Temperature logger - date as filename

Projects Programming
1

Hello!
I know it has been long dicussed and a lot of posts have been made about logging to SD card and saving the file as date/time. But I still can't manage to get it work. I am using Arduino Duemilanove with Uno bootloader, SD card module, LM35 temperature sensor and Adafruit DS3231 clock module.

So this is my simplified code, which works:

#include <RTClib.h>
#include <SD.h>
#include <SPI.h>
RTC_DS3231 rtc;
int val;
int tempPin = 1;
File myfile;

void setup () {
    if (!SD.begin(10)) {while (1);}
    myfile = SD.open("TEMPERATURE.TXT", FILE_WRITE);
}

void loop () {
    DateTime now = rtc.now();

    val = analogRead(tempPin);
    float mv = ( val/1024.0)*5000;
    float tempc = mv/10;

    myfile.print(now.hour(), DEC);
    myfile.print(":");
    myfile.print(now.minute(), DEC);
    myfile.print(" ");
    myfile.println(tempc,DEC);
    myfile.close();
    delay(100000);
}

At the moment it is saving all data into single file, but I would like to make each day a new file.

Something like:

File myfile;
char fileName[12];
sprintf(fileName, "%d%02d%02d.txt", year, month, day);

void setup () {
    getFileName();
    myfile = SD.open(filename, FILE_WRITE);  
    myfile.println(",");
    myfile.close();  
}

void loop () {
    getFileName();
    day = bcdToDec(now.day());
    month = bcdToDec(now.month());
    year = bcdToDec(now.year());

    myfile = SD.open(filename, FILE_WRITE);
    myfile.print("testing123");
    myfile.close();
}
2

Here is some code with some of the irrelevant stuff deleted. No library is used for the RTC. No changes required for DS3231.

#include <OneWire.h>
#include <DallasTemperature.h>
#include <PCD8544.h>             
#include "Wire.h"                
#include <SD.h>
#include <SPI.h>                 

#define DS1307_ADDRESS 0x68

char filename[] = "00000000.CSV";
File myFile;

static PCD8544 lcd;

//_________________________________________

void setup() {
  lcd.begin(84, 48);
  
  Wire.begin();
  Serial.begin(9600);
  Serial2.begin(9600);
  
      GetClock();
    today = day; // flag for later midnight check
    getFileName();
      lcd.setCursor(0,3); 
      lcd.println(filename);
        delay(2000);
     
  }
//________________________________________________________________

void loop() {
     
   GetClock();
  if (today != day)
  {
   today = day;
   getFileName(); 

  
  }
  }  
    while (Serial2.available()) 
  {
    delay(3);  
    char c = Serial2.read();
    readString += c; 
  }// end while

  if (readString.length() >0) 
  {  
    getDump();   
   readString="";  
   } // end if
  
  sensors.requestTemperatures();

  power();
  StringOut();
  LCDdata();

  k=k+1;  
  if ((k>9 ) && flowRate > 1)
  {   
    WriteSD(); 
    k=0;

    p=p+1;  
  if (p>90)
     {
       supply = InTemp;
       p=0;
     }
      
  if (OutTemp>maxOut)
     {
        maxOut = OutTemp;
     }
  }      
   pulseCount=0;
   attachInterrupt(sensorInterrupt, pulseCounter, FALLING);
  }
}  // loop ends here



byte bcdToDec(byte val)  {
  // Convert binary coded decimal to normal decimal numbers
  return ( (val/16*10) + (val%16) );
}

void getFileName(){
sprintf(filename, "%02d%02d%02d.csv", year, month, day);
sprintf(dailydate, "%02d%02d%02d", year, month, day);
}

void GetClock(){
  // Reset the register pointer
  Wire.beginTransmission(DS1307_ADDRESS);
  byte zero = 0x00;
  Wire.write(zero);
  Wire.endTransmission();
  Wire.requestFrom(DS1307_ADDRESS, 7);

  second = bcdToDec(Wire.read());
  minute = bcdToDec(Wire.read());
  hour = bcdToDec(Wire.read() & 0b111111); //24 hour time
  weekDay = bcdToDec(Wire.read()); //0-6 -> sunday - Saturday
  day = bcdToDec(Wire.read());
  month = bcdToDec(Wire.read());
  year = bcdToDec(Wire.read());
}
3

Thank you! But I still can't get it work. Can someone please look my testcode:

#include <RTClib.h>
#include <SD.h>
#include <SPI.h>
RTC_DS3231 rtc;
char filename[] = "00000000.CSV";
File myfile;
void setup () {
Serial.begin(9600);
if (!SD.begin(10)) {while (1); }
if (! rtc.begin()) {Serial.println("Couldn't find RTC"); Serial.flush(); abort(); }
if (rtc.lostPower()) { Serial.println("RTC lost power, let's set the time!"); }
}
void loop () {
DateTime now = rtc.now();
sprintf(filename, "%02d%02d%02d.csv", now.day(), now.month(), now.year());
myfile = SD.open(filename, FILE_WRITE);
myfile.println("This is test.");
myfile.close();
delay(3000);
}

4

I can't comment any further because I don't know anything about the RTC library, but I notice that you are not defining the the clock,

#define DS1307_ADDRESS 0x68

which I imagine is a requirement irrespective of the library.

5

Thank you. I managed to get it work using my last posted code.