MD3331-D32-V3Q18 M-Systems Inc., MD3331-D32-V3Q18 Datasheet - Page 22

• Manufacturer Part Number: MD3331-D32-V3Q18
• Description: Mobile Diskonchip Plus 128Mbits 1.8V I/o
• Manufacturer: M-Systems Inc.

4.
4.1
Mobile DiskOnChip Plus enables the user to define two partitions that are protected (in hardware) against any
combination of read or write operations. The two protected areas can be configured as read protected or write-
protected, and are protected by a protection key (i.e. password) defined by the user. Each of the protected areas can
be configured separately and can function separately, providing maximal flexibility for the user.
The size and protection attributes (protection key/read/write/changeable/lock) of the protected partition are defined
in the media formatting stage (DFORMAT utility or the format function in the TrueFFS SDK).
In order to set or remove a read/write protection, the protection key (i.e., password) must be used, as follows:
Mobile DiskOnChip Plus has an additional hardware safety measurement. If the Lock option is enabled (by means
of software) and the LOCK# ball is asserted, the protected partition has an additional hardware lock that prevents
read/write access to the partition, even with the use of the correct protection key. The LOCK# ball must be asserted
during DFORMAT (and later when the partition is defined as changeable) to enable the additional hard-wired safety
lock.
It is possible to set the Lock option for one session only, that is, until the next power-up or reset. This Sticky Lock
feature can be useful when the boot code in the boot partition must be read/write protected. Upon power-up, the boot
code must be unprotected so the CPU can run it directly from Mobile DiskOnChip Plus. At the end of the boot
process, protection can be set until the next power-up or reset.
Setting the Sticky Lock (SLOCK) bit in the Output Control register to 1 has the same effect as asserting the LOCK#
ball. Once set, SLOCK can only be cleared by asserting the RSTIN# input. Like the LOCK# input, the assertion of
this bit prevents the protection key from disabling the protection for a given partition. For more information, see
Section 7.9. The target partition does not have to be mounted before calling a hardware protection routine.
Only one partition can be defined as “changeable”; i.e., its password and attributes are fully configurable at any time
(from read to write, both or none and visa versa). Note that “un-changeable” partition attributes cannot be changed
unless the media is reformatted.
A change of any of the protection attributes causes a reset of the protection mechanism and consequently the
removal of all device protection keys. That is, if the protection attributes of one partition are changed, the other
partition will lose its key-protected read/write protection.
The only way to read or write from a read or write protected partition is to use the insert key call (even DFORMAT
does not remove the protection). This is also true for modifying its attributes (key, read, write and lock enable state).
Read/write protection is disabled in each one of the following events:
For further information on hardware protection, please refer to the TrueFFS Software Development Kit (SDK)
developer guide or application note AP-DOC-057, Protection and Security-Enabling Features in DiskOnChip Plus.
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Hardware Protection
Method of Operation
Insert the protection key to remove read/write protection.
Remove the protection key to set read/write protection.
Power-down
Change of any protection attribute (not necessarily in the same partition)
Write operation to the IPL area
Removal of the protection key.
Data Sheet, Rev. 1.7
Mobile DiskOnChip Plus 16/32MByte 1.8V I/O
95-SR-000-10-8L