Does SL-C860 support MMC?

[TonyOlsen]

Last week I bought a new 1 GB MMC card (I chose MMC over SD because I don't support the DRM SD movement).

I put the MMC card in my wife's camera and it recognized the whole 1 GB (I was pleasantly surprised since she had an "older" camera.  When her camera hooked up to my windows (yeah, I know   ) desktop, windows recognized the 1 GB as well.  I formatted it with Fat32 and did a simple scandisk.  All seemed well...

I then put the MMC card in my SD card slot in my SL-C860 and the Zaurus recognized without trouble.

But then odd things started to happen.  I wasn't able to write to the card.  Sometimes Linux had trouble ejecting the card.  I thought that perhaps the card's fat table was corrupted (since my desktop DID crash while I attempting to surface scan the card).

I tried:

bash-2.05$ mkdosfs /mnt/card
mkdosfs 2.8 (28 Feb 2001)
mkdosfs: unable to open /mnt/card

I can't find the SD card (nor the CF card) under /dev/hd... anywhere

Any ideas?

Does the SL-C860 support MMC cards?  How do you format SD/MMC cards in your Zaurus terminal?

MMC Specs:
My Flash
Multi Media Card
1 GB PC Data
0408AD6

Thanks in advance...

[sigmaX]

Hi !  I dont know if zaurus support MMC format, but I had same problem with an SD card ... I tried to get it back in track formatting it again under windows, but it kept being unrecognized by the zaurus. I thought I lost the SD !! Now: I asked for a friend's digital camera which used mmc / SD and I formatted it again in there.

Problem fixed.

Formatting under windows= doesn't work
Formatting under HP digital camera= Fixed it again

Regards,

Enrique.

[PsionX]

I have a MMC card since 6 months, no problem.... It's a 64Mb, only !!  
(Fat 16 formatted on XP pc / C750 / Cacko 1.21b)

[lardman]

I've also had an MMC card for a long while - 128MB from Crucial.

I'd never had troubles with it until I used pdaXrom, then I used to get those IO errors people were talking about. Flashed back to OZ and it was fine; I've no idea why. It's now in use in my digital camera as I bought a larger SD (cheaper than MMC).

You might try updating your fdisk package on your Z (I do all my disk manipulation on my Zs, I don't even own a card reader :-), there's a recent thread about a new version being tested.


Si

[TonyOlsen]

More tests and update:

Code: [Select]

bash-2.05$ fsck.vfat /mnt/card
dosfsck 2.8, 28 Feb 2001, FAT32, LFN
Read 512 bytes at 0:Is a directory
bash-2.05$ fsck.msdos /mnt/card
dosfsck 2.8, 28 Feb 2001, FAT32, LFN
Read 512 bytes at 0:Is a directorybash-2.05$
I formated the card via my cheap HP Digital Camera connected to my Windows laptop via USB.  I formated it as FAT (FAT16), but fsck says its FAT32.  Why?

...should I format the card as Fat32 instead?  Is that better?

I couldn't ever get mkdosfs working...

Code: [Select]

bash-2.05$ mkdosfs /mnt/card
mkdosfs 2.8 (28 Feb 2001)
mkdosfs: unable to open /mnt/card
While the MMC card is hooked up to my desktop (via the USB camera), I did some tests.  I moved 3 movies to the card and they all played back fine.  In fact, these moveis even play back fine in the Zaurus.

It appears that the Zaurus can read from the card just fine... it just can't write to it.

Also, if I disconnect the card from the Windows machine without first "eject"-ing it via the Windows menu (ie. I turn of the HP USB Camera, remove the MMC card, unplug the camera, etc) the card is in a state of limbo.  Zaurus doesn't see anything on the card.  ...but if I plug the card back into Windows and then go through the "eject" procedure, then the card shows up in the Zaurus.  This odd behavior appears to be Windows-centric and is consistant with my CF cards as well (my Ricoh digital camera can't my CF card if I don't eject it from Windows correctly).

So... why can I write to the card?  Is it a hardware limitation?  Does the Zaurus support 1 GB MMC cards?  (If thought all SD ports are backwards compatible with MMC) How can I format the card from the Zaurus?

[lardman]

I couldn't ever get mkdosfs working...

Possibly because you're using it wrongly, my apologies for not spotting this earlier:

# umount /mnt/card
# mkdosfs /dev/mmcda1
# mount /mnt/card

I formated it as FAT (FAT16), but fsck says its FAT32. Why?

There's a setting which says what the partition is supposed to be. This is set using fdisk. Have you tried this?


Si

[TonyOlsen]

You might try updating your fdisk package on your Z (I do all my disk manipulation on my Zs, I don't even own a card reader :-), there's a recent thread about a new version being tested.

Tell me more...  I've used MS DOS fdisk, but I never used it in Linux.

There's a setting which says what the partition is supposed to be. This is set using fdisk. Have you tried this?

Hm...fdisk... a new toy for me to play with.  Thanks.       I'll try formating it within the Zaurus and see how that works.  

Thanks!  

[TonyOlsen]

Code: [Select]

bash-2.05$ cd /dev/mmcda1
bash: cd: /dev/mmcda1: Not a directory
bash-2.05$ su
# umount /mnt/card
# mkdosfs /dev/mmcda1
mkdosfs 2.8 (28 Feb 2001)
# mount /mnt/card
# exit
Hm... I guess /dev/mmcda1 is only available when the drive isn't mounted.  Insteresting.  

The format worked.

Code: [Select]

bash-2.05$ fdisk
bash: fdisk: command not found
bash-2.05$ fdisk -?
bash: fdisk: command not found
...but it couldn't find fdisk.  I thought fdisk was only a DOS command... I've never seen it in Linux before...

Code: [Select]

bash-2.05$ cd /mnt/card
bash-2.05$ ls
bash-2.05$ mkdir test
mkdir: Cannot create directory `test': Permission denied
bash-2.05$ su
# mkdir test
# ls
# ls -l
#                  
...also, I was able to copy all of my stuff off of the MMC card, but I'm still not able to write to it...

This is really wierd...

Code: [Select]

# fsck.msdos /mnt/card
dosfsck 2.8, 28 Feb 2001, FAT32, LFN
Read 512 bytes at 0:Is a directory
# fsck.msdos /dev/mmcda1
dosfsck 2.8, 28 Feb 2001, FAT32, LFN
Got 126464 bytes instead of 126832 at 512
# fsck.msdos /dev/mmcda1 -v
dosfsck 2.8 (28 Feb 2001)
dosfsck 2.8, 28 Feb 2001, FAT32, LFN
Read 512 bytes at 0:Input/output error
#      
If I'm reading this correctly, fsck is failing because of an I/O error where it is getting a different number of bytes than what it is expecting...

Any ideas?

[lardman]

Hm... I guess /dev/mmcda1 is only available when the drive isn't mounted.

It's not a directory per se (it's a device), so you can't 'cd' to it. If you'd tried 'ls /dev/mmcda*' you'd have seen it.

Have a go with fdisk, remove all of the current partitions and create a new one.

Take a look at the HowTos here about formatting, there are a couple which should give you an idea of how to use fdisk: http://www.zaurususergroup.com/modules.php...&pagename=Other

Take a look in this thread to get a new version of fdisk which is supposed to work better with large cards: https://www.oesf.org/forums/inde...c=6520&hl=fdisk

Let us know how you get on.


Si

P.S. An older version of fdisk can be obtained from here: http://docs.zaurus.com/downloads/fdisk_2.11g-4_2_arm.ipk

[TonyOlsen]

I downloaded the older fdisk, you linked above, and tried using it.  The fdisk was able to repartition the unmounted SD disk any way I could think of (and many ways I never knew were possible: I didn't know there were that many different versions of the FAT16 format).  The changes were saved to the card, and the card reflected the changes... but the Zaurus still couldn't write to the card.  In fact, most applications that attempted to write to the card ended up waiting forever (and essentially freezing up the application).  It is interesting that the Zaurus doesn't appear to have any problems reading data from it and/or changing the partitions.

Does that imply that the partitions/format itself are/were setup incorrectly?

I'll try using the new fdisk from the thread you linked above and I'll let you know how that goes.

(Thanks for the help so far    )

[lardman]

(Thanks for the help so far :-) )

No worries, always glad to help :-)

Does that imply that the partitions/format itself are/were setup incorrectly?

I'll try using the new fdisk from the thread you linked above and I'll let you know how that goes.

No idea, but I think using the new fdisk is a good idea. If that fails then back to the drawing board.


Si

[TonyOlsen]

FYI: This thread has picked up in the fdisk thread recommended above:

new fdisk thread

[Martin]

Hi everyone

... I have same problems using my two 64 MB + one 512 MB MMC and :-(( ...

... and the solutions is as easy as ... for some card you have to use /dev/mmcda not /dev/mmcda1 ... don't ask me why ... I have a problem very near to this with my (blue) 8in1 hama usb cardreader ... the slot do not use /dev/sda1 /dev/sda2 ... they use /dev/sda, /dev/sdb1, ... really not sure WHY? It depends on inserted cards ... maybe something to do with device which could be split up with 2 or more partitions ... and others not ?! same with my cardreader ...

... use manual mount command or edit /etc/fstab :-)

Anybody an idea why this?

Martin

[kopsis]

... and the solutions is as easy as ... for some card you have to use /dev/mmcda not /dev/mmcda1 ... don't ask me why ...

The why is because in some cases you'll find cards formatted without a partition table. Running without a partition table is the norm for floppies but rare on other media. However, there are a few brain damaged devices that will format MMC cards "floppy style" with no partition table. I ran into this same thing a few years back with small capacity CF cards. I found a few that actually came from the manufacturer with a no-partition-table format!

[TonyOlsen]

Ok, then it sounds like that doesn't solve my problem.

In the meantime I'll go ahead and use it as a read-only memory card for the many things I carry around but don't change.

The card has passed all read-only test (including playing movies, etc), so this should hopefully work... =)

How do you make an MMC card read only?  Do you simple do a chmod on the /mnt/card (or the directory this points to)?  Do I need to change the fstab file?  How?