Question Reducing the effective capacity of a microSD card ?

[Pimpom]

I have a project using a DFPlayer module which supports microSD cards of up to 32GB. I may want to build more than one unit but 32GB cards are becoming scarce these days. Heck, some versions of the project will use less than 1MB of space.

I read somewhere - I've forgotten where - that it's just a matter of making a 32GB partition on a larger capacity card, but at the moment I don't have any spare card i can test this with. Can anyone please confirm this? That is, will a device that can recognise a limited storage capacity be able to use a larger one reduced in effective capacity by partitioning it?

 

[Grobe]

Well, this means your DFPlayer module probably supports SDHC (Secure Digital High Capacity) cards, while the larger SD cards are SDXC (Secure Digital Extended Capacity) but doesn'y support SDXC cards.

It says in more details here:
https://www.flashtrend.com.au/blog/our-blog/whats-the-difference-between-sdxc-and-sdhc

 

[USAFRet]

Can it utilize the FAT32 file system?
If so, reformat it to FAT32.
That will be a 32GB partition.

 

[Pimpom]

Thanks for the replies. Yes, it can use FAT16 and FAT32. But if it cannot use SDXC, will formatting it to FAT32 and having a 32GB partition do any good?

 

[USAFRet]

Thanks for the replies. Yes, it can use FAT16 and FAT32. But if it cannot use SDXC, will formatting it to FAT32 and having a 32GB partition do any good?

FAT32 will show not just a single partition, but the entire drive capacity as 32GB.

Try it. See what happens.

 

[USAFRet]

Or, just buy a stack of 32GB cards now.
Stock up.
https://www.amazon.com/PNY-Elite-microSDHC-Memory-P-SDU32GU185GW-GE/dp/B09WW69YRD

 

[Pimpom]

FAT32 will show not just a single partition, but the entire drive capacity as 32GB.

Try it. See what happens.

As I said at the beginning, I don't have any spare card I can use to try out. I live in a remote place and there are no good sources in my town. An online order will take at least a week to get here. That's why I decided to ask here.

And since, according to Grobe's link, SDXC cards are not backwards compatible with SDHC devices, I don't see how just reducing the apparent size will make it compatible.

 

[Pimpom]

Or, just buy a stack of 32GB cards now.
Stock up.
https://www.amazon.com/PNY-Elite-microSDHC-Memory-P-SDU32GU185GW-GE/dp/B09WW69YRD

US$15 (equivalent) each for a 32GB card? No way. I can get a 256GB model for that. This is not an emergency.

Edit: Oh, I see that the link automatically went to my country's Amazon site. The US price is more reasonable but of no use for me.

 

[USAFRet]

US$15 (equivalent) each for a 32GB card? No way. I can get a 256GB model for that. This is not an emergency.

Your market may be different, but that is a 5 pack for $20.
$4 each.

But do try the FAT32 concept.

 

[Pimpom]

Please see the edit to my post just before you last one.

Going to bed. It's 3:30 am here.

 

[USAFRet]

Please see the edit to my post just before you last one.

Ah....sorry.

But still, 32GB microSD cards still exist, and are not rare.

 

[Misgar]

If you're expecting a FAT32 format will limit the capacity of a high capacity SDXC card to 32GB, that might not be true if you use a third-party formatter.

I use FAT32Format on much larger drives, e.g. 500GB hard disk for a TV. For some reason it needed to be FAT32, not exFAT.

http://ridgecrop.co.uk/index.htm?fat32format.htm