SDMJ-32 SanDisk, SDMJ-32 Datasheet - Page 48

• Manufacturer Part Number: SDMJ-32
• Manufacturer: SanDisk
• Type: MultiMedia Cardr

Specifications of SDMJ-32

• Density: 32MByte
• Operating Supply Voltage (typ): 3.3V
• Operating Temperature (min): -25C
• Operating Temperature (max): 85C
• Package Type: MMC
• Mounting: Socket
• Pin Count: 7
• Operating Temperature Classification: Commercial
• Operating Supply Voltage (min): 2.7V
• Operating Supply Voltage (max): 3.6V
• Programmable: Yes
• Lead Free Status / RoHS Status: Compliant

Revision 1.3
© 2005 SanDisk Corporation
The sequence for unlocking a card is as follows:
If the PWD content equals to the sent password then the card will be unlocked and the
card-locked status bit will be cleared in the status register. If the password is not correct
then the LOCK_UNLOCK_FAILED error bit will be set in the status register.
Unlocking occurs only for the current power session. As long as the PWD is not cleared the
card will be locked automatically on the next power up. The only way to unlock the card is
by clearing the password.
An attempt to unlock an unlocked card will fail and LOCK_UNLOCK_FAILED error bit
will be set in the Status Register.
In case the user forgot the password (the PWD content) it is possible to erase all the card
data content along with the PWD content. This operation is called Forced Erase:
If the ERASE bit is not the only bit in the data field then the LOCK_UNLOCK_FAILED
error bit will be set in the status register and the erase request is rejected. If the command
was accepted then ALL THE CARD CONTENT WILL BE ERASED including the PWD
and PWD_LEN register content and the locked card will get unlocked.
An attempt to force erase on an unlocked card will fail and LOCK_UNLOCK_FAILED
error bit will be set in the status register.
• Unlock Card
• Force Erase
2. Define the block length (CMD16), given by the 8-bit card lock/unlock mode, the 8-
3. Send the card lock/unlock command with the appropriate data block size on the data
1. Select a card (CMD7), if not previously selected already.
2. Define the block length (CMD16), given by the 8-bit card lock/unlock mode, the 8-
3. Send the card lock/unlock command with the appropriate data block size on the data
1. Select a card (CMD7), if not previously selected already.
2. Define the block length (CMD16) to 1 byte (8-bit card lock/unlock command).
bit password size (in bytes), and the number of bytes of the currently used
password.
line including 16-bit CRC. The data block shall indicate the mode LOCK, the
length (PWD_LEN) and the password (PWD) itself. If the PWD content equals to
the sent password then the card will be locked and the card-locked status bit will be
set
LOCK_UNLOCK_FAILED error bit will be set in the status register. Note that it is
possible to set the password and to lock the card in the same sequence. In such case
the host shall perform all the required steps for setting the password (as described
above) including the bit LOCK set while the new password command is sent. If the
password was previously set (PWD_LEN is not ‘0’), then the card will be locked
automatically after power on reset. An attempt to lock a locked card or to lock a
card that does not have a password will fail and the LOCK_UNLOCK_FAILED
error bit will be set in the Status Register.
bit password size (in bytes), and the number of bytes of the currently used
password.
line including 16-bit CRC. The data block shall indicate the mode UNLOCK, the
length (PWD_LEN) and the password (PWD) itself.
Send the card lock/unlock command with the appropriate data block of one byte on
the data line including 16-bit CRC. The data block shall indicate the mode ERASE
(the ERASE bit shall be the only bit set).
in
the
status
register.
4-10
If
MultiMediaCard/RS-MultiMediaCard Product Manual
Chapter 4 – MultiMediaCard Protocol Description
the
password
is
not
correct
04/22/05
then