Panasonic write protecting SD cards

Following my purchase of a Panasonic DMC-TZ25 I noticed the problem that
access to the SD card was write only when connected to a PC via the usb
cable. Rather tiresome but it appears that Panasonic feel the need to nanny
us and not let us decide whether we wish our pictures to be protected in
this way.

Somewhat more tiresome is that the camera also sets the write protect flag
on the SD card[1] meaning that it is not possible to perform any
manipulation of card data while it is connected via an SD compliant card
reader or even re-format it for different use.

What I did notice however is that if you change to playback mode on the
camera before shutting it down then the SD write protect flag is reset and
data on the card can be modified. This also let me set a drive label for
the card so that it is easily recognised when the camera is connected.

I hope that this is of some help to others seeking a solution to the
Panasonic SD card write protect problem.


[1] a reserved SD memory location, not the physical switch

--
Peter

In article , Peter Burke says...
Following my purchase of a Panasonic DMC-TZ25 I noticed the problem that
access to the SD card was write only when connected to a PC via the usb
cable. Rather tiresome but it appears that Panasonic feel the need to nanny
us and not let us decide whether we wish our pictures to be protected in
this way.

Somewhat more tiresome is that the camera also sets the write protect flag
on the SD card[1] meaning that it is not possible to perform any
manipulation of card data while it is connected via an SD compliant card
reader or even re-format it for different use.

But this makes sense, because if you delete pictures on an SD card using
a computer you risk messing up the card and could end up later losing
data on the card.
All deletion or formatting operations (of the memory card) should be
done with the camera
--
Alfred Molon

Olympus E-series DSLRs and micro 4/3 forum at
http://tech.groups.yahoo.com/group/MyOlympus/
http://myolympus.org/ photo sharing site

In article , Alfred
Molon wrote:

Following my purchase of a Panasonic DMC-TZ25 I noticed the problem that
access to the SD card was write only when connected to a PC via the usb
cable. Rather tiresome but it appears that Panasonic feel the need to nanny
us and not let us decide whether we wish our pictures to be protected in
this way.

Somewhat more tiresome is that the camera also sets the write protect flag
on the SD card[1] meaning that it is not possible to perform any
manipulation of card data while it is connected via an SD compliant card
reader or even re-format it for different use.

But this makes sense, because if you delete pictures on an SD card using
a computer you risk messing up the card and could end up later losing
data on the card.
All deletion or formatting operations (of the memory card) should be
done with the camera

nonsense. deleting images and/or formatting in camera is a myth.

what he's describing is something else entirely, since the
write-protect on an sd card is a physical switch and not a software
setting on the card.

keep in mind that some devices ignore that switch.

In article ,
Peter Burke wrote:

Following my purchase of a Panasonic DMC-TZ25 I noticed the problem that
access to the SD card was write only when connected to a PC via the usb
cable. Rather tiresome but it appears that Panasonic feel the need to nanny
us and not let us decide whether we wish our pictures to be protected in
this way.

Somewhat more tiresome is that the camera also sets the write protect flag
on the SD card[1] meaning that it is not possible to perform any
manipulation of card data while it is connected via an SD compliant card
reader or even re-format it for different use.

What I did notice however is that if you change to playback mode on the
camera before shutting it down then the SD write protect flag is reset and
data on the card can be modified. This also let me set a drive label for
the card so that it is easily recognised when the camera is connected.

I hope that this is of some help to others seeking a solution to the
Panasonic SD card write protect problem.


[1] a reserved SD memory location, not the physical switch

Panasonic is a brand that I won't touch anymore. Everything is
off-specification at best. Most of a product's claimed technological
abilities will be incomplete or outright lies.

Is it possible that you have the write-protect switch set on the SD
card? Much like the notch in old floppy disks, that switch doesn't do
anything to the card. The card reader is supposed to check the switch
and block writes. The camera might be ignoring it.

--
I will not see posts from astraweb, theremailer, dizum, or google
because they host Usenet flooders.

Alfred Molon wrote in
:

In article , Peter Burke says...
Following my purchase of a Panasonic DMC-TZ25 I noticed the problem
that access to the SD card was write only when connected to a PC via
the usb cable. Rather tiresome but it appears that Panasonic feel the
need to nanny us and not let us decide whether we wish our pictures
to be protected in this way.

