
}
// if the file isn't open, pop up an error:
else {
Serial.println("error opening datalog.txt");
}
time2=time1;
time1=millis();
if(data_exchange.check()){
Serial.println(time1-time2);
}
}
Thanks