How to init 4GB SD Card with RCM6700?

Question

Hi,
I have a problem when initialize 4GB SD Card using RCM6700. I use SDflash_inspect.c with some port modification and it always give me an error (-5) I/O error. My program work well on 2GB SD Card so I would like to ask is there a specific initialization for 4GB SD card? FYI I'm using 4GB SDSC card, not SDHC

thank you for your help

Answer 1

There is a limit of 2GB capacity for SD cards using Dynamic C. The full details are as follows:

Any original SD standard capacity card (i.e. not SDHC, not SDXC, nor other future SD card revisions) that meets the following requirements is expected to work with Dynamic C’s standard SDFLASH.LIB and SD_FAT.LIB functionality:

· maximum 2 GB size

· FAT16 format (FAT32 or exFAT formatted SD cards must be reformatted as FAT16)

· full support of SD’s legacy SPI communication mode

· standard 19-byte CSD format (latest functionality supports both CRC16 and CRC7 calculation check modes)