Dear all, After implementing file system on both 1Gb Nand Flash & 4Gb Nand Flash, using LPC1788, i found that the minimum size of any created file was as follows: 1Gb - 8KB 4Gb - 16KB
I want to decrease the file size to 4KB only. If you know any possible way, kindly highlight. I tried to search for any related document in keil's documentation but could not come across one. The minimum size of a page in both the Nand Flash is 2KB (incase this data is of any relevance).
Regards, Dhaval
Is it simply that the cluster size is increasing as the disk size increasing?
Though it looks like so, have no assurity about this. I haven't come across any document that comments on the minimum size of the created/saved file.
What do you actually mean by "minimum size of the created/saved file"? are you suggesting that if you, for example, create a file of 10 bytes, then on reading it back it has been expanded to the minimum value? If you are, then this would clearly be wrong.
Or are you saying that a 10 byte file is consuming a minimum amount of space on the file system? Which would suggest something akin to a cluster size.
Ya. You got it.
in 1Gb Nand Flash, i created some files to check this. Below are the details:
Before creating files No files...File System Directory... 120.078.336 bytes free. After creating files File System Directory... . <DIR> 01.01.2011 12:00 .. <DIR> 01.01.2011 12:00 Android.txt 460 01.01.2011 12:00 Beta.txt 430 01.01.2011 12:00 CupCake.txt 460 01.01.2011 12:00 Donut.txt 440 01.01.2011 12:00 Eclair.txt 450 01.01.2011 12:00 Froyo.txt 440 01.01.2011 12:00 GingerBread.txt 500 01.01.2011 12:00 HoneyComb.txt 480 01.01.2011 12:00 Ice-cream.txt 480 01.01.2011 12:00 JellyBean.txt 480 01.01.2011 12:00 10 File(s) 4.620 bytes 2 Dir(s) 119.980.032 bytes free.
120.078.336 bytes - 119.980.032 bytes = 96KB Total Files + Total directories = 12 96/12 = 8KB each. Even though each file has less number of bytes (460bytes on average), the number of free byte suggests otherwise. This is one small experiment. I have also done few more experiments before finally concluding this.
same goes with 4Gb Nand Flash, each file(/directory) occupies 16KB minimum.
I also edited the file to store more bytes and found that unless the stored data bytes does not the minimum size, the number of free bytes remains unchanged. And the number of free bytes decrease if the data stored in the file exceeds the minimum size.