SPI SD卡FATFS创建文件问题？

晓枫VS枯叶

创建txt文件返回OK，写入数据也返回OK，读数据同样返回OK，并且数据和写入的一样，但是关闭文件卸载SD卡 后插在PC上却显示什么都没有，单独读卡里的txt文件也能读取上一次写进去的数据。
请问下有谁遇到过，读写代码如下：
#include "main.h"

FIL fnew; /* file objects */
FATFS fs; /* Work area (file system object) for logical drives */
FRESULT res; 
UINT br, bw;             /* File R/W count */
BYTE buffer[4096]={0};        /* file copy buffer */
BYTE textFileBuffer[] = "Welcome to use Wildfire iso stm32 Development Board today is a good day";

int main(void)
{
  // Define gpio input pin config structure SW.
  SystemCoreClockUpdate();
  
  hardware_init();
  delay_init();
  f_mount(&fs,"0:",0);
  res = f_open(&fnew, "0:/SD.txt", FA_CREATE_ALWAYS | FA_WRITE );
  
  if ( res == FR_OK )
  {
    res = f_write(&fnew, textFileBuffer, sizeof(textFileBuffer), &bw);
    f_close(&fnew);      
  }
  
  res = f_open(&fnew, "0:/SD.txt", FA_OPEN_EXISTING | FA_READ);  
  res = f_read(&fnew, buffer, sizeof(buffer), &br); 
  printf("this is a demo\r\n  ");
  printf("%d", buffer);
  
  /* Close open files */
 res= f_close(&fnew);                                      
  
  /* Unregister work area prior to discard it */
  f_mount(NULL,"0:",0 );
  
  while(1)
  {
  }
}

正点原子

没遇到过这个问题。

毛小毛

楼主 你改一下文件名试试  比如res = f_open(&fnew, "SD.txt", FA_CREATE_ALWAYS | FA_WRITE );