Numonyx™ Wireless Flash Memory (W18)
The protection register shares some of the same internal flash resources as the
parameter partition. Therefore, RWW is only allowed between the protection register
and main partitions.
describes the operations allowed in the protection
register, parameter partition, and main partition during RWW and RWE.
Table 29: Simultaneous Operations Allowed with the Protection Register
Protection
Register
Parameter
Partition
Array Data
See
Description
Main
Partitions
Description
While programming or erasing in a main partition, the protection register can
be read from any other partition. Reading the parameter partition data is not
allowed if the protection register is being read from addresses within the
parameter partition.
While programming or erasing in a main partition, read operations are allowed
in the parameter partition. Accessing the protection registers from parameter
partition addresses is not allowed.
While programming or erasing in a main partition, read operations are allowed
in the parameter partition. Accessing the protection registers in a partition that
is
different
from the one being programmed or erased, and also
different
from
the parameter partition, is allowed.
While programming the protection register, reads are only allowed in the other
main partitions. Access to the parameter partition is not allowed. This is
because programming of the protection register can only occur in the
parameter partition, so it will exist in status mode.
While programming or erasing the parameter partition, reads of the protection
registers are not allowed in
any
partition. Reads in other main partitions are
supported.
Read
Write/Erase
See
Description
Read
Write/Erase
Read
Read
Write/Erase
Write
No Access
Allowed
Read
No Access
Allowed
Write/Erase
Read
13.2.1
Reading the Protection Register
Writing the Read Identifier command allows the protection register data to be read 16
bits at a time from addresses shown in
The protection register is read from the Read Identifier command and can be
read in any partition.Writing the Read Array command returns the device to read-array
mode.
13.2.2
Programing the Protection Register
The Protection Program command should be issued only at the parameter (top or
bottom) partition followed by the data to be programmed at the specified location. It
programs the upper 64 bits of the protection register 16 bits at a time.
shows allowable addresses. See also
Issuing a
Protection Program command outside the register’s address space results in a Status
Register error (SR[4]=1).
13.2.3
Locking the Protection Register
PR-LK.0 is programmed to 0 by Numonyx to protect the unique device number. PR-LK.1
can be programmed by the user to lock the user portion (upper 64 bits) of the
protection register (See
This bit is set using
the Protection Program command to program “FFFDh” into PR-LK.
After PR-LK register bits are programmed (locked), the protection register’s stored
values can’t be changed. Protection Program commands written to a locked section
result in a Status Register error (SR[4]=1, SR[5]=1).
November 2007
Order Number: 290701-18
Datasheet
75
NUMONYX [ NUMONYX B.V ]
