SDHC (FAT32 for SD cards)

[Normnet]

IF (Your PIC is running at 40Mhz) AND (You are using the DEFINE FS_SPEED) AND (Maybe your PCB and/or wiring isn't quite 'up-to-snuff') THEN
You may have initialization/writing problems which WILL corrupt your SD card
ENDIF

It is recommended to initialize at slower speed and switch to faster for read/writes.
Also the clock pin sucks power especially with the larger size cards.
If you are using a resistor voltage divider to convert to 3 volts use lower values to maintain signal strength.

Is code SPI(one bit at a time) or SD Bus(4 bits at a time) mode?
CRC(required for SD bus mode)?
Multiblock read and write for speed?

Norm