I thought about posting this in the mobile development section, but hey it's more a general question and many of us have Android devices, and may have faced this problem.

I have happily been using 64gb SD / microSD cards on my PC and cameras for a while now, no problems. Now I have a few Android devices that I have tried this on, but I can't seem to get anything over 32 gb cards to work with my android devices. :angry:

I gather the 'problem' comes because up to 32gb (SDHC), the cards come formatted as FAT32, whereas above that (SDXC), they come formatted as exFAT, which Microsoft seems to own, so maybe hardware makers / OS providers have to pay Microsoft to have exFAT support? :mellow:

So after a bit of research online I read about using 3rd party programs to format the larger SD cards with FAT32 on a PC, with the idea that they should now read and work on both devices:

http://www.androidauthority.com/high-capacity-microsd-cards-android-gary-explains-690710/

http://gearnuke.com/use-64gb-bigger-microsd-cards-android-device-maxes-32gb/

However while the 64gb sd cards now 'appear' on the android devices, some of the files are missing, or maybe don't play.. The support seems to be broken, it is like only half the file system is being recognised, there doesn't seem any rhyme or reason as to whether some files work and some don't.

So I have 2 questions:

1. Has anyone managed to get >32 gb cards to work PROPERLY with android (especially with FAT32)? If so, how? Why, (if FAT32 can handle more than 32GB), does Android not handle this properly?
2. If this is not just me (and I don't think it is), what were the SD card standards people thinking? Could they not have standardized on something that was not patented and controlled? Surely it isn't rocket science to come up with an open file system?

I'm not usually one for conspiracy theories, but I have to say, this smacks of one. It may be that certain manufacturers are able to pay the exFAT 'tax', or cross licence patents, while others (on smaller margins) cannot. Whereas this whole situation could have been avoided by using an open file system standard. I would really love to hear that there are in fact valid tech reasons why the 32gb limit is somehow 'magic', and that there are no underhand dealings going on. :unsure:

The situation is even more dubious than that, because Google really don't want you to be using SD cards, so you are forced to store everything in the 'cloud' and pay them money and have them sift through your data (to target you with ads), so I wouldn't put it past them to purposefully sabotage SD card support in Android (they seem to go as far as leaving out SD card slots on their models to make this decision for you).

Google really don't want you to be using SD cards

I doubt that is it.

It may be that certain manufacturers are able to pay the exFAT 'tax'

Now you're getting closer...

Fat32 as a volume size limit of 32GB on Windows and many portable devices like phones and cameras. There are some tricks that some tools can use to make it bigger. There is a limit of about 4 million clusters on a drive and they can use a larger cluster size. It comes with a high risk since many devices won't recognize the cluster size. If you use one of those tricks then stick it in your phone, there is a chance it will corrupt data as it writes.

exFAT has a restrictive license, but allows for petabytes of storage space. But as you mention, it has a patent licensing cost.

The support seems to be broken, it is like only half the file system is being recognised

Now we get to the issue. The protocol for the hardware.

There are several versions of the standards. The ones that matter here are:

* Original SD protocol, which works up to 2 GB.

* High Capacity SD protocol, which works up to 32GB. SDHC for short.

* Extended Capacity protocol, which works up to 2TB. SDXC for short.

If your phone's hardware only speaks the original SD protocol then it is really old, but it won't work with SDHC or SDXC cards. You'll need a newer device that supports it.

If your phone's hardware speaks both the SD and SDHC protocol you can use cards up to 32GB, but you won't be able to use SDXC cards. You'll need a newer device that supports SDXC.

The two mix together for compound problem. No SDXC support plus no exFAT support means it won't work. No SDXC support with exFAT support also won't work, requires a hardware upgrade. SDXC support with no exFAT support won't work, requiring either non-standard file system or updated software. SDXC support with exFAT support works great.

It seems that commands that reference the addresses above 32GB are failing, meaning your hardware needs an upgrade to use.

That means it isn't Google or Microsoft that are your problem. The next generation of hardware protocols have replaced the previous.

Now that is interesting .. I've read a few places suggesting there weren't any hardware differences between the SDHC and SDXC slots, and assumed it was a software matter for talking to the card, but I really don't know anything about the hardware side.

The 'newer' 'older' argument : I have an old cheap media player (5 years old) that worked fine with 64gb cards, recently bought a nexbox a95x, and an updated newer version of the original media player, and neither of the new media players work with 64gb. :(

It would seem ridiculous that newly manufactured devices are purposefully crippled to SDHC sockets in terms of hardware given the backwards compatibility .. unless the hardware is also patented. :blink:

I had also since read various things suggesting there may be some kind of 32 gb limit for FAT32, so it does seem that it is feasible that as you say, above that there is no 'standard' so things may or may not work.

It seems there was a few apps in the play store that enabled exFAT support, but won't work in later version of Android because of security 'enhancements':

https://play.google.com/store/apps/details?id=com.paragon.mounter&hl=en_GB

I have to go away for a few days, but the alternative is to see if I can build android from source for the nexbox, and include the exFAT support, and seeing if there is any joy. It just seems ridiculous that I have lots of 64gb cards, but can't use them unless I format them as 32gb... :rolleyes: