# Sandisk SDHC troubles

## CaptainBlood

At mmc insert, system logs

```
mmc0: cannot verify signal voltage switch

mmc0: new ultra high speed SDR104 SDHC card at address 0007

mmcblk0: mmc0:0007 SL16G 14.4 GiB 

mmcblk0: p1

mmcblk0: unknown error -22 sending read/write command, card status 0x900

mmc0: cannot verify signal voltage switch

mmc0: tried to reset card

mmcblk0: unknown error -22 sending read/write command, card status 0x900

blk_update_request: 1 callbacks suppressed

blk_update_request: I/O error, dev mmcblk0, sector 8984

blk_update_request: I/O error, dev mmcblk0, sector 8992

blk_update_request: I/O error, dev mmcblk0, sector 9000

blk_update_request: I/O error, dev mmcblk0, sector 9008

blk_update_request: I/O error, dev mmcblk0, sector 9016

blk_update_request: I/O error, dev mmcblk0, sector 9024

blk_update_request: I/O error, dev mmcblk0, sector 9032

blk_update_request: I/O error, dev mmcblk0, sector 9040

blk_update_request: I/O error, dev mmcblk0, sector 9048

mmcblk0: unknown error -22 sending read/write command, card status 0x900
```

mmc gets rarely automounted.

storage media is new.

Any idea what to do?

Thks 4 ur attention.

----------

## NeddySeagoon

CaptainBlood,

Not all card readers are equal.  Not all cards are equal either.

Over the years, as memory cards have got bigger, standards have changed, so old hardware knows nothing of new standards.

```
mmc0: new ultra high speed SDR104 SDHC card at address 0007

mmcblk0: mmc0:0007 SL16G 14.4 GiB

mmcblk0: p1

mmcblk0: unknown error -22 sending read/write command, card status 0x900

mmc0: cannot verify signal voltage switch 
```

suggets the reader and card are not compatible.

It looks like the kernel driver is trying to determine the voltages it should use on the data/address signal lines and either the card or reader does not know how to do that.

Have you used ultra high speed (SDXC) cards with that reader?

Can you try the card in another reader?

----------

## CaptainBlood

I've thrown the the hardware package away.

Nevertheless seems to be a

```
SanDisk microSDHC Ultra 16 Gb UHS-1
```

Because I like lean kernel configs, I had to update it to get the device working.

I've just successfully tried the new device with my old HTC Wildfire which is 4 to 5 years old. Doing so allowed me to insure it hasn't be bricked for what ever reason.

The initial mobile phone SD card has successfully been mounted on gentoo at first attempt.

Nevertheless in pretty sure data stored in the new SD card have been copied via gentoo,

And I'm 100% sure device got mounted for a while after a few trials @ kernel settings.

Old SD card returns

```
Jan 30 17:10:03 n kernel: mmc0: new high speed SDHC card at address 0001

mmcblk0: mmc0:0001 00000 14.7 GiB 

mmcblk0: p1

FAT-fs (mmcblk0p1): Volume was not properly unmounted. Some data may be corrupt. Please run fsck.

udisksd[2218]: Mounted /dev/mmcblk0p1 at /run/media/luc/7984-090D on behalf of uid 1000
```

Thks 4 ur attention, interest & support

----------

## NeddySeagoon

CaptainBlood,

That's two different generations of cards.

The old one is

```
Jan 30 17:10:03 n kernel: mmc0: new high speed SDHC card at address 0001
```

The new one is 

```
mmc0: new ultra high speed SDR104 SDHC card at address 0007
```

Notice the "ultra" snuck in there.

They are supposed to be backwards compatible, with the emphasis on "supposed to be".

The idea is that ultra high speed cards can operate at the old speeds and voltages and signalling methods if needed.

----------

## CaptainBlood

Hi,

It just so happend new sd card got automounted in lxde @ boot.

Any tip what and where to grab information that could help to troubleshoot this issue?

Thks 4 ur attention, interest & support

----------

## erg_samowzbudnik

I see it's an old thread,

I have the exact same issue with a new SDHC card from Sandisk.

It mounted without issues the first time, formated and made filesystems, copied files, booted raspberry pi with it fine.

Now when I put the card into my gentoo laptop it's not recognised anymore. It isn't recognised on Ubuntu machine either. It is recognised on Windows 10, I can format it and make filesystems just fine.

It runs on the raspberry pi too.

When I formated it with windows the first time I could see it again from gentoo, make filesystems and copy files. After I formatted it with windows for the second time I cannot do it anymore.

This is the only error message I see:

```
mmc0: cannot verify signal voltage switch

[ 5054.210538] mmc0: error -110 whilst initialising SD card
```

I have a good few years old laptop so I guess it's reader/card incompatibility, it is a suspicious card though: bought it as 64G, has 64G printed on it, is in fact 128G. Tested read/write speed and it's ok, system on raspberry pi boots fine. Packaging looks legitimate so does the card.

Is there any hope I can get the old card reader working with it or do I have to buy a new sd card reader?

Is there a way to try and debug what goes awry?

----------

