topic Re: problem writting 2d arrays into SD card in Kinetis Design Studio

problem writting 2d arrays into SD card

arunkumar1989 — Sat, 16 May 2015 10:14:31 GMT

Hey guys,

I am having some problem writing 2D arrays into SD card.

Please consider the following example:

[code]

int16 Ringbuf[5][2] = { {0,0}, {1,2}, {2,4}, {3,6},{4,8}};

FAT1_f_printf(&fs,"%d,",Ringbuf[0,0); //random garbage is being written to file here.

[/code]

Any idea why this is happening?

I am using MK60MOVLQF15 CPU

Thanks,

Arun

Re: problem writting 2d arrays into SD card

BlackNight — Sat, 16 May 2015 10:41:18 GMT

Hi Arun,

I think I have not really used that printf() function.

printf() uses a lot of stack, make sure you have plenty stack space allocated.

Then, %d is for integer, probably 32bit on your microcontroller.

Use %hd instead (see printf - C++ Reference ).

Maybe this explains what is happening.

I hope this helps,

Erich

Re: problem writting 2d arrays into SD card

arunkumar1989 — Sat, 16 May 2015 11:17:34 GMT

no luck so far ,single dimensional arrays are working correctly,my problem is with 2D arrays,the manual also has no examples with 2D examples are given,is there any way around this?

FatFs - f_printf

Re: problem writting 2d arrays into SD card

BlackNight — Sat, 16 May 2015 11:36:43 GMT

if the array is one or two (or more) dimensional, really should not matter.

Anway, what you have pasted will not compile anyway, I think you wanted to have this:

FAT1_f_printf(&fs,"%d,",Ringbuf[0][0]); //random garbage is being written to file here.

The other thing to check: is your code warning-free?

Make sure you have included "Fat1.h" before using any function of it, especially functions with open argument lists.

Erich

Re: problem writting 2d arrays into SD card

arunkumar1989 — Sat, 16 May 2015 12:22:35 GMT

The warning at that line is this:

Description Resource Path Location Type

left-hand operand of comma expression has no effect [-Wunused-value] passing argument 1 of 'f_printf' from incompatible pointer type [enabled by default] sdcard.c /sdcard_150_v2/Sources line 55 C/C++ Problem

Re: problem writting 2d arrays into SD card

BlackNight — Sat, 16 May 2015 12:33:27 GMT

So is fs really of type FIL?

Re: problem writting 2d arrays into SD card

arunkumar1989 — Sat, 16 May 2015 12:42:42 GMT

Yes sir it is.

I am attaching the .c file for your reference.

This is what i am getting in the file:

536805384,

Re: problem writting 2d arrays into SD card

BlackNight — Sat, 16 May 2015 14:09:11 GMT

Change

FAT1_f_printf(&fs,"%d,",Ring[0,1]);

FAT1_f_printf(&fs,"%hd,",Ring[0][1]);

Re: problem writting 2d arrays into SD card

arunkumar1989 — Mon, 18 May 2015 04:16:11 GMT

Yes ,a silly typo from me ,thanks that did the trick.

Thanks a lot.