Microcontroller Libraries for SD Card and FAT File System

If you want read a SD/MMC card with a 8 bit or even 16 bit Microchip PIC or dsPIC microcontroller, you need use some of the available libraries, but they have a high Flash and Ram usage! Here you can see an overview about the available libraries and how much memory they demand.

The Microchip Libraries for Applications (MLA) is the 'oficial' and free library from the vendor that provides SD/MMC card and FAT file system support, but there are others libraries, paid and free, like the MikroC and Petit FatFs. But how can you know if these libraries will fit in your microcontroller memory? below you can see a table with some tests and have an idea:

Library	Compiler	Compiler Version	Flash	RAM	Microcontroller	File System
MLA	XC16	Free (without optimization)	37k	1,2k	dsPIC33EP512MU810	FAT32
MLA*	Microchip C30	Free (without optimization)	42k	1,5k	24FJ128GA010	FAT32
MikroC	MikroC PRO for PIC	PRO (Full)	19,8k	1,15k	P18F45K22	FAT16
MikroC	MikroC PRO for dsPIC	PRO (Full)	10k	1,4k	dsPIC30F4013	FAT16
Petit FAT File System v0.03	Microchip C30	Free (without optimization)	15k	0,4k	24FJ64GA002	FAT16/32

*Old MLA library (note the C30, the newer uses XC16)

As we can see no one can fit in the cheap and widely used 16F628A, 16F877A or even the cheapest dsPIC like the 33FJ12GP201. But attention to the Petit FatFs that allows on its configuration file enable/disable some features, so for example, if you just enable the SD card read and FAT32, the flash needed will be about 10k (Microchip C30 compiler with optimization level 3), fitting in the dsPIC33FJ12GP201 that has 12k of flash memory.

Now you can choose the proper microcontroller before your project gets stucked due the memory limitations!