How to sum up all the value in SD file.

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1

Hi, I would like to sum all the value that I save from text.txt file.

example: Save/text.txt

inside the text is:

1 2 3 3 2 3 2 1...3 2 1 = depending on the number of values i've input ?

#include <SPI.h>
#include <SD.h>
File myFile;
void setup()
{
  Serial.print("Initializing SD card...");
  pinMode(10, OUTPUT);
  if (!SD.begin(4)) {
    Serial.println("initialization failed!");
    return;
  }
  Serial.println("initialization done.");
}
void loop()
{

  char c=Serial.read()
    if(c=='H')          //input value
    {
      if(!SD.exists(text.txt))    
      {
        myFile = SD.open(text.txt);     //Write .txt file in SD, done.
        if (myFile) {
          myFile.println("2");
          myFile.close();
        }
      }
    }

  if(c=='L')          //input value
  {
    if(!SD.exists(text.txt))    
    {
      myFile = SD.open(text.txt);     //Write .txt file in SD, done.
      if (myFile) {
        myFile.println("3");
        myFile.close();
      }
    }
  }

  if(c=='S')
  {
    myFile = SD.open(text.txt);
    //[i]then sum-up all the values that is input in text.txt[/i]
  }
}
2

The basics can be found here:
http://forum.arduino.cc/index.php?topic=158438.0

3

thank you sir mrburnette :smiley: solved

4

but then using I2C, i got problem.

seems i can't pass the bufs value of from loop() to void requestEvent() to pass it to master using Wire.h.

void loop()
{
  if(s=='H')
  {
     myFile = SD.open("test.txt");
    if (myFile) {
      Serial.println("test.txt:");
      while (myFile.available()) {
        S1 = myFile.parseInt();
        a=a+S1-0;
      }
        Serial.print(a); //it can display the total sum of test.txt value.
      myFile.close();
    } 
    sprintf(bufs,"sum:%lu",a); //the value of bufs will be pass for I2C com. but i can't get it.
  }
  a='\0';
 delay(5000);
}

void requestEvent()
{
  Wire.write(bufs);
}

#include <Wire.h>
#include <SPI.h>
#include <SD.h>
int S1;
char i;
int a=0;
void setup()
{
Wire.begin(5);
Wire.onReceive(receiveEvent);
Wire.onRequest(requestEvent);
while (!Serial) {
;
}
Serial.print("Initializing SD card...");
pinMode(10, OUTPUT);
if (!SD.begin(4)) {
Serial.println("initialization failed!");
return;
}
Serial.println("initialization done.");
randomSeed(analogRead(0));
lcd.print("Initialization done");
delay(2000);
}
void loop()
{
if(s=='H') //from void receiveEvent(int howMany)
{
myFile = SD.open("test.txt");
if (myFile) {
Serial.println("test.txt:");
while (myFile.available()) {
S1 = myFile.parseInt();
a=a+S1-0;
Serial.print(S1);
}
Serial.print(a);
myFile.close();
}
sprintf(bufs,"sum:%lu",a);

}
a='\0';
delay(5000);
}
void receiveEvent(int howMany)
{
while(Wire.available() > 0)
{
char c = Wire.read();
numbers[i++] = c;
numbers*='\0';*

  • }*
    if (strcmp (numbers,"A")==0) {
  • {*
  • s='H'; //pass to void loop()*
  • }*
    }
    void requestEvent()
    {
  • Wire.write(bufs); // i can't get the bufs value from void loop().*
    }
    it can display the total sum from test.txt file after summing up to Serial monitor but i need to get the value and display to master.
    i can't pass the value from slave to master.
5

here's my first code, which is not in void loop(). but when i send data "A" from master to trigger,

my problem is it hang and nothing happen. help.

char bufs[70];
int S1;
int a=0;
void setup()
{
// SD initialization
}
void loop()
{
//no code here, all the codes are in void receiveEvent(int howMany)
} 

void receiveEvent(int howMany)
{
  while(Wire.available() > 0)
  {
    char c = Wire.read();
    numbers[i++] = c;
    numbers='\0';
  }
 if (strcmp (numbers,"A")==0) {
     
     myFile = SD.open("test.txt");

    if (myFile) {
      Serial.println("test.txt:");
      while (myFile.available()) {
        S1 = myFile.parseInt();
        a=a+S1-0;
        Serial.print(S1);
      }
        Serial.print(a);
      myFile.close();
    } 
    sprintf(bufs,"sum:%lu",a);
   
  }
}
void requestEvent()
{
  Wire.write(bufs);     
a='\0';
}