Somewhat more tiresome is that the camera also sets the write protect
flag on the SD card[1] meaning that it is not possible to perform any
manipulation of card data while it is connected via an SD compliant
card reader or even re-format it for different use.

But this makes sense, because if you delete pictures on an SD card
using a computer you risk messing up the card and could end up later
losing data on the card.

What makes you think that?

The SD card is simply a formatted data storage device (FAT32 usually) and
it doesn't care what manipulates a file as long as it does so in
accordance with the rules/specifications of the file system.

There's nothing to suggest that PCs et al can't modify the data
correctly, after all, the file systems in question were developed for
computer data storage long before they were adopted for use in cameras.

So, where does this perceived risk come from?


On a separate note, there is of course the risk of accidental deletion
but I accept that as my choice. I see no problem with this being a user
selectable option on the camera but that does not appear to be policy.

I also see no difference between the safeguards on PCs against deletion
and those on the camera. Accidentally clicking/accepting yes after seeing
'are you sure you want to delete all images/file' is equally
likely/unlikely on each and perhaps more likely outdoors, in sun, on a
little LCD display.


All deletion or formatting operations (of the memory card) should be
done with the camera

Again, why? There needs to be a justification of why this is deemed
necessary.

The camera that this one replaces had no problem with read/write access
to the mounted drive that was the SD card.

--
Peter

Kevin McMurtrie wrote in
:

In article ,
Peter Burke wrote:

Following my purchase of a Panasonic DMC-TZ25 I noticed the problem
that access to the SD card was write only when connected to a PC via
the usb cable. Rather tiresome but it appears that Panasonic feel the
need to nanny us and not let us decide whether we wish our pictures
to be protected in this way.

Somewhat more tiresome is that the camera also sets the write protect
flag on the SD card[1] meaning that it is not possible to perform any
manipulation of card data while it is connected via an SD compliant
card reader or even re-format it for different use.

[1] a reserved SD memory location, not the physical switch

Is it possible that you have the write-protect switch set on the SD
card? Much like the notch in old floppy disks, that switch doesn't do
anything to the card. The card reader is supposed to check the switch
and block writes. The camera might be ignoring it.

I did say that the actions I was referring to were related to the reserved
memory control location of the SD card and not the physical switch, that
has always been in the unlocked position.

The SD card spec allows write protection by 3 means:

1. The write protect switch

2. A temporary (editable) write protection bit within the Card Specific
Data (CSD) register

3. A permanent (non editable) write protection bit within the Card Specific
Data (CSD) register

All the symptoms in this case point to the setting of temporary write
protection flag within the CSD register by the camera when it is in
recording mode.

More worrying is that as the register based write protects cannot be
ignored it means that every pic taken results in an 'unlock'
'write' 'lock' sequence which will have a well known memory wearing effect
on the location used to store CSD register data.

Just taking pictures without this unlocking and locking has much less
effect on memory location wear as each pic will be stored in different
locations, not the same one as is the case with a register.

--
Peter

nospam wrote in
:

what he's describing is something else entirely, since the
write-protect on an sd card is a physical switch and not a software
setting on the card.

Just to be clear, I am talking about the soft write protect setting on the
card which is part of the SD card spec.

See my other reply in thread.

--
Peter

In article , Peter Burke says...

What makes you think that?

Plenty of horror stories (data loss) reported in the past here and in
other forums. It's safest to let the camera do all deletion or
formatting operations.

These problems might be attributable perhaps partially to not so good
card readers.
--
Alfred Molon

Olympus E-series DSLRs and micro 4/3 forum at
http://tech.groups.yahoo.com/group/MyOlympus/
http://myolympus.org/ photo sharing site

In article , Alfred
Molon wrote:

What makes you think that?

Plenty of horror stories (data loss) reported in the past here and in
other forums.

very few compared to the zillions of success stories.

It's safest to let the camera do all deletion or
formatting operations.

it doesn't make a difference.

These problems might be attributable perhaps partially to not so good
card readers.

more likely user error.

Alfred Molon wrote in
:

In article , Peter Burke says...

What makes you think that?

Plenty of horror stories (data loss) reported in the past here and in
other forums.

So nothing substantive then, just heresay.

Just wanted to be sure

--
Peter