can microSD be write protected?

[Talal Itani]

Hello,

Is there a way to write-protect microSD flash cards? There is no mechanical
switch on the little card. Can it be done by software?

Thanks
T.I.

 

[John B]

Hello,

Is there a way to write-protect microSD flash cards? There is no
mechanical switch on the little card. Can it be done by software?

Thanks
T.I.

Yes. Code a 'WriteDataToProtectedCard()' function and comment out the
line that sends the data to the card. Then if you wish to have the card
write protected call that function instead of the normal one.

It should work quite well.

 

[Talal Itani]

Hi John,

Thanks, but this is not what I meant. I want to program the microSD chip,
and then keep others from re-programming it. Similar to the write-protect
bit in windows files.

T.I.

 

[Henry Kiefer]

| Hello,
|
| Is there a way to write-protect microSD flash cards? There is no mechanical
| switch on the little card. Can it be done by software?

The mechanical switch is read by the host (or not) located on the card interface slot. Inside the SD card the mechanical switch does
nothing.
So you can write to the card even if it is "write-protected".
Some slots do not have a micro-switch! Some SD cards don't have a mechanical switch - better say "slider".

- Henry

 

[[email protected]]

Hello,

Is there a way to write-protect microSD flash cards? There is no mechanical
switch on the little card. Can it be done by software?

Thanks
T.I.

Even full sized SD card don't have write-protect. The write protect
mechanical switch on a regular SD card does nothing at all. The host/
OS/card reader detects its position and decides on weather to use or
ignore it. Boot into a system that ignores it, like a modified version
of Linux for example, and you can easily format a write protected SD
card.

 

[Talal Itani]

This is unfortunate. I was hoping I can set a bit, somewhere inside the
microSD, and have the data secured, and protected from further writes.

 

[Iwo Mergler]

This is unfortunate. I was hoping I can set a bit, somewhere inside the
microSD, and have the data secured, and protected from further writes.

I vaguely remember an announcement about some antifuse 'camera' memory.
It was an outfit called "matrix semiconductors" or similar.

That would be write-once.

Kind regards,

Iwo