I can only write to SD card once (SPI-fatfs)

[NBlac]

I am using a stm32f407 and i use this code inside a loop:

/* Mount SD Card */
 if(f_mount(&fs, "", 0) != FR_OK)
 _Error_Handler(__FILE__, __LINE__);
 
 /* Open file to write */
 if(f_open(&fil, "first.txt", FA_OPEN_ALWAYS | FA_READ | FA_WRITE) != FR_OK)
 _Error_Handler(__FILE__, __LINE__);
 
 /* Check free space */
 if(f_getfree("", &fre_clust, &pfs) != FR_OK)
 _Error_Handler(__FILE__, __LINE__);
 
 total = (uint32_t)((pfs->n_fatent - 2) * pfs->csize * 0.5);
 fre = (uint32_t)(fre_clust * pfs->csize * 0.5); 
 
 /* Free space is less than 1kb */
 if(fre < 1)
 _Error_Handler(__FILE__, __LINE__); 
 
 /* Writing text */
	sprintf(counter_buff, "%.10f", count);
	 f_puts("\n", &fil); 
 f_puts("STM32 SD Card I/O Example via SPI\n", &fil); 
 f_puts(counter_buff, &fil);
	 f_puts("\n", &fil); 
 
 /* Close file */
 if(f_close(&fil) != FR_OK)
 _Error_Handler(__FILE__, __LINE__); 
 
 /* Open file to read */
 if(f_open(&fil, "first.txt", FA_READ) != FR_OK)
 _Error_Handler(__FILE__, __LINE__);
 
 while(f_gets(buffer, sizeof(buffer), &fil))
 {
 //printf("%s", buffer);
 }
 
 /* Close file */
 if(f_close(&fil) != FR_OK)
 _Error_Handler(__FILE__, __LINE__); 
 
 /* Unmount SDCARD */
 if(f_mount(NULL, "", 1) != FR_OK)
 _Error_Handler(__FILE__, __LINE__); 
 HAL_GPIO_TogglePin(GPIOE, GPIO_PIN_0);

When i open the file from the sd card on my pc i only see this:

1.35

STM32 SD Card I/O Example via SPI

1.35

The led keeps on toggling so the code is running.

Any ideas?

thanks

[Tesla DeLorean]

What is it supposed to do in your mind?

If you want it to add lines, perhaps f_seek() to the end of the file.

How does the count advance? Is it really a float?

 if (f_open(&fil, "LOG.TXT", FA_OPEN_ALWAYS | FA_WRITE) == FR_OK)
 {
 UINT BytesWritten;
 const char string[] = "Another line gets added\r\n";
 
 f_lseek(&fil, f_size(&fil));
 f_write(&fil, string, strlen(string), &BytesWritten);
 f_close(&fil);
 } 

[NBlac]

I thought that just by adding "f_puts("\n", &fil);" it would change line and next data would be written after that. But now i realized it doesn't. I used your code for writing to the card and it works great.

thanks a lot