How to creat a file in SD card using MQX MFS?

[botaoyang]

I am trying to use MFS to creat a file in SD card ,

I have run the demo project mfs_sdcard twrk60d100m, it does not  work; then I add a line

"

fd_ptr = fopen("a:myfile.txt","w+");

"

in the project(this is learned from the MQX MFS Manual), this does not work too.

so I am preatty confused of using the MFS to creat a file.

I am using TWR K60D100m, Codewarrior10.6, MQX4.1

[DavidS]

Hi Botao,

Please review the C:\Freescale\Freescale_MQX_4_1_1\demo\web_hvac project.

It has option to log data to USB stick but the process would be same if modified to use SD Card.

I'm attaching the logging_task.c file for reference.

Note it uses "a" and not "w+".  I think I recall that version of MQX might have had issue with using "w+".

Regards,

David

[botaoyang]

Now， I think my problem can be more specific.

By my understanding, the process of using MFS over SD card is like this :

(1)   install ESDHC driver;

(2)   get the device pointer of SD card;

(3)   install MFS over SD card;

(4)   use MFS;

In this order, I have write a test MQX project, the main progress is as follows. the test result is I can not open the MFS by using this "MFS_fd = fopen("a:",NULL);", also the MFS installing progress returns a  successful result wihout insert a SD card. still creating a file in SD card is failed, even using "a".

I am seeking the cause of this problem desperately, please pay enough attention to my question and give me same useful tips. I am anxious of this , for this problem have delayed the progress of my project.

thank you very much.

   FILE_PTR esdhc_fd,MFS_fd;

   ESDHC_COMMAND_STRUCT command;

   bool sdhc;

   _mqx_int        error_code;

   uint32_t        param,rca,sector;

   uint8_t         buffer[512];

   printf("*********************************\n");

   printf("******sd card test project*******\n");

   printf("*********************************\n");

   esdhc_fd = fopen("esdhc:",NULL);

   if(NULL==esdhc_fd)

   {

       printf("open esdhc failed.\n");

   }

   else

   {

       printf("open esdhc successed.\n");

   }

   /* Initialize and detect card */

   if (ESDHC_OK != ioctl (esdhc_fd, IO_IOCTL_ESDHC_INIT, NULL))

   {

       printf("init esdhc failed.\n");

   }

   else

   {

       printf("init esdhc successed.\n");

   }

   /* SDHC check */

   sdhc = FALSE;

   param = 0;

   if (ESDHC_OK != ioctl (esdhc_fd, IO_IOCTL_ESDHC_GET_CARD, &param))

   {

       printf("find no sd card.\n");

   }

   if ((ESDHC_CARD_SD == param) || (ESDHC_CARD_SDHC == param) || (ESDHC_CARD_SDCOMBO ==

   param) || (ESDHC_CARD_SDHCCOMBO == param))

   {

   if ((ESDHC_CARD_SDHC == param) || (ESDHC_CARD_SDHCCOMBO == param))

   {

       sdhc = TRUE;

       printf("find a sd card.\n");

   }

   }

   else

   {

   /* Not SD memory card */

       printf("find no sd card.\n");

   }

   /* Install MFS over SD card driver */

   error_code = _io_mfs_install(esdhc_fd, "a:", (_file_size)0);

   if ((error_code != MFS_NO_ERROR)&&(error_code != MFS_NOT_A_DOS_DISK))

   {

       printf("Error initializing MFS: %s\n", MFS_Error_text((uint32_t)error_code));

   }

   else

   {

       printf("intalll MFS over SD card successed.\n");

   }

   MFS_fd = fopen("a:",NULL);

   if(NULL==MFS_fd)

   {

       printf("open MFS failed.\n");

   }

   else

   {

       printf("open MFS successed.\n");

   }

   fopen("a:myfile.txt","a");