SD/MMC cards, a year later (2010)

Re:SD/MMC cards, a year later (2010) by dale_glass on Wednesday August 14, 2024 @05:28AM (#41244242)

I've heard of this, but there seems to be a lack of practical information. If this is true, then:

* Shouldn't SD cards have an expiration date? What if you buy a card that's been sitting on the shelf for a year?

* What is the proper maintenance procedure? Like should I let it sit in the reader for an a minute, 15 minutes, an hour for the controller do its magic?

* Are the translation tables better protected? Does the card return to full working order when reformatted?

* Are there testing tools for this? I remember CDs had tools that could tell you how much error correction the drive had to do.

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Re:SD/MMC cards, a year later (2010) by userbinator on Thursday August 15, 2024 @08:32PM (#41261934)

Shouldn't SD cards have an expiration date? What if you buy a card that's been sitting on the shelf for a year?

If the flash was blank at manufacturing, it would remain blank after a year as there would be no charge to leak out. The problem is when the controller also stores its firmware on the main NAND, but AFAIK that isn't the case for SD cards (which have very little in the way of firmware compared to SSDs.)

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Re:SD/MMC cards, a year later (2010) by dale_glass on Friday August 16, 2024 @04:28AM (#41264389)

They're not sold blank though. They have a partition table and FAT32/exFAT filesystem on them.

And I'm pretty sure even SD cards have a translation layer.

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