SD/TF Card handling and card size UMI Z - SOLVED

mickey

I inserted a brand new Sandisk Extreme Pro SDXC 64 GB to my brand new UMI Z before it was started the first time. The phone recognized the card.
While formating for using as an external storage a message told me that there are issues and the procedure stopped.
To verify the card i put into a windows maschine and reformated it with the default filesystem exFAT. The card worked perfectelly for that windows computer.
I reinserted it into the UMI Z but since the first fail attempt that Card has never been recognized again. I tried several filesystems and partition id´s with no success.
Then i put exactelly these card into my Amazon Fire TV and after beeing formatet by Fire TV it worked fine in that Box.
I put the 32 GB Card,  which i took off from Fire TV, to UMI Z and ..... it worked fine.

Then i exchanged the cards again, both are working now ............. i put 32 GB back to Fire TV and my brand new 64 GB sandisk back to UMI Z and again,
the UMI Z does not recognice that a card is inserted. Both had been formatet by Fire TV with FAT32 (0x0C Partition Id).
I tried the 64 GB also in a Samsung Tab 3 and it was regonized correctelly and could be formated without any issues.

An App which i loaded from playstore named "SD Insight" showed me these results
32 GB : Detected, Size 31 GB, Bus Location mmc1:0007, Device /dev/block/mmcblk1,  found 1 Partition 31 GB
64 GB: Detected, Size 31 GB, Bus Location mmc0:0001, Device /dev/block/mmcblk0,  found .. crazy ... 30 Partitions different sizes

It seems that UMI Z cannot handle that 64 GB SDXC (although the specification says up to 256 GB) and ...
It seems that a card once has failed is remembered as broken and could not be reformated in the device.

Does anyone have same or equal experiances and is there a way to force "redetection" of an sd card ?

Many thanks in advance
Michael

MarcinP

Hi
Please perform factory reset on your device (settings - backup and reset - factory data reset) .
Then try again with SD card.
Also check for updates.

mickey

i did already but without any positive result. I checked with another app called "Drive Info" and it shows me unmounted partitions for MMC internal storage. Could it be, that i pressed the wrong button (sd for internal storage) by accident instead of using for external storage and the failing format procedure caused that many partitions and mountpoints which are bound to exactelly that physical card?

mickey

i found some more facts. The App shows me always that a MMC card with 31 GB is present, even if my 64GB SanDisk is not inserted. When i use the 32 GB card, it shows the SanDisk MMC and i can select the 31 GB SD as well. Could it be that UMI uses a built in SanDisk MMC for internal storage?

bencebacsi

Hi,
/dev/block/mmcblk0 represents the internal memory, not your memory card. The SD Insight simply works bad and even in my test phone, that contains a 64GB Samsung Evo SDXC card, you can access the internal memory as a "SanDisk mmc card" So please just forget about that app.
Unfortunately, MTK systems still cannot handle the exFAT file system (that's licensed by Microsoft), so please format your card to FAT32 in Windows or just format it with your phone. If the phone fails at formatting your card, it might be a fake memory card. Please share the link of the place of purchase of your SD card. There are some tools for testing the real capacity of memory cards but they're not always reliable. I suggest you to copy data to your card that fills more than half of its capacity, then try to read back all the copied data. If your card is a fake one, probably all folders will be copied but not all files.

Russj

Hello -
     I'm having some SD card problems too... I have tried several reputable brands. The latest is a PNY 32gb card.. inserted it, the phone recognized it and formatted it for me. But the native file manager app doesn't see the card, just the main storage. If I go to the System settings and open Storage and USB, the PNY card shows up but I still can't access it. I have rebooted the phone... nothing changes. I still can't access the PNY card.

Daphone

I have no such problems wit the 128Gb Toshiba Exceria i use ( 2016 class 10 / U3 version )
http://www.toshiba-memory.com/cm ... ia-pro-m302-ec.html

I have had it in and out of the phone several times as transferring filed to the card in the phone ( or the phones own build in storage for that metter) are really slow ( phone connected to USB 3.0 plug on the back header of my motherbord )

But in the USB 3.0 card reader i can transfer files as fast as the cards 40 /90 MB/s write / read speeds allow, but in the phone its like its USB 1 at best.

But my Z handle the SD card just fine when i put it back in the phone.

bencebacsi

Russj replied at 2017-4-26 05:05
Hello -
     I'm having some SD card problems too... I have tried several reputable brands. The late ...

Hi,
If your SD card is pre-formatted to exFAT file system, then any smartphone with MediaTek processor cannot handle it. Please format it to FAT32 under Windows (in a card reader), then it will work properly in your phone if it's a genuine SD card.