cant' open SD card file

[salahenp]

Hi,
I want to use my ESP32 board to write on my SD card. using the example that comes with the esp32 board package, all things are OK. But when I wrote my own code, It can not open the file to write in it.

Code: Select all

#include "FS.h"
#include "SD.h"
#include "SPI.h"


bool sdInitSuccess = false;
#define SDWRITETIME 60000
char CurrentFileName[128];


#define SD_CS_PIN 5      // Le lecteur de SD card sera branché sur les pins G5 (CS)


bool sdfileOpend = false;    

void WriteSDcard()
 {
  File myFile;
  static unsigned long T = 0;
  if(!sdInitSuccess){
    Serial.println("Initializing SD card...");
    if (!SD.begin()) {
      Serial.println("Initialization failed!\n");
      return;
     }  //failure
     else {
      Serial.println("Intitialization success.\n");
      sdInitSuccess = true;
    }
  }
  if (millis() < T) return;
  T = millis() + SDWRITETIME;
  char FileName[128];
  char fileHeader[] = "Date;Time;T1;H1;T2;H2";

  sprintf(FileName, "test30.txt");

  if (strcmp(CurrentFileName, FileName)) {
    strcpy(CurrentFileName, FileName);
    
    }

   if (sdfileOpend == 0) {
    bool myFileExist = SD.exists("test30.txt");
    myFile = SD.open("test30.txt", FILE_WRITE);
Serial.println(myFileExist);
Serial.println(myFile);
    // if (myFile) {
      
    // }
      if(!myFile) {
      Serial.print("can not open File for Writing:  ");
      Serial.println(CurrentFileName);
      return;
    }
    Serial.print(F("File opened for Writing successfully:"));
      sdfileOpend = 1;
      if (!myFileExist) {
        myFile.println(fileHeader);
        
      }
    Serial.println(CurrentFileName);
  }
  if(myFile.print(16))
  Serial.println("Written");
  else
  Serial.println("Failed to write");
  myFile.print("/");
  myFile.print(10);
  myFile.print("/");
  myFile.print(2023);
  myFile.print(";");
  myFile.print(10);
  myFile.print(":");
  myFile.print(48);
  myFile.print(":");
  myFile.print(7);
  myFile.print(";");
  myFile.print(40);
  myFile.print(";");
  myFile.print(35);
  myFile.print(";");
  myFile.print(3);
  myFile.print(";");
  myFile.print(2.5);
  myFile.print(";");
  myFile.print(40);
  myFile.print(";");
  myFile.print(25);
  myFile.print(";");
  myFile.print(30);
  myFile.print(";");
  myFile.print(35);
  myFile.print(";");
  myFile.print(45);
  myFile.print(";");
  myFile.print(20);
  myFile.print(";");
  
  myFile.close();
  sdfileOpend = 0;
  Serial.println("Data written to SD card");
 } 


void setup() {
  // put your setup code here, to run once:
Serial.begin(115200);
  
}

void loop() {

  WriteSDcard();
  // put your main code here, to run repeatedly:

}

The output give me:

Code: Select all

Initializing SD card...
Intitialization success.

0
0
can not open File for Writing:  test30.txt
0
0
can not open File for Writing:  test30.txt

I use VSPI, beacause HSPI is reserved for other modules.

what could be the problem?

[lbernstone]

Filenames need to be absolute. Start with a slash.

[salahenp]

Filenames need to be absolute. Start with a slash.

Thank you very much, That solved it. I didn't know that before. With Arduino boards I never used the slash.