LevelX with SDCard

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New Contributor

I am looking at LevelX to use with an SD Card. I see that LevelX uses the 'spare' byes on each page.

 

It appears that the extra, say, 16 bytes on a 512 byte nominal page means there is actually 528 bytes per page. This accords with my experience with small NAND Serial Data Flash chips where I have direct access to 528 bytes per page.

 

I'm new to using SD Cards so I'm not too familiar with the spec. Are the extra bytes available to read/write? The SD Card I'm using reports 512 bytes per page. I cannot see or find any way to access the extra bytes. I'm using the i.MXRT 1064 with NXP's SDK (fsl_sd.c, fsl_sdmmc.c, etc.)

 

Or, is LevelX not advisable for SD Cards? I understand that at least some SD Cards have wear leveling built in, but I didn't think it was universal. Am I wrong in this assumption?

2 Replies
@stevenoonan, LevelX is not designed for SD cards. LevelX does use the spare bytes in NAND flash, but there is no way to access the spare bytes in SD card.

@XiuwenCai Okay, that is what I was suspecting, after making the post. Thank you for the clarification.

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