Chan's FatFS read problem!

Al pacino D. OP #680357 
Hello my friends,

I'm really confused about the Chan's FatFS read-function!
I'm able to write and do loggings etc... but reading a file greater than 
1 kB doesn't work! I can read up to 1 kB (not including 1 kB).

The problem is I see only 0 (zero) above 1 kB!
My buffer is 2 kB, so it's not the bufferproblem.
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int main()

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{

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  FATFS Fs;

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  FIL FileObject;

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  char data[2048];

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  const char* FileName = "0:Basic.bin";  

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  unsigned int ByteToRead = sizeof(data);

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  unsigned int ByteRead;

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  unsigned char SD = 0;

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  memset(data, 0, sizeof(data));

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  if( f_mount(SD, &Fs) != FR_OK )

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    return 0;

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  if(f_open(&FileObject, FileName, FA_OPEN_EXISTING|FA_READ) != FR_OK)

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    return 0;

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  FRESULT res;

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  int f, e; f = e = 0;

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  while(1)

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  {    

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    res = f_read(&FileObject, data, ByteToRead, &ByteRead);

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    if(res == FR_OK)

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    {

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      f++;     //just to check number of cycles

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      if(ByteRead == 0) break;

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      e++;

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    }

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  }

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  return 0;

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}
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holger Guest #680423 
I am missing two things in your code:
disk_initialize ()  How does it work without this ?
f_close()

I would try to read 2048 bytes in four 512 byte steps.
Only to see if f_read() has a problem reading more than
one sector.
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Al pacino D. OP #680429 
holger wrote:
> I am missing two things in your code:
> disk_initialize ()  How does it work without this ?
> f_close()
>
> I would try to read 2048 bytes in four 512 byte steps.
> Only to see if f_read() has a problem reading more than
> one sector.

Holger,

disk_initialize() is done when you call f_open().

f_close? hmmm I thought this was only needed when you write to SD, for 
flushing the data. But maybe it also works for reading! I'll try that.

So f_read() reads only 512 bytes max.?? I thought as long as the buffer 
can be filled.

Thank you.
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holger Guest #680441 
>But what if I want to
>know how big the file is, so I know when to stop copying to the buffer?

Ask FileObject.fsize ?
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