Strange issue with memory cards

[VascoFerraz]

Hi,

I've been testing some memory devices I own:
- 2x Kingston SD 8GB class 4 using chinese usb adapter -> Random problems
- 1x PNY SD 8GB class 4 using chinese usb adapter -> Random problems
- 1x Nokia MMC 256MB using Nokia usb adapter -> Random problems
- 1x Lexar USB Pen 64GB -> No problem

... and I am experience randomly errors but only on SD and MMC cards. Sometimes I don't get errors at all.
The Lexar Pen works with no errors.

The Rpi is a Model B Revision 2.0

Code: Select all

[    6.673861] sd 1:0:0:0: [sda] 501760 512-byte logical blocks: (.....
[    6.768515] sd 1:0:0:0: [sda] Write Protect is off
[    6.780116] sd 1:0:0:0: [sda] Mode Sense: 03 00 00 00
[    6.809667] sd 1:0:0:0: [sda] No Caching mode page found
[    6.821741] sd 1:0:0:0: [sda] Assuming drive cache: write through
[    6.916417]  sda: sda1
[    6.932574] sd 1:0:0:0: [sda] Attached SCSI removable disk

Any idea what's going on?

Thanks

Vasco

[VascoFerraz]

bump

[ShiftPlusOne]

What errors are you seeing?

[VascoFerraz]

These messages are marked in red and randomly appears in dmesg.

Sometimes the SD card is recognized after that message and sometimes it is not recognized.

Code: Select all

[    6.809667] sd 1:0:0:0: [sda] No Caching mode page found
[    6.821741] sd 1:0:0:0: [sda] Assuming drive cache: write through

[ShiftPlusOne]

Those look normal to me. They shouldn't appear randomly though, only each time the device is connected. Otherwise, there may be a bad connection somewhere.

[VascoFerraz]

Maybe you're right.

The old MMC (with an original Nokia Adapter) only throws that message at boot.
The new ones - SD 8GB (using a chinese adapter) throws randomly those messages while the Rpi is running.

So, maybe the Chinese adapters are bad quality!

I have an external memory card reader... not a chinese one... so I'll try again those SD 8GB with that reader.

[VascoFerraz]

Sorry for the late reply but I am almost sure that this is a power problem.

That is, the same SD works flawless in an RPi3 with the official power supply.

In an RPi1, with a Asus Nexus 7 charger, (I guess it's a 2.0A) throws those error messages.

I am clueless but I point for lack of power on the RPi1 or a defective (or bad quality) power supply. However, it's an Asus power supply... So, again, clueless!

[HawaiianPi]

...I am clueless but I point for lack of power on the RPi1 or a defective (or bad quality) power supply. However, it's an Asus power supply... So, again, clueless!

Try your Pi3 power supply with your Pi1, and if the problem goes away then you know it was power.

Note that phone/tablet battery charging is much less sensitive to voltage fluctuations than a computer is. I have tested "5V/2.4A" chargers that dipped down to 4.5V at only 1A. That will still charge your device, but it's well below what is recommended for the Raspberry Pi computer.

[VascoFerraz]

I am almost sure that the problem is related to the USB/SD chinese adapter.
I have 4 USB/SD chinese adapters and two of them randomly throw these errors.