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[–] • 2 pts

Typically (not always) when the manufacturer says the max size is, say, 128GB, it means that's the largest they tested it with. For example, my phone is 32GB max microSD card. If you take a 64GB card, format it FAT32, it works fine. This isn't always the case, there are times when the OS doesn't have the facilities to calculate the necessary free space (bit width, etc) or it simply doesn't know how to handle a larger amount of space.

The times that this will not work 100% of the time is when the format of the device changes internally (SD to SDHC,) when the file system format type changes (FAT32 to exFAT,) or when the amount of space on the card exceeds the bit width that the OS can calculate, although this hasn't really been an issue since the 32-bit limit was removed on hard drives.

That's not an exhaustive list, but if you can format the card to the proper file system and it's the same type of internal makeup, it should work.

[–] • 1 pt
[–] • 1 pt

I confess it's been a long time since I've messed with FAT clusters, but generally, that statement is correct - the larger the drive space, the larger the FAT clusters have to be. 64K is the largest that FAT32 really supports with any kind of usefulness. I seem to remember that FAT32 gets very fussy once you get past 200GB, and tools out there won't format things larger than this. I believe the spec doesn't go beyond that, but don't quote me there. exFAT was created to solve this issue for flash drives, and NTFS for hard drives. You can format flash to NTFS but as it's journaling system, you wear your flash out quicker with journal and information writes.

If you're not using GNU/Linux, there's a tool for Windows (which refuses to format things larger than 32GB as FAT32) that can format for you. It's called fat32format and you can get it here: http://www.ridgecrop.demon.co.uk/index.htm?fat32format.htm

It's one of the tools that I keep in my arsenal.

[–] • 1 pt (edited )

Nah I use linux... And I have to format the thing to fat32 for those machines (which run a linux based distro too, raspi style https://wiki.dingoonity.org/index.php?title=OpenDingux:About )... Not sure if linux does the job as well as windows when it comes to fat32 formatting btw

[–] [deleted] • 2 pts

After searching around the little bit, it seems like the only drawback to using a larger sized microSD card is some slower memory access times. If the data clusters are formatted appropriately for the total storage size of the card, it may not have an impact on the performance as much. Given that cartridge games probably didn't have the bandwidth available today and that card storage massively trumps disc-based read times, I doubt there would be a large issue if the times were a few milliseconds slower/sub-optimal. Most of the posts I found also mentioned they were using a 256GB sized microSD card.

[–] • 1 pt

Thx

In the comment I've found this

>Allocation unit sizing to set when using the fat32 formatting tool. The recommended cluster size to set for a 16GB FAT32 partition is 4KB, the recommended cluster size for a 64GB FAT32 partition is 16KB, the recommended cluster size for a 128GB FAT32 partition is 32KB and the recommended cluster size for a 256GB partition is 64KB. Furthermore, you cannot increase the cluster size beyond 64KB because this would cause certain programs to calculate disk space incorrectly. Note that some versions of Windows prior to Windows XP, including the old Windows 95 and Windows 98, don't support cluster sizes above 32KB

So it means that it's not possible to properly go beyond 256gb with fat32 without getting "sloppy", because of max cluster size

But technically it seems possible though

What's the problem of going for let's say a 512gb disk, with 64kb cluster size? I mean the real problem, like one that breaks the card or make read/write errors happen. Does it just lower data transfer rate or is there more or something else to ponder when going that way?

[–] [deleted] • 1 pt

>I mean the real problem, like one that breaks the card or make read/write errors happen. Does it just lower data transfer rate or is there more or something else to ponder when going that way?

I was thinking it may have to do with the reader module and voltage/current or something like that. However, the Wikipedia article on the format doesn't seem to indicate anything that raises a red flag on voltage/current draw with higher card capacity. The actual card storage size and storage size calculations imposed by the format also seem firmly established (from like, back in 2006), so that doesn't seem to be it either. I'm tapped out, so it's probably as is saying that it's only related to manufacturer testing and what they can guarantee from that info